|
In vitro activity against Plasmodium falciparum D6
|
Plasmodium falciparum
|
8.3
nM
|
|
Journal : J. Med. Chem.
Title : Bisquinolines. 1. N,N-bis(7-chloroquinolin-4-yl)alkanediamines with potential against chloroquine-resistant malaria.
Year : 1992
Volume : 35
Issue : 11
First Page : 2129
Last Page : 2134
Authors : Vennerstrom JL, Ellis WY, Ager AL, Andersen SL, Gerena L, Milhous WK.
Abstract : On the basis of observations that several bisquinolines such as piperaquine possess notable activity against chloroquine-resistant malaria, 13 N,N-bis-(7-chloroquinolin-4-yl)alkanediamines were synthesized and screened against Plasmodium falciparum in vitro and Plasmodium berghei in vivo. Twelve of the thirteen bisquinolines had a significantly lower resistance index than did chloroquine; the resistance index was apparently unrelated to either in vitro or in vivo activity. Except for two compounds, there was a reasonable correlation between in vitro and in vivo activities. Seven of the thirteen bisquinolines had IC50's of less than 6 nM against both chloroquine-sensitive (D-6) and -resistant (W-2) clones of P. falciparum and were curative against P. berghei at doses of 640 mg/kg. In contrast to chloroquine, these bisquinolines did not show any toxic deaths at curative dose levels. Four bisquinolines, however, caused skin lesions at the site of injection. Maximum activity was seen in bisquinolines with a connecting bridge of two carbon atoms where decreased conformational mobility seemed to increase activity. Bisquinoline 3 (+/-)-trans-N1,N2-bis(7-chloroquinolin-4-yl)cyclohexane-1,2-diamin e was not only the most potent bisquinoline in vitro, but was clearly unique in its in vivo activity--80% and 100% cure rates were achieved at doses of 160 and 320 mg/kg, respectively. In summary, these preliminary results support the premise that bisquinolines may be useful agents against chloroquine-resistant malaria.
|
In vitro activity against Plasmodium falciparum W-2
|
Plasmodium falciparum
|
16.0
nM
|
|
Journal : J. Med. Chem.
Title : Bisquinolines. 1. N,N-bis(7-chloroquinolin-4-yl)alkanediamines with potential against chloroquine-resistant malaria.
Year : 1992
Volume : 35
Issue : 11
First Page : 2129
Last Page : 2134
Authors : Vennerstrom JL, Ellis WY, Ager AL, Andersen SL, Gerena L, Milhous WK.
Abstract : On the basis of observations that several bisquinolines such as piperaquine possess notable activity against chloroquine-resistant malaria, 13 N,N-bis-(7-chloroquinolin-4-yl)alkanediamines were synthesized and screened against Plasmodium falciparum in vitro and Plasmodium berghei in vivo. Twelve of the thirteen bisquinolines had a significantly lower resistance index than did chloroquine; the resistance index was apparently unrelated to either in vitro or in vivo activity. Except for two compounds, there was a reasonable correlation between in vitro and in vivo activities. Seven of the thirteen bisquinolines had IC50's of less than 6 nM against both chloroquine-sensitive (D-6) and -resistant (W-2) clones of P. falciparum and were curative against P. berghei at doses of 640 mg/kg. In contrast to chloroquine, these bisquinolines did not show any toxic deaths at curative dose levels. Four bisquinolines, however, caused skin lesions at the site of injection. Maximum activity was seen in bisquinolines with a connecting bridge of two carbon atoms where decreased conformational mobility seemed to increase activity. Bisquinoline 3 (+/-)-trans-N1,N2-bis(7-chloroquinolin-4-yl)cyclohexane-1,2-diamin e was not only the most potent bisquinoline in vitro, but was clearly unique in its in vivo activity--80% and 100% cure rates were achieved at doses of 160 and 320 mg/kg, respectively. In summary, these preliminary results support the premise that bisquinolines may be useful agents against chloroquine-resistant malaria.
|
Antiparasitic activity against chloroquine-sensitive Plasmodium falciparum by [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
14.6
nM
|
|
Journal : J. Med. Chem.
Title : Antimalarial dual drugs based on potent inhibitors of glutathione reductase from Plasmodium falciparum.
Year : 2008
Volume : 51
Issue : 5
First Page : 1260
Last Page : 1277
Authors : Friebolin W, Jannack B, Wenzel N, Furrer J, Oeser T, Sanchez CP, Lanzer M, Yardley V, Becker K, Davioud-Charvet E.
Abstract : Plasmodium parasites are exposed to higher fluxes of reactive oxygen species and need high activities of intracellular antioxidant systems providing a steady glutathione flux. As a future generation of dual drugs, 18 naphthoquinones and phenols (or their reduced forms) containing three different linkers between the 4-aminoquinoline core and the redox active component were synthesized. Their antimalarial effects have been characterized in parasite assays using chloroquine-sensitive and -resistant strains of Plasmodium, alone or in drug combination, and in the Plasmodium berghei rodent model. In particular, two tertiary amides 34 and 36 showed potent antimalarial activity in the low nanomolar range against CQ-resistant parasites. The ability to compete both for (Fe (III))protoporphyrin and for chloroquine transporter was determined. The data are consistent with the presence of a carrier for uptake of the short chloroquine analogue 2 but not for the potent antimalarial amide 34, suggesting a mode of action distinct from chloroquine mechanism.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum FC27
|
Plasmodium falciparum
|
29.61
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum T996
|
Plasmodium falciparum
|
19.93
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum 3D7
|
Plasmodium falciparum
|
36.9
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum 106/1
|
Plasmodium falciparum
|
22.22
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum K1
|
Plasmodium falciparum
|
49.03
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum RSA11
|
Plasmodium falciparum
|
51.38
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum 7G8-mdr7G8
|
Plasmodium falciparum
|
49.71
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum 34-1/E
|
Plasmodium falciparum
|
16.38
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Effects of piperaquine, chloroquine, and amodiaquine on drug uptake and of these in combination with dihydroartemisinin against drug-sensitive and -resistant Plasmodium falciparum strains.
Year : 2007
Volume : 51
Issue : 6
First Page : 2265
Last Page : 2267
Authors : Fivelman QL, Adagu IS, Warhurst DC.
Abstract : Piperaquine is being developed as a long-acting component in artemisinin combination therapies. It was highly active in vitro and drug interaction studies showed that dihydroartemisinin combinations with piperaquine, chloroquine, and amodiaquine were indifferent tending toward antagonism. Competitive uptake of radiolabeled chloroquine and dihydroartemisinin in combination with other antimalarials was observed.
|
Antiplasmodial activity against chloroquine-sensitive Plasmodium falciparum
|
Plasmodium falciparum
|
35.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Pharmacokinetics and efficacy of piperaquine and chloroquine in Melanesian children with uncomplicated malaria.
Year : 2008
Volume : 52
Issue : 1
First Page : 237
Last Page : 243
Authors : Karunajeewa HA, Ilett KF, Mueller I, Siba P, Law I, Page-Sharp M, Lin E, Lammey J, Batty KT, Davis TM.
Abstract : The disposition of chloroquine (CQ) and the related 4-aminoquinoline, piperaquine (PQ), were compared in Papua New Guinean children with uncomplicated malaria. Twenty-two children were randomized to 3 days of PQ phosphate at 20 mg/kg/day (12 mg of PQ base/kg/day) coformulated with dihydroartemisinin (DHA-PQ), and twenty children were randomized to 3 days of CQ at 10 mg base/kg/day with a single dose of sulfadoxine-pyrimethamine (CQ-SP). After a 42-day intensive sampling protocol, PQ, CQ, and its active metabolite monodesethyl-chloroquine (DECQ) were assayed in plasma by using high-performance liquid chromatography. A two-compartment model with first-order absorption was fitted to the PQ and CQ data. There were no significant differences in age, gender, body weight, or admission parasitemia between the two groups. The PCR-corrected 42-day adequate clinical and parasitological responses were 100% for DHA-PQ and 94% for CQ-SP, but P. falciparum reinfections during follow-up were common (33 and 18%, respectively). For PQ, the median volume of distribution at steady state, allowing for bioavailability (Vss/F), was 431 liters/kg (interquartile range [IQR], 283 to 588 liters/kg), the median clearance (CL/F) was 0.85 liters/h/kg (IQR, 0.67 to 1.06 liters/h/kg), the median distribution half-life (t 1/2 alpha) was 0.12 h (IQR, 0.05 to 0.66 h), and the median elimination half-life (t 1/2 beta) was 413 h (IQR, 318 to 516 h). For CQ, the median Vss/F was 154 liters/kg (IQR, 101 to 210 liters/kg), the median CL/F was 0.80 liters/h/kg (IQR, 0.52 to 0.96 liters/h/kg), the median t 1/2 alpha was 0.43 h (IQR, 0.05 to 1.82 h), and the median t 1/2 beta was 233 h (IQR, 206 to 298 h). The noncompartmentally derived median DECQ t 1/2 beta was 290 h (IQR, 236 to 368 h). Combined molar concentrations of DECQ and CQ were higher than those of PQ during the elimination phase. Although PQ has a longer t 1/2 beta than CQ, its prompt distribution and lack of active metabolite may limit its posttreatment malaria-suppressive properties.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum
|
Plasmodium falciparum
|
40.7
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Pharmacokinetics and efficacy of piperaquine and chloroquine in Melanesian children with uncomplicated malaria.
Year : 2008
Volume : 52
Issue : 1
First Page : 237
Last Page : 243
Authors : Karunajeewa HA, Ilett KF, Mueller I, Siba P, Law I, Page-Sharp M, Lin E, Lammey J, Batty KT, Davis TM.
Abstract : The disposition of chloroquine (CQ) and the related 4-aminoquinoline, piperaquine (PQ), were compared in Papua New Guinean children with uncomplicated malaria. Twenty-two children were randomized to 3 days of PQ phosphate at 20 mg/kg/day (12 mg of PQ base/kg/day) coformulated with dihydroartemisinin (DHA-PQ), and twenty children were randomized to 3 days of CQ at 10 mg base/kg/day with a single dose of sulfadoxine-pyrimethamine (CQ-SP). After a 42-day intensive sampling protocol, PQ, CQ, and its active metabolite monodesethyl-chloroquine (DECQ) were assayed in plasma by using high-performance liquid chromatography. A two-compartment model with first-order absorption was fitted to the PQ and CQ data. There were no significant differences in age, gender, body weight, or admission parasitemia between the two groups. The PCR-corrected 42-day adequate clinical and parasitological responses were 100% for DHA-PQ and 94% for CQ-SP, but P. falciparum reinfections during follow-up were common (33 and 18%, respectively). For PQ, the median volume of distribution at steady state, allowing for bioavailability (Vss/F), was 431 liters/kg (interquartile range [IQR], 283 to 588 liters/kg), the median clearance (CL/F) was 0.85 liters/h/kg (IQR, 0.67 to 1.06 liters/h/kg), the median distribution half-life (t 1/2 alpha) was 0.12 h (IQR, 0.05 to 0.66 h), and the median elimination half-life (t 1/2 beta) was 413 h (IQR, 318 to 516 h). For CQ, the median Vss/F was 154 liters/kg (IQR, 101 to 210 liters/kg), the median CL/F was 0.80 liters/h/kg (IQR, 0.52 to 0.96 liters/h/kg), the median t 1/2 alpha was 0.43 h (IQR, 0.05 to 1.82 h), and the median t 1/2 beta was 233 h (IQR, 206 to 298 h). The noncompartmentally derived median DECQ t 1/2 beta was 290 h (IQR, 236 to 368 h). Combined molar concentrations of DECQ and CQ were higher than those of PQ during the elimination phase. Although PQ has a longer t 1/2 beta than CQ, its prompt distribution and lack of active metabolite may limit its posttreatment malaria-suppressive properties.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum
|
Plasmodium falciparum
|
36.0
nM
|
|
Journal : Eur. J. Med. Chem.
Title : Quinolines and structurally related heterocycles as antimalarials.
Year : 2010
Volume : 45
Issue : 8
First Page : 3245
Last Page : 3264
Authors : Kaur K, Jain M, Reddy RP, Jain R.
Abstract : The quinoline scaffold is prevalent in a variety of pharmacologically active synthetic and natural compounds. The discovery of chloroquine, the most famous drug containing this scaffold resulted in control and eradication of malaria for decades. The other known antimalarial drugs from the quinoline family include: quinine, amodiaquine, piperaquine, primaquine, and mefloquine. The drugs from this group mostly act during the blood stages of the parasite's life cycle but some like primaquine targets the tissue stages. This review provides a comprehensive literature compilation concerning the study of quinolines and also other heterocycles structurally similar to quinoline scaffold in the treatment of malaria. This review covers advances made in the last ten years and it is subdivided into eight sub-headings. It consists of discussion on the biological activities, structure-activity relationship, and potential biochemical pathways of 4-aminoquinolines, 4-anilinoquinolines, 8-aminoquinolines, quinolines from nature, quinolones, isoquinolines and tetrahydroquinolines, ring-modified quinolines, and miscellaneous quinolines.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum
|
Plasmodium falciparum
|
41.0
nM
|
|
Journal : Eur. J. Med. Chem.
Title : Quinolines and structurally related heterocycles as antimalarials.
Year : 2010
Volume : 45
Issue : 8
First Page : 3245
Last Page : 3264
Authors : Kaur K, Jain M, Reddy RP, Jain R.
Abstract : The quinoline scaffold is prevalent in a variety of pharmacologically active synthetic and natural compounds. The discovery of chloroquine, the most famous drug containing this scaffold resulted in control and eradication of malaria for decades. The other known antimalarial drugs from the quinoline family include: quinine, amodiaquine, piperaquine, primaquine, and mefloquine. The drugs from this group mostly act during the blood stages of the parasite's life cycle but some like primaquine targets the tissue stages. This review provides a comprehensive literature compilation concerning the study of quinolines and also other heterocycles structurally similar to quinoline scaffold in the treatment of malaria. This review covers advances made in the last ten years and it is subdivided into eight sub-headings. It consists of discussion on the biological activities, structure-activity relationship, and potential biochemical pathways of 4-aminoquinolines, 4-anilinoquinolines, 8-aminoquinolines, quinolines from nature, quinolones, isoquinolines and tetrahydroquinolines, ring-modified quinolines, and miscellaneous quinolines.
|
Antimicrobial activity against Plasmodium falciparum by ELISA
|
Plasmodium falciparum
|
6.1
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro sensitivities of Plasmodium falciparum to different antimalarial drugs in Uganda.
Year : 2010
Volume : 54
Issue : 3
First Page : 1200
Last Page : 1206
Authors : Nsobya SL, Kiggundu M, Nanyunja S, Joloba M, Greenhouse B, Rosenthal PJ.
Abstract : The control of malaria is challenged by resistance of Plasmodium falciparum to multiple drugs. New combination regimens are now advocated for the treatment of uncomplicated falciparum malaria, but the extent of resistance to newer agents is incompletely understood. We measured the in vitro sensitivity of P. falciparum parasites cultured from children enrolled in a drug efficacy trial in Kampala, Uganda, from 2006 to 2008. Sensitivities were measured by comparing levels of histidine-rich protein-2 in parasites incubated with different concentrations of drugs with those in untreated controls. The cultured parasites exhibited a wide range of sensitivities to chloroquine (CQ); monodesethylamodiaquine (MDAQ), the major active metabolite of amodiaquine; and quinine (QN). Mean 50% inhibitory concentration (IC(50)) results were above standard cutoffs for resistance for CQ and MDAQ. Parasites were generally sensitive to dihydroartemisinin (DHA), lumefantrine (LM), and piperaquine (PQ). For CQ, MDAQ, and QN but not the other drugs, activities against individual strains were highly correlated. We also assessed known resistance-mediating polymorphisms in two putative transporters, pfcrt and pfmdr1. When parasites that were least and most sensitive to each drug were compared, the pfmdr1 86Y mutation was significantly more common in parasites that were most resistant to CQ and MDAQ, and the pfmdr1 D1246Y mutation was significantly more common in parasites that were most resistant to MDAQ and QN. In summary, we demonstrated in parasites from Kampala a range of sensitivities to older drugs; correlation of sensitivities to CQ, MDAQ, and QN; and good activity against nearly all strains for DHA, LM, and PQ.
|
Antimicrobial activity against chloroquine-sensitive Plasmodium falciparum W2 by ELISA
|
Plasmodium falciparum
|
14.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro sensitivities of Plasmodium falciparum to different antimalarial drugs in Uganda.
Year : 2010
Volume : 54
Issue : 3
First Page : 1200
Last Page : 1206
Authors : Nsobya SL, Kiggundu M, Nanyunja S, Joloba M, Greenhouse B, Rosenthal PJ.
Abstract : The control of malaria is challenged by resistance of Plasmodium falciparum to multiple drugs. New combination regimens are now advocated for the treatment of uncomplicated falciparum malaria, but the extent of resistance to newer agents is incompletely understood. We measured the in vitro sensitivity of P. falciparum parasites cultured from children enrolled in a drug efficacy trial in Kampala, Uganda, from 2006 to 2008. Sensitivities were measured by comparing levels of histidine-rich protein-2 in parasites incubated with different concentrations of drugs with those in untreated controls. The cultured parasites exhibited a wide range of sensitivities to chloroquine (CQ); monodesethylamodiaquine (MDAQ), the major active metabolite of amodiaquine; and quinine (QN). Mean 50% inhibitory concentration (IC(50)) results were above standard cutoffs for resistance for CQ and MDAQ. Parasites were generally sensitive to dihydroartemisinin (DHA), lumefantrine (LM), and piperaquine (PQ). For CQ, MDAQ, and QN but not the other drugs, activities against individual strains were highly correlated. We also assessed known resistance-mediating polymorphisms in two putative transporters, pfcrt and pfmdr1. When parasites that were least and most sensitive to each drug were compared, the pfmdr1 86Y mutation was significantly more common in parasites that were most resistant to CQ and MDAQ, and the pfmdr1 D1246Y mutation was significantly more common in parasites that were most resistant to MDAQ and QN. In summary, we demonstrated in parasites from Kampala a range of sensitivities to older drugs; correlation of sensitivities to CQ, MDAQ, and QN; and good activity against nearly all strains for DHA, LM, and PQ.
|
Antimicrobial activity against chloroquine-sensitive Plasmodium falciparum D6 by ELISA
|
Plasmodium falciparum
|
6.26
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro sensitivities of Plasmodium falciparum to different antimalarial drugs in Uganda.
Year : 2010
Volume : 54
Issue : 3
First Page : 1200
Last Page : 1206
Authors : Nsobya SL, Kiggundu M, Nanyunja S, Joloba M, Greenhouse B, Rosenthal PJ.
Abstract : The control of malaria is challenged by resistance of Plasmodium falciparum to multiple drugs. New combination regimens are now advocated for the treatment of uncomplicated falciparum malaria, but the extent of resistance to newer agents is incompletely understood. We measured the in vitro sensitivity of P. falciparum parasites cultured from children enrolled in a drug efficacy trial in Kampala, Uganda, from 2006 to 2008. Sensitivities were measured by comparing levels of histidine-rich protein-2 in parasites incubated with different concentrations of drugs with those in untreated controls. The cultured parasites exhibited a wide range of sensitivities to chloroquine (CQ); monodesethylamodiaquine (MDAQ), the major active metabolite of amodiaquine; and quinine (QN). Mean 50% inhibitory concentration (IC(50)) results were above standard cutoffs for resistance for CQ and MDAQ. Parasites were generally sensitive to dihydroartemisinin (DHA), lumefantrine (LM), and piperaquine (PQ). For CQ, MDAQ, and QN but not the other drugs, activities against individual strains were highly correlated. We also assessed known resistance-mediating polymorphisms in two putative transporters, pfcrt and pfmdr1. When parasites that were least and most sensitive to each drug were compared, the pfmdr1 86Y mutation was significantly more common in parasites that were most resistant to CQ and MDAQ, and the pfmdr1 D1246Y mutation was significantly more common in parasites that were most resistant to MDAQ and QN. In summary, we demonstrated in parasites from Kampala a range of sensitivities to older drugs; correlation of sensitivities to CQ, MDAQ, and QN; and good activity against nearly all strains for DHA, LM, and PQ.
|
Antimicrobial activity against chloroquine-resistant Plasmodium falciparum HB3 by ELISA
|
Plasmodium falciparum HB3
|
10.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro sensitivities of Plasmodium falciparum to different antimalarial drugs in Uganda.
Year : 2010
Volume : 54
Issue : 3
First Page : 1200
Last Page : 1206
Authors : Nsobya SL, Kiggundu M, Nanyunja S, Joloba M, Greenhouse B, Rosenthal PJ.
Abstract : The control of malaria is challenged by resistance of Plasmodium falciparum to multiple drugs. New combination regimens are now advocated for the treatment of uncomplicated falciparum malaria, but the extent of resistance to newer agents is incompletely understood. We measured the in vitro sensitivity of P. falciparum parasites cultured from children enrolled in a drug efficacy trial in Kampala, Uganda, from 2006 to 2008. Sensitivities were measured by comparing levels of histidine-rich protein-2 in parasites incubated with different concentrations of drugs with those in untreated controls. The cultured parasites exhibited a wide range of sensitivities to chloroquine (CQ); monodesethylamodiaquine (MDAQ), the major active metabolite of amodiaquine; and quinine (QN). Mean 50% inhibitory concentration (IC(50)) results were above standard cutoffs for resistance for CQ and MDAQ. Parasites were generally sensitive to dihydroartemisinin (DHA), lumefantrine (LM), and piperaquine (PQ). For CQ, MDAQ, and QN but not the other drugs, activities against individual strains were highly correlated. We also assessed known resistance-mediating polymorphisms in two putative transporters, pfcrt and pfmdr1. When parasites that were least and most sensitive to each drug were compared, the pfmdr1 86Y mutation was significantly more common in parasites that were most resistant to CQ and MDAQ, and the pfmdr1 D1246Y mutation was significantly more common in parasites that were most resistant to MDAQ and QN. In summary, we demonstrated in parasites from Kampala a range of sensitivities to older drugs; correlation of sensitivities to CQ, MDAQ, and QN; and good activity against nearly all strains for DHA, LM, and PQ.
|
Antimicrobial activity against chloroquine-resistant Plasmodium falciparum K1 by ELISA
|
Plasmodium falciparum K1
|
12.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro sensitivities of Plasmodium falciparum to different antimalarial drugs in Uganda.
Year : 2010
Volume : 54
Issue : 3
First Page : 1200
Last Page : 1206
Authors : Nsobya SL, Kiggundu M, Nanyunja S, Joloba M, Greenhouse B, Rosenthal PJ.
Abstract : The control of malaria is challenged by resistance of Plasmodium falciparum to multiple drugs. New combination regimens are now advocated for the treatment of uncomplicated falciparum malaria, but the extent of resistance to newer agents is incompletely understood. We measured the in vitro sensitivity of P. falciparum parasites cultured from children enrolled in a drug efficacy trial in Kampala, Uganda, from 2006 to 2008. Sensitivities were measured by comparing levels of histidine-rich protein-2 in parasites incubated with different concentrations of drugs with those in untreated controls. The cultured parasites exhibited a wide range of sensitivities to chloroquine (CQ); monodesethylamodiaquine (MDAQ), the major active metabolite of amodiaquine; and quinine (QN). Mean 50% inhibitory concentration (IC(50)) results were above standard cutoffs for resistance for CQ and MDAQ. Parasites were generally sensitive to dihydroartemisinin (DHA), lumefantrine (LM), and piperaquine (PQ). For CQ, MDAQ, and QN but not the other drugs, activities against individual strains were highly correlated. We also assessed known resistance-mediating polymorphisms in two putative transporters, pfcrt and pfmdr1. When parasites that were least and most sensitive to each drug were compared, the pfmdr1 86Y mutation was significantly more common in parasites that were most resistant to CQ and MDAQ, and the pfmdr1 D1246Y mutation was significantly more common in parasites that were most resistant to MDAQ and QN. In summary, we demonstrated in parasites from Kampala a range of sensitivities to older drugs; correlation of sensitivities to CQ, MDAQ, and QN; and good activity against nearly all strains for DHA, LM, and PQ.
|
Antimicrobial activity against Plasmodium falciparum harboring mdr1 N86Y/D1246Y/Y184F mutant gene by ELISA
|
Plasmodium falciparum
|
1.6
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro sensitivities of Plasmodium falciparum to different antimalarial drugs in Uganda.
Year : 2010
Volume : 54
Issue : 3
First Page : 1200
Last Page : 1206
Authors : Nsobya SL, Kiggundu M, Nanyunja S, Joloba M, Greenhouse B, Rosenthal PJ.
Abstract : The control of malaria is challenged by resistance of Plasmodium falciparum to multiple drugs. New combination regimens are now advocated for the treatment of uncomplicated falciparum malaria, but the extent of resistance to newer agents is incompletely understood. We measured the in vitro sensitivity of P. falciparum parasites cultured from children enrolled in a drug efficacy trial in Kampala, Uganda, from 2006 to 2008. Sensitivities were measured by comparing levels of histidine-rich protein-2 in parasites incubated with different concentrations of drugs with those in untreated controls. The cultured parasites exhibited a wide range of sensitivities to chloroquine (CQ); monodesethylamodiaquine (MDAQ), the major active metabolite of amodiaquine; and quinine (QN). Mean 50% inhibitory concentration (IC(50)) results were above standard cutoffs for resistance for CQ and MDAQ. Parasites were generally sensitive to dihydroartemisinin (DHA), lumefantrine (LM), and piperaquine (PQ). For CQ, MDAQ, and QN but not the other drugs, activities against individual strains were highly correlated. We also assessed known resistance-mediating polymorphisms in two putative transporters, pfcrt and pfmdr1. When parasites that were least and most sensitive to each drug were compared, the pfmdr1 86Y mutation was significantly more common in parasites that were most resistant to CQ and MDAQ, and the pfmdr1 D1246Y mutation was significantly more common in parasites that were most resistant to MDAQ and QN. In summary, we demonstrated in parasites from Kampala a range of sensitivities to older drugs; correlation of sensitivities to CQ, MDAQ, and QN; and good activity against nearly all strains for DHA, LM, and PQ.
|
Antimicrobial activity against Plasmodium vivax trophozoites measured after 30 hrs by microscopy
|
Plasmodium vivax
|
29.1
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Determinants of in vitro drug susceptibility testing of Plasmodium vivax.
Year : 2008
Volume : 52
Issue : 3
First Page : 1040
Last Page : 1045
Authors : Russell B, Chalfein F, Prasetyorini B, Kenangalem E, Piera K, Suwanarusk R, Brockman A, Prayoga P, Sugiarto P, Cheng Q, Tjitra E, Anstey NM, Price RN.
Abstract : In Papua, Indonesia, the antimalarial susceptibility of Plasmodium vivax (n = 216) and P. falciparum (n = 277) was assessed using a modified schizont maturation assay for chloroquine, amodiaquine, artesunate, lumefantrine, mefloquine, and piperaquine. The most effective antimalarial against P. vivax and P. falciparum was artesunate, with geometric mean 50% inhibitory concentrations (IC50s) (95% confidence intervals [CI]) of 1.31 nM (1.07 to 1.59) and 0.64 nM (0.53 to 0.79), respectively. In contrast, the geometric mean chloroquine IC50 for P. vivax was 295 nM (227 to 384) compared to only 47.4 nM (42.2 to 53.3) for P. falciparum. Two factors were found to significantly influence the in vitro drug response of P. vivax: the initial stage of the parasite and the duration of the assay. Isolates of P. vivax initially at the trophozoite stage had significantly higher chloroquine IC50s (478 nM [95% CI, 316 to 722]) than those initially at the ring stage (84.7 nM [95% CI, 45.7 to 157]; P < 0.001). Synchronous isolates of P. vivax and P. falciparum which reached the target of 40% schizonts in the control wells within 30 h had significantly higher geometric mean chloroquine IC50s (435 nM [95% CI, 169 to 1,118] and 55.9 nM [95% CI, 48 to 64.9], respectively) than isolates that took more than 30 h (39.9 nM [14.6 to 110.4] and 36.9 nM [31.2 to 43.7]; P < 0.005). The results demonstrate the marked stage-specific activity of chloroquine with P. vivax and suggest that susceptibility to chloroquine may be associated with variable growth rates. These findings have important implications for the phenotypic and downstream genetic characterization of P. vivax.
|
Antimicrobial activity against Plasmodium vivax at the ring stage measured after 30 hrs by microscopy
|
Plasmodium vivax
|
14.6
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Determinants of in vitro drug susceptibility testing of Plasmodium vivax.
Year : 2008
Volume : 52
Issue : 3
First Page : 1040
Last Page : 1045
Authors : Russell B, Chalfein F, Prasetyorini B, Kenangalem E, Piera K, Suwanarusk R, Brockman A, Prayoga P, Sugiarto P, Cheng Q, Tjitra E, Anstey NM, Price RN.
Abstract : In Papua, Indonesia, the antimalarial susceptibility of Plasmodium vivax (n = 216) and P. falciparum (n = 277) was assessed using a modified schizont maturation assay for chloroquine, amodiaquine, artesunate, lumefantrine, mefloquine, and piperaquine. The most effective antimalarial against P. vivax and P. falciparum was artesunate, with geometric mean 50% inhibitory concentrations (IC50s) (95% confidence intervals [CI]) of 1.31 nM (1.07 to 1.59) and 0.64 nM (0.53 to 0.79), respectively. In contrast, the geometric mean chloroquine IC50 for P. vivax was 295 nM (227 to 384) compared to only 47.4 nM (42.2 to 53.3) for P. falciparum. Two factors were found to significantly influence the in vitro drug response of P. vivax: the initial stage of the parasite and the duration of the assay. Isolates of P. vivax initially at the trophozoite stage had significantly higher chloroquine IC50s (478 nM [95% CI, 316 to 722]) than those initially at the ring stage (84.7 nM [95% CI, 45.7 to 157]; P < 0.001). Synchronous isolates of P. vivax and P. falciparum which reached the target of 40% schizonts in the control wells within 30 h had significantly higher geometric mean chloroquine IC50s (435 nM [95% CI, 169 to 1,118] and 55.9 nM [95% CI, 48 to 64.9], respectively) than isolates that took more than 30 h (39.9 nM [14.6 to 110.4] and 36.9 nM [31.2 to 43.7]; P < 0.005). The results demonstrate the marked stage-specific activity of chloroquine with P. vivax and suggest that susceptibility to chloroquine may be associated with variable growth rates. These findings have important implications for the phenotypic and downstream genetic characterization of P. vivax.
|
Antimicrobial activity against Plasmodium vivax trophozoites measured within 30 hrs by microscopy
|
Plasmodium vivax
|
22.9
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Determinants of in vitro drug susceptibility testing of Plasmodium vivax.
Year : 2008
Volume : 52
Issue : 3
First Page : 1040
Last Page : 1045
Authors : Russell B, Chalfein F, Prasetyorini B, Kenangalem E, Piera K, Suwanarusk R, Brockman A, Prayoga P, Sugiarto P, Cheng Q, Tjitra E, Anstey NM, Price RN.
Abstract : In Papua, Indonesia, the antimalarial susceptibility of Plasmodium vivax (n = 216) and P. falciparum (n = 277) was assessed using a modified schizont maturation assay for chloroquine, amodiaquine, artesunate, lumefantrine, mefloquine, and piperaquine. The most effective antimalarial against P. vivax and P. falciparum was artesunate, with geometric mean 50% inhibitory concentrations (IC50s) (95% confidence intervals [CI]) of 1.31 nM (1.07 to 1.59) and 0.64 nM (0.53 to 0.79), respectively. In contrast, the geometric mean chloroquine IC50 for P. vivax was 295 nM (227 to 384) compared to only 47.4 nM (42.2 to 53.3) for P. falciparum. Two factors were found to significantly influence the in vitro drug response of P. vivax: the initial stage of the parasite and the duration of the assay. Isolates of P. vivax initially at the trophozoite stage had significantly higher chloroquine IC50s (478 nM [95% CI, 316 to 722]) than those initially at the ring stage (84.7 nM [95% CI, 45.7 to 157]; P < 0.001). Synchronous isolates of P. vivax and P. falciparum which reached the target of 40% schizonts in the control wells within 30 h had significantly higher geometric mean chloroquine IC50s (435 nM [95% CI, 169 to 1,118] and 55.9 nM [95% CI, 48 to 64.9], respectively) than isolates that took more than 30 h (39.9 nM [14.6 to 110.4] and 36.9 nM [31.2 to 43.7]; P < 0.005). The results demonstrate the marked stage-specific activity of chloroquine with P. vivax and suggest that susceptibility to chloroquine may be associated with variable growth rates. These findings have important implications for the phenotypic and downstream genetic characterization of P. vivax.
|
Antimicrobial activity against Plasmodium vivax at the ring stage measured within 30 hrs by microscopy
|
Plasmodium vivax
|
31.2
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Determinants of in vitro drug susceptibility testing of Plasmodium vivax.
Year : 2008
Volume : 52
Issue : 3
First Page : 1040
Last Page : 1045
Authors : Russell B, Chalfein F, Prasetyorini B, Kenangalem E, Piera K, Suwanarusk R, Brockman A, Prayoga P, Sugiarto P, Cheng Q, Tjitra E, Anstey NM, Price RN.
Abstract : In Papua, Indonesia, the antimalarial susceptibility of Plasmodium vivax (n = 216) and P. falciparum (n = 277) was assessed using a modified schizont maturation assay for chloroquine, amodiaquine, artesunate, lumefantrine, mefloquine, and piperaquine. The most effective antimalarial against P. vivax and P. falciparum was artesunate, with geometric mean 50% inhibitory concentrations (IC50s) (95% confidence intervals [CI]) of 1.31 nM (1.07 to 1.59) and 0.64 nM (0.53 to 0.79), respectively. In contrast, the geometric mean chloroquine IC50 for P. vivax was 295 nM (227 to 384) compared to only 47.4 nM (42.2 to 53.3) for P. falciparum. Two factors were found to significantly influence the in vitro drug response of P. vivax: the initial stage of the parasite and the duration of the assay. Isolates of P. vivax initially at the trophozoite stage had significantly higher chloroquine IC50s (478 nM [95% CI, 316 to 722]) than those initially at the ring stage (84.7 nM [95% CI, 45.7 to 157]; P < 0.001). Synchronous isolates of P. vivax and P. falciparum which reached the target of 40% schizonts in the control wells within 30 h had significantly higher geometric mean chloroquine IC50s (435 nM [95% CI, 169 to 1,118] and 55.9 nM [95% CI, 48 to 64.9], respectively) than isolates that took more than 30 h (39.9 nM [14.6 to 110.4] and 36.9 nM [31.2 to 43.7]; P < 0.005). The results demonstrate the marked stage-specific activity of chloroquine with P. vivax and suggest that susceptibility to chloroquine may be associated with variable growth rates. These findings have important implications for the phenotypic and downstream genetic characterization of P. vivax.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum TM6 infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
15.8
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum 7G8 infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum 7G8
|
11.2
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-sensitive Plasmodium falciparum 3D7 infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
3.4
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-sensitive Plasmodium falciparum C2 infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
3.9
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum C3 harboring Dd2 pfcrt allele infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
11.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum C6harboring 7G8 pfcrt allele infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
6.6
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-sensitive Plasmodium falciparum D10 infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum D10
|
8.1
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-sensitive Plasmodium falciparum D10 harboring 7G8 pfcrt allele infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum D10
|
10.4
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum 7G8 harboring parental pfcrt allele infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum 7G8
|
9.1
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum 7G8 harboring D10 pfcrt allele infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum 7G8
|
12.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antimalarial activity against Plasmodium falciparum
|
Plasmodium falciparum
|
56.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activities of quinine and other antimalarials and pfnhe polymorphisms in Plasmodium isolates from Kenya.
Year : 2010
Volume : 54
Issue : 8
First Page : 3302
Last Page : 3307
Authors : Okombo J, Kiara SM, Rono J, Mwai L, Pole L, Ohuma E, Borrmann S, Ochola LI, Nzila A.
Abstract : Resistance to the amino alcohol quinine has been associated with polymorphisms in pfnhe, a sodium hydrogen exchanger. We investigated the role of this gene in quinine resistance in vitro in isolates from Kenya. We analyzed pfnhe whole-gene polymorphisms, using capillary sequencing, and pfcrt at codon 76 (pfcrt-76) and pfmdr1 at codon 86 (pfmdr1-86), using PCR-enzyme restriction methodology, in 29 isolates from Kilifi, Kenya, for association with the in vitro activities of quinine and 2 amino alcohols, mefloquine and halofantrine. In vitro activity was assessed as the drug concentration that inhibits 50% of parasite growth (IC50). The median IC50s of quinine, halofantrine, and mefloquine were 92, 22, and 18 nM, respectively. The presence of 2 DNNND repeats in microsatellite ms4760 of pfnhe was associated with reduced susceptibility to quinine (60 versus 227 nM for 1 and 2 repeats, respectively; P<0.05), while 3 repeats were associated with restoration of susceptibility. The decrease in susceptibility conferred by the 2 DNNND repeats was more pronounced in parasites harboring the pfmdr1-86 mutation. No association was found between susceptibility to quinine and the pfcrt-76 mutation or between susceptibility to mefloquine or halofantrine and the pfnhe gene and the pfcrt-76 and pfmdr1-86 mutations. Using previously published data on the in vitro activities of chloroquine, lumefantrine, piperaquine, and dihydroartemisinin, we investigated the association of their activities with pfnhe polymorphism. With the exception of a modulation of the activity of lumefantrine by a mutation at position 1437, pfnhe did not modulate their activities. Two DNNND repeats combined with the pfmdr1-86 mutation could be used as an indicator of reduced susceptibility to quinine.
|
Antiplasmodial activity against chloroquine-resistant Plasmodium falciparum K1 infected in erythrocytes assessed as [3H]hypoxanthine incorporation
|
Plasmodium falciparum K1
|
13.4
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Role of known molecular markers of resistance in the antimalarial potency of piperaquine and dihydroartemisinin in vitro.
Year : 2009
Volume : 53
Issue : 4
First Page : 1362
Last Page : 1366
Authors : Muangnoicharoen S, Johnson DJ, Looareesuwan S, Krudsood S, Ward SA.
Abstract : Using a range of laboratory-adapted and genetically modified Plasmodium falciparum parasite isolates, we investigated the interaction between dihydroartemisinin and piperaquine (PIP), the individual components of an artemisinin combination therapy currently under development, in addition to the role of known drug resistance genes in parasite susceptibility in vitro. All but one parasite line investigated displayed an interaction of dihydroartemisinin and PIP that was antagonistic, although the degree of antagonism was isolate dependent. In terms of resistance markers, the pfcrt haplotypes CVIET and SVMNT were positively associated with reduced sensitivity to PIP, with parasites carrying the South American CQR (SVMNT) allele being generally less sensitive than CVIET parasites. Parasites carrying the CQS (CVMNK) allele displayed a further increase in PIP sensitivity compared with CVIET and SVMNT parasites. Our data indicate that PIP sensitivity was not affected by pfmdr1 sequence status, despite positive correlations between the structurally related compound amodiaquine and pfmdr1 mutations in other studies. In contrast, neither the pfcrt nor pfmdr1 sequence status had any significant impact on susceptibility to dihydroartemisinin.
|
Antimalarial activity against chloroquine-resistant Plasmodium vivax by Giemsa staining
|
Plasmodium vivax
|
17.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vivo and in vitro efficacy of amodiaquine monotherapy for treatment of infection by chloroquine-resistant Plasmodium vivax.
Year : 2009
Volume : 53
Issue : 3
First Page : 1094
Last Page : 1099
Authors : Hasugian AR, Tjitra E, Ratcliff A, Siswantoro H, Kenangalem E, Wuwung RM, Purba HL, Piera KA, Chalfien F, Marfurt J, Penttinen PM, Russell B, Anstey NM, Price RN.
Abstract : Amodiaquine retains efficacy against infection by chloroquine-resistant Plasmodium falciparum; however, little information is available on its efficacy against infection by chloroquine-resistant Plasmodium vivax. Patients presenting to a rural clinic with a pure P. vivax infection that recurred after recent antimalarial treatment were retreated, this time with amodiaquine monotherapy, and the risk of further recurrence within 4 weeks was assessed. Of the 87 patients with pure P. vivax infection, 15 patients did not complete a full course of treatment, 4 of whom were intolerant to treatment. In the 72 patients completing treatment, 91% (63 of 69) had cleared their parasitemia within 48 h with no early treatment failure. Follow-up to day 28 or recurrent parasitemia was achieved for 56 patients (78%). The cumulative incidence of treatment failure by day 28 was 22.8% (95% confidence interval, 7.3 to 38%). The in vitro sensitivity profile was determined for a separate set of isolates from outpatients with pure P. vivax infection. The median 50% inhibitory concentration of amodiaquine was 11.3 nM (range, 0.37 to 95.8) and was correlated significantly with that of chloroquine (Spearman rank correlation coefficient, 0.602; P < 0.001). Although amodiaquine results in a rapid clinical response, the risk of recurrence by day 28 is unacceptably high, reducing its suitability as an alternative treatment of infection by chloroquine-resistant P. vivax in this region.
|
Antiplasmodial activity against Plasmodium falciparum K1 assessed as inhibition of [3H]hypoxanthine incorporation by beta counting
|
Plasmodium falciparum K1
|
82.06
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Pharmacokinetics and ex vivo pharmacodynamic antimalarial activity of dihydroartemisinin-piperaquine in patients with uncomplicated falciparum malaria in Vietnam.
Year : 2009
Volume : 53
Issue : 8
First Page : 3534
Last Page : 3537
Authors : Nguyen DV, Nguyen QP, Nguyen ND, Le TT, Nguyen TD, Dinh DN, Nguyen TX, Bui D, Chavchich M, Edstein MD.
Abstract : Compared to healthy subjects, malaria patients show a reduction in the mean oral clearance (1.19 versus 5.87 liters/h/kg of body weight) and apparent volume of distribution (1.47 versus 8.02 liters/kg) of dihydroartemisinin in Vietnamese patients following treatment with dihydroartemisinin-piperaquine (Artekin) for uncomplicated Plasmodium falciparum. Dihydroartemisinin is responsible for most of the ex vivo antimalarial activity of dihydroartemisinin-piperaquine.
|
Antiplasmodial activity against multidrug-resistant Plasmodium falciparum VS/1 by [3H]hypoxanthine incorporation assay
|
Plasmodium falciparum VS/1
|
88.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro chemosensitization of Plasmodium falciparum to antimalarials by verapamil and probenecid.
Year : 2009
Volume : 53
Issue : 7
First Page : 3131
Last Page : 3134
Authors : Masseno V, Muriithi S, Nzila A.
Abstract : We tested the effect of probenecid and verapamil in chemosensitizing Plasmodium falciparum to 14 antimalarials using the multidrug-resistant strain V1S and the drug-sensitive 3D7. Verapamil chemosensitizes V1S to quinine and chloroquine. Interestingly, probenecid profoundly chemosensitizes V1S to piperaquine. Thus, probenecid could be used to increase piperaquine efficacy in vivo.
|
Antimalarial activity against Plasmodium falciparum IMT 9881 harboring Ppcrt I371R mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
56.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 10336 harboring Pfcrt Q271E mutant gene and Ppcrt I371R mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
74.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 10354 harboring Ppcrt M74I, N75E, K76T, A220S mutant gene, Pmdr1 D1246Y mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
29.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 10500 harboring Pfcrt Q271E mutant gene and Ppcrt I371R mutant gene and Pfnhe-1 ms4760 microsatellite mutant assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
81.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 16332 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E mutant gene, Pmdr1 N86Y mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
48.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT K14 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S mutant gene, Pmdr1 Y184F, S1034C, N1042D, D1246Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
61.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT K2 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S mutant gene, Pmdr1 S1034C, N1042D mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
84.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT K4 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S mutant gene, Pmdr1 S1034C, N1042D mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
64.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT L1 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
47.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT Vol harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
37.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum 3D7 harboring Ppcrt I371R mutant gene and Pfnhe-1 ms4760 microsatellite mutant assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
58.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antiplasmodial activity against multidrug-resistant Plasmodium falciparum VS/1 after 18 hrs by [3H]hypoxanthine incorporation assay
|
Plasmodium falciparum VS/1
|
42.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activities of piperaquine, lumefantrine, and dihydroartemisinin in Kenyan Plasmodium falciparum isolates and polymorphisms in pfcrt and pfmdr1.
Year : 2009
Volume : 53
Issue : 12
First Page : 5069
Last Page : 5073
Authors : Mwai L, Kiara SM, Abdirahman A, Pole L, Rippert A, Diriye A, Bull P, Marsh K, Borrmann S, Nzila A.
Abstract : We have analyzed the in vitro chemosensitivity profiles of 115 Kenyan isolates for chloroquine (CQ), piperaquine, lumefantrine (LM), and dihydroartemisinin in association with polymorphisms in pfcrt at codon 76 and pfmdr1 at codon 86, as well as with variations of the copy number of pfmdr1. The median drug concentrations that inhibit 50% of parasite growth (IC(50)s) were 41 nM (interquartile range [IQR], 18 to 73 nM), 50 nM (IQR, 29 to 96 nM), 32 nM (IQR, 17 to 46 nM), and 2 nM (IQR, 1 to 3 nM) for CQ, LM, piperaquine, and dihydroartemisinin, respectively. The activity of CQ correlated inversely with that of LM (r(2) = -0.26; P = 0.02). Interestingly, parasites for which LM IC(50)s were higher were wild type for pfcrt-76 and pfmdr1-86. All isolates had one pfmdr1 copy. Thus, the decrease in LM activity is associated with the selection of wild-type pfcrt-76 and pfmdr1-86 parasites, a feature that accounts for the inverse relationship between CQ and LM. Therefore, the use of LM-artemether is likely to lead to the selection of more CQ-susceptible parasites.
|
Antiplasmodial activity against multidrug-sensitive Plasmodium falciparum 3D7 after 18 hrs by [3H]hypoxanthine incorporation assay
|
Plasmodium falciparum
|
27.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activities of piperaquine, lumefantrine, and dihydroartemisinin in Kenyan Plasmodium falciparum isolates and polymorphisms in pfcrt and pfmdr1.
Year : 2009
Volume : 53
Issue : 12
First Page : 5069
Last Page : 5073
Authors : Mwai L, Kiara SM, Abdirahman A, Pole L, Rippert A, Diriye A, Bull P, Marsh K, Borrmann S, Nzila A.
Abstract : We have analyzed the in vitro chemosensitivity profiles of 115 Kenyan isolates for chloroquine (CQ), piperaquine, lumefantrine (LM), and dihydroartemisinin in association with polymorphisms in pfcrt at codon 76 and pfmdr1 at codon 86, as well as with variations of the copy number of pfmdr1. The median drug concentrations that inhibit 50% of parasite growth (IC(50)s) were 41 nM (interquartile range [IQR], 18 to 73 nM), 50 nM (IQR, 29 to 96 nM), 32 nM (IQR, 17 to 46 nM), and 2 nM (IQR, 1 to 3 nM) for CQ, LM, piperaquine, and dihydroartemisinin, respectively. The activity of CQ correlated inversely with that of LM (r(2) = -0.26; P = 0.02). Interestingly, parasites for which LM IC(50)s were higher were wild type for pfcrt-76 and pfmdr1-86. All isolates had one pfmdr1 copy. Thus, the decrease in LM activity is associated with the selection of wild-type pfcrt-76 and pfmdr1-86 parasites, a feature that accounts for the inverse relationship between CQ and LM. Therefore, the use of LM-artemether is likely to lead to the selection of more CQ-susceptible parasites.
|
Antiplasmodial activity against Plasmodium falciparum clinical isolate after 18 hrs by [3H]hypoxanthine incorporation assay
|
Plasmodium falciparum
|
32.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activities of piperaquine, lumefantrine, and dihydroartemisinin in Kenyan Plasmodium falciparum isolates and polymorphisms in pfcrt and pfmdr1.
Year : 2009
Volume : 53
Issue : 12
First Page : 5069
Last Page : 5073
Authors : Mwai L, Kiara SM, Abdirahman A, Pole L, Rippert A, Diriye A, Bull P, Marsh K, Borrmann S, Nzila A.
Abstract : We have analyzed the in vitro chemosensitivity profiles of 115 Kenyan isolates for chloroquine (CQ), piperaquine, lumefantrine (LM), and dihydroartemisinin in association with polymorphisms in pfcrt at codon 76 and pfmdr1 at codon 86, as well as with variations of the copy number of pfmdr1. The median drug concentrations that inhibit 50% of parasite growth (IC(50)s) were 41 nM (interquartile range [IQR], 18 to 73 nM), 50 nM (IQR, 29 to 96 nM), 32 nM (IQR, 17 to 46 nM), and 2 nM (IQR, 1 to 3 nM) for CQ, LM, piperaquine, and dihydroartemisinin, respectively. The activity of CQ correlated inversely with that of LM (r(2) = -0.26; P = 0.02). Interestingly, parasites for which LM IC(50)s were higher were wild type for pfcrt-76 and pfmdr1-86. All isolates had one pfmdr1 copy. Thus, the decrease in LM activity is associated with the selection of wild-type pfcrt-76 and pfmdr1-86 parasites, a feature that accounts for the inverse relationship between CQ and LM. Therefore, the use of LM-artemether is likely to lead to the selection of more CQ-susceptible parasites.
|
Antiplasmodial activity against Plasmodium falciparum harboring wild type pfcrt-76 gene after 18 hrs by [3H]hypoxanthine incorporation assay
|
Plasmodium falciparum
|
35.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activities of piperaquine, lumefantrine, and dihydroartemisinin in Kenyan Plasmodium falciparum isolates and polymorphisms in pfcrt and pfmdr1.
Year : 2009
Volume : 53
Issue : 12
First Page : 5069
Last Page : 5073
Authors : Mwai L, Kiara SM, Abdirahman A, Pole L, Rippert A, Diriye A, Bull P, Marsh K, Borrmann S, Nzila A.
Abstract : We have analyzed the in vitro chemosensitivity profiles of 115 Kenyan isolates for chloroquine (CQ), piperaquine, lumefantrine (LM), and dihydroartemisinin in association with polymorphisms in pfcrt at codon 76 and pfmdr1 at codon 86, as well as with variations of the copy number of pfmdr1. The median drug concentrations that inhibit 50% of parasite growth (IC(50)s) were 41 nM (interquartile range [IQR], 18 to 73 nM), 50 nM (IQR, 29 to 96 nM), 32 nM (IQR, 17 to 46 nM), and 2 nM (IQR, 1 to 3 nM) for CQ, LM, piperaquine, and dihydroartemisinin, respectively. The activity of CQ correlated inversely with that of LM (r(2) = -0.26; P = 0.02). Interestingly, parasites for which LM IC(50)s were higher were wild type for pfcrt-76 and pfmdr1-86. All isolates had one pfmdr1 copy. Thus, the decrease in LM activity is associated with the selection of wild-type pfcrt-76 and pfmdr1-86 parasites, a feature that accounts for the inverse relationship between CQ and LM. Therefore, the use of LM-artemether is likely to lead to the selection of more CQ-susceptible parasites.
|
Antiplasmodial activity against Plasmodium falciparum harboring mutant pfcrt-76 gene after 18 hrs by [3H]hypoxanthine incorporation assay
|
Plasmodium falciparum
|
38.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activities of piperaquine, lumefantrine, and dihydroartemisinin in Kenyan Plasmodium falciparum isolates and polymorphisms in pfcrt and pfmdr1.
Year : 2009
Volume : 53
Issue : 12
First Page : 5069
Last Page : 5073
Authors : Mwai L, Kiara SM, Abdirahman A, Pole L, Rippert A, Diriye A, Bull P, Marsh K, Borrmann S, Nzila A.
Abstract : We have analyzed the in vitro chemosensitivity profiles of 115 Kenyan isolates for chloroquine (CQ), piperaquine, lumefantrine (LM), and dihydroartemisinin in association with polymorphisms in pfcrt at codon 76 and pfmdr1 at codon 86, as well as with variations of the copy number of pfmdr1. The median drug concentrations that inhibit 50% of parasite growth (IC(50)s) were 41 nM (interquartile range [IQR], 18 to 73 nM), 50 nM (IQR, 29 to 96 nM), 32 nM (IQR, 17 to 46 nM), and 2 nM (IQR, 1 to 3 nM) for CQ, LM, piperaquine, and dihydroartemisinin, respectively. The activity of CQ correlated inversely with that of LM (r(2) = -0.26; P = 0.02). Interestingly, parasites for which LM IC(50)s were higher were wild type for pfcrt-76 and pfmdr1-86. All isolates had one pfmdr1 copy. Thus, the decrease in LM activity is associated with the selection of wild-type pfcrt-76 and pfmdr1-86 parasites, a feature that accounts for the inverse relationship between CQ and LM. Therefore, the use of LM-artemether is likely to lead to the selection of more CQ-susceptible parasites.
|
Antimalarial activity against Plasmodium falciparum 3D7 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
58.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum W2 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
52.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum D6 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
58.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum FCM29 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
98.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum FCR3 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
53.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum PA assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
80.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum HB3 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum HB3
|
55.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum 106/1 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
69.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT Bres assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
46.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT Guy assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
63.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT A4 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
75.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 31 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
48.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 8425 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
44.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 9881 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
56.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 10336 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
74.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 10354 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
29.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 10500 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
81.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 16332 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
48.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT K14 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
61.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT K2 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
84.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT K4 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
64.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT L1 assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
47.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT Vol assessed as inhibition of [3H] incorporation after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
37.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum W2 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S and I356T mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
52.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum D6 harboring Ppcrt I371R mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
58.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum FCM29 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S and I356T mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
98.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum FCR3 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S and I356T mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
53.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum PA harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S and I356T mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
80.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum HB3 harboring Ppcrt I371R mutant gene and Pfmdr1 Y184F mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum HB3
|
55.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum 106/1 harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S and I356T mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
69.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT Bres harboring Ppcrt M74I, N75E, K76T, A220S, Q271E, N326S and I356T mutant gene, Pmdr1 N86Y mutant gene and Pfmrp H191Y and S437A mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
46.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT Guy harboring Ppcrt K76T, A220S, N326D and I371R mutant gene, Pmdr1 T184FN, 1042D and D1246Y, mutant gene and Pfmrp H191Y and S437A mutant gene and Pfnhe-1 ms4760 microsatellite mutant assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
63.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT A4 harboring Ppcrt M74I, N75E, K76T, A220H, Q271E, N326S and I356T mutant gene, Pmdr1 Y184F, N1042D, D1246Y mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
75.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 31 harboring Ppcrt I371R mutant gene assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
48.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum IMT 8425 harboring Ppcrt I371R mutant gene and Pfnhe-1 ms4760 microsatellite mutant assessed as incorporation of [3]H hypoxanthine after 48 hrs by scintillation counter
|
Plasmodium falciparum
|
44.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Absence of association between piperaquine in vitro responses and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe genes in Plasmodium falciparum.
Year : 2010
Volume : 54
Issue : 9
First Page : 3537
Last Page : 3544
Authors : Briolant S, Henry M, Oeuvray C, Amalvict R, Baret E, Didillon E, Rogier C, Pradines B.
Abstract : We have analyzed the profiles of 23 of Plasmodium falciparum strains for their in vitro chemosusceptibilities to piperaquine (PPQ), dihydroartemisinin (DHA), chloroquine, monodesethylamodiaquine, quinine, mefloquine, lumefantrine, atovaquone, pyrimethamine, and doxycycline (DOX) in association with polymorphisms in genes involved in quinoline resistance (Plasmodium falciparum crt [pfcrt], pfmdr1, pfmrp, and pfnhe). The 50% inhibitory concentrations (IC(50)s) for PPQ ranged from 29 to 98 nM (geometric mean = 57.8 nM, 95% confidence interval [CI] = 51 to 65) and from 0.4 to 5.8 nM for DHA (geometric mean = 1.8 nM, 95% CI = 1.4 to 2.3). We found a significant positive correlation between the responses to PPQ and DHA (r(2) = 0.17; P = 0.0495) and between the responses to PPQ and DOX (r(2) = 0.41; P = 0.001). We did not find a significant association between the PPQ IC(50) (0.0525 < P < 0.9247) or the DHA IC(50) (0.0138 < P < 0.9018) and polymorphisms in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 genes. There was an absence of cross-resistance with quinolines, and the IC(50)s for PPQ and DHA were found to be unrelated to mutations in the pfcrt, pfmdr1, pfmrp, and pfnhe-1 transport protein genes, which are involved in quinoline antimalarial drug resistance. These results confirm the interest in and the efficacy of the combination of PPQ and DHA for areas in which parasites are resistant to chloroquine or other quinolines.
|
Antimalarial activity against Plasmodium falciparum at the ring stage infected in human erythrocytes assessed as growth inhibition by microscopic analysis using giemsa staining
|
Plasmodium falciparum
|
11.8
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium falciparum trophozoites infected in human erythrocytes assessed as growth inhibition by microscopic analysis using giemsa staining
|
Plasmodium falciparum
|
77.2
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium vivax at the ring stage infected in human erythrocytes assessed as growth inhibition by microscopic analysis using giemsa staining
|
Plasmodium vivax
|
14.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium vivax trophozoites infected in human erythrocytes assessed as growth inhibition by microscopic analysis using giemsa staining
|
Plasmodium vivax
|
21.7
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium falciparum infected in human erythrocytes assessed as growth inhibition by microscopic analysis using giemsa staining
|
Plasmodium falciparum
|
17.1
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium vivax infected in human erythrocytes assessed as growth inhibition by microscopic analysis using giemsa staining
|
Plasmodium vivax
|
24.8
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium vivax with >50% parasites at ring stage infected in human erythrocytes assessed as growth inhibition after 30 to 50 hrs by microscopic analysis using giemsa staining
|
Plasmodium vivax
|
19.6
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vitro activity of pyronaridine against multidrug-resistant Plasmodium falciparum and Plasmodium vivax.
Year : 2010
Volume : 54
Issue : 12
First Page : 5146
Last Page : 5150
Authors : Price RN, Marfurt J, Chalfein F, Kenangalem E, Piera KA, Tjitra E, Anstey NM, Russell B.
Abstract : Pyronaridine, a Mannich base antimalarial, has demonstrated high in vivo and in vitro efficacy against chloroquine-resistant Plasmodium falciparum. Although this drug has the potential to become a prominent artemisinin combination therapy, little is known about its efficacy against drug-resistant Plasmodium vivax. The in vitro antimalarial susceptibility of pyronaridine was assessed in multidrug-resistant P. vivax (n = 99) and P. falciparum (n = 90) isolates from Papua, Indonesia, using a schizont maturation assay. The median 50% inhibitory concentration (IC(50)) of pyronaridine was 1.92 nM (range, 0.24 to 13.8 nM) against P. falciparum and 2.58 nM (range, 0.13 to 43.6 nM) against P. vivax, with in vitro susceptibility correlating significantly with chloroquine, amodiaquine, and piperaquine (r(s) [Spearman's rank correlation coefficient] = 0.45 to 0.62; P < 0.001). P. falciparum parasites initially at trophozoite stage had higher IC(50)s of pyronaridine than those exposed at the ring stage (8.9 nM [range, 0.6 to 8.9 nM] versus 1.6 nM [range, 0.6 to 8.9 nM], respectively; P = 0.015), although this did not reach significance for P. vivax (4.7 nM [range, 1.4 to 18.7 nM] versus 2.5 nM [range, 1.4 to 15.6 nM], respectively; P = 0.085). The excellent in vitro efficacy of pyronaridine against both chloroquine-resistant P. vivax and P. falciparum highlights the suitability of the drug as a novel partner for artemisinin-based combination therapy in regions where the two species are coendemic.
|
Antimalarial activity against Plasmodium malariae trophozoite stage infected in red blood cells in presence of AB+ human serum by drug susceptibility assay
|
Plasmodium malariae
|
38.4
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vivo and in vitro efficacy of chloroquine against Plasmodium malariae and P. ovale in Papua, Indonesia.
Year : 2011
Volume : 55
Issue : 1
First Page : 197
Last Page : 202
Authors : Siswantoro H, Russell B, Ratcliff A, Prasetyorini B, Chalfein F, Marfurt J, Kenangalem E, Wuwung M, Piera KA, Ebsworth EP, Anstey NM, Tjitra E, Price RN.
Abstract : Reports of potential drug-resistant strains of Plasmodium malariae in western Indonesia raise concerns that chloroquine resistance may be emerging in P. malariae and P. ovale. In order to assess this, in vivo and in vitro efficacy studies were conducted in patients with monoinfection in Papua, Indonesia. Consecutive patients with uncomplicated malaria due to P. ovale or P. malariae were enrolled in a prospective clinical trial, provided with supervised chloroquine treatment, and followed for 28 days. Blood from patients with P. malariae or P. ovale parasitemia greater than 1,000 per microliter underwent in vitro antimalarial drug susceptibility testing using a modified schizont maturation assay. Of the 57 evaluable patients in the clinical study (P. malariae, n = 46; P. ovale, n = 11), none had recurrence with the same species during follow-up. The mean parasite reduction ratio at 48 h was 86 (95% confidence interval [CI], 57 to 114) for P. malariae and 150 (95% CI, 54 to 245) for P. ovale (P = 0.18). One patient infected with P. malariae, with 93% of parasites at the trophozoite stage, was still parasitemic on day 4. In vitro drug susceptibility assays were carried out successfully for 40 isolates (34 infected with P. malariae and 6 with P. ovale). The P. malariae infections at trophozoite stages had significantly higher chloroquine 50% effective concentrations (EC(50)s) (median, 127.9 nM [range, 7.9 to 2,980]) than those initially exposed at the ring stage (median, 14.0 nM [range, 3.5 to 27.0]; P = 0.01). The EC(50) for chloroquine in P. ovale was also higher in an isolate initially at the trophozoite stage (23.2 nM) than in the three isolates predominantly at ring stage (7.8 nM). Chloroquine retains adequate efficacy against P. ovale and P. malariae, but its marked stage specificity of action may account for reports of delayed parasite clearance times.
|
Antimalarial activity against Plasmodium malariae ring stage infected in red blood cells in presence of AB+ human serum by drug susceptibility assay
|
Plasmodium malariae
|
29.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vivo and in vitro efficacy of chloroquine against Plasmodium malariae and P. ovale in Papua, Indonesia.
Year : 2011
Volume : 55
Issue : 1
First Page : 197
Last Page : 202
Authors : Siswantoro H, Russell B, Ratcliff A, Prasetyorini B, Chalfein F, Marfurt J, Kenangalem E, Wuwung M, Piera KA, Ebsworth EP, Anstey NM, Tjitra E, Price RN.
Abstract : Reports of potential drug-resistant strains of Plasmodium malariae in western Indonesia raise concerns that chloroquine resistance may be emerging in P. malariae and P. ovale. In order to assess this, in vivo and in vitro efficacy studies were conducted in patients with monoinfection in Papua, Indonesia. Consecutive patients with uncomplicated malaria due to P. ovale or P. malariae were enrolled in a prospective clinical trial, provided with supervised chloroquine treatment, and followed for 28 days. Blood from patients with P. malariae or P. ovale parasitemia greater than 1,000 per microliter underwent in vitro antimalarial drug susceptibility testing using a modified schizont maturation assay. Of the 57 evaluable patients in the clinical study (P. malariae, n = 46; P. ovale, n = 11), none had recurrence with the same species during follow-up. The mean parasite reduction ratio at 48 h was 86 (95% confidence interval [CI], 57 to 114) for P. malariae and 150 (95% CI, 54 to 245) for P. ovale (P = 0.18). One patient infected with P. malariae, with 93% of parasites at the trophozoite stage, was still parasitemic on day 4. In vitro drug susceptibility assays were carried out successfully for 40 isolates (34 infected with P. malariae and 6 with P. ovale). The P. malariae infections at trophozoite stages had significantly higher chloroquine 50% effective concentrations (EC(50)s) (median, 127.9 nM [range, 7.9 to 2,980]) than those initially exposed at the ring stage (median, 14.0 nM [range, 3.5 to 27.0]; P = 0.01). The EC(50) for chloroquine in P. ovale was also higher in an isolate initially at the trophozoite stage (23.2 nM) than in the three isolates predominantly at ring stage (7.8 nM). Chloroquine retains adequate efficacy against P. ovale and P. malariae, but its marked stage specificity of action may account for reports of delayed parasite clearance times.
|
Antimalarial activity against Plasmodium ovale trophozoite stage infected in red blood cells in presence of AB+ human serum by drug susceptibility assay
|
Plasmodium ovale
|
7.57
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vivo and in vitro efficacy of chloroquine against Plasmodium malariae and P. ovale in Papua, Indonesia.
Year : 2011
Volume : 55
Issue : 1
First Page : 197
Last Page : 202
Authors : Siswantoro H, Russell B, Ratcliff A, Prasetyorini B, Chalfein F, Marfurt J, Kenangalem E, Wuwung M, Piera KA, Ebsworth EP, Anstey NM, Tjitra E, Price RN.
Abstract : Reports of potential drug-resistant strains of Plasmodium malariae in western Indonesia raise concerns that chloroquine resistance may be emerging in P. malariae and P. ovale. In order to assess this, in vivo and in vitro efficacy studies were conducted in patients with monoinfection in Papua, Indonesia. Consecutive patients with uncomplicated malaria due to P. ovale or P. malariae were enrolled in a prospective clinical trial, provided with supervised chloroquine treatment, and followed for 28 days. Blood from patients with P. malariae or P. ovale parasitemia greater than 1,000 per microliter underwent in vitro antimalarial drug susceptibility testing using a modified schizont maturation assay. Of the 57 evaluable patients in the clinical study (P. malariae, n = 46; P. ovale, n = 11), none had recurrence with the same species during follow-up. The mean parasite reduction ratio at 48 h was 86 (95% confidence interval [CI], 57 to 114) for P. malariae and 150 (95% CI, 54 to 245) for P. ovale (P = 0.18). One patient infected with P. malariae, with 93% of parasites at the trophozoite stage, was still parasitemic on day 4. In vitro drug susceptibility assays were carried out successfully for 40 isolates (34 infected with P. malariae and 6 with P. ovale). The P. malariae infections at trophozoite stages had significantly higher chloroquine 50% effective concentrations (EC(50)s) (median, 127.9 nM [range, 7.9 to 2,980]) than those initially exposed at the ring stage (median, 14.0 nM [range, 3.5 to 27.0]; P = 0.01). The EC(50) for chloroquine in P. ovale was also higher in an isolate initially at the trophozoite stage (23.2 nM) than in the three isolates predominantly at ring stage (7.8 nM). Chloroquine retains adequate efficacy against P. ovale and P. malariae, but its marked stage specificity of action may account for reports of delayed parasite clearance times.
|
Antimalarial activity against Plasmodium ovale ring stage infected in red blood cells in presence of AB+ human serum by drug susceptibility assay
|
Plasmodium ovale
|
10.2
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : In vivo and in vitro efficacy of chloroquine against Plasmodium malariae and P. ovale in Papua, Indonesia.
Year : 2011
Volume : 55
Issue : 1
First Page : 197
Last Page : 202
Authors : Siswantoro H, Russell B, Ratcliff A, Prasetyorini B, Chalfein F, Marfurt J, Kenangalem E, Wuwung M, Piera KA, Ebsworth EP, Anstey NM, Tjitra E, Price RN.
Abstract : Reports of potential drug-resistant strains of Plasmodium malariae in western Indonesia raise concerns that chloroquine resistance may be emerging in P. malariae and P. ovale. In order to assess this, in vivo and in vitro efficacy studies were conducted in patients with monoinfection in Papua, Indonesia. Consecutive patients with uncomplicated malaria due to P. ovale or P. malariae were enrolled in a prospective clinical trial, provided with supervised chloroquine treatment, and followed for 28 days. Blood from patients with P. malariae or P. ovale parasitemia greater than 1,000 per microliter underwent in vitro antimalarial drug susceptibility testing using a modified schizont maturation assay. Of the 57 evaluable patients in the clinical study (P. malariae, n = 46; P. ovale, n = 11), none had recurrence with the same species during follow-up. The mean parasite reduction ratio at 48 h was 86 (95% confidence interval [CI], 57 to 114) for P. malariae and 150 (95% CI, 54 to 245) for P. ovale (P = 0.18). One patient infected with P. malariae, with 93% of parasites at the trophozoite stage, was still parasitemic on day 4. In vitro drug susceptibility assays were carried out successfully for 40 isolates (34 infected with P. malariae and 6 with P. ovale). The P. malariae infections at trophozoite stages had significantly higher chloroquine 50% effective concentrations (EC(50)s) (median, 127.9 nM [range, 7.9 to 2,980]) than those initially exposed at the ring stage (median, 14.0 nM [range, 3.5 to 27.0]; P = 0.01). The EC(50) for chloroquine in P. ovale was also higher in an isolate initially at the trophozoite stage (23.2 nM) than in the three isolates predominantly at ring stage (7.8 nM). Chloroquine retains adequate efficacy against P. ovale and P. malariae, but its marked stage specificity of action may account for reports of delayed parasite clearance times.
|
Antimalarial activity against trophozoites stage of Plasmodium vivax assessed as parasites growth inhibition using giemsa staining after 24 to 56 hrs by microscopic analysis in presence of 20% human serum
|
Plasmodium vivax
|
15.9
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against ring stage of Plasmodium vivax assessed as parasites growth inhibition using giemsa staining after 24 to 56 hrs by microscopic analysis in presence of 20% human serum
|
Plasmodium vivax
|
15.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against trophozoites stage of Plasmodium falciparum assessed as parasites growth inhibition using giemsa staining after 24 to 56 hrs by microscopic analysis in presence of 10% human serum
|
Plasmodium falciparum
|
87.6
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against ring stage of Plasmodium falciparum assessed as parasites growth inhibition using giemsa staining after 24 to 56 hrs by microscopic analysis in presence of 10% human serum
|
Plasmodium falciparum
|
11.5
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against Plasmodium vivax assessed as parasites growth inhibition using giemsa staining after 24 to 56 hrs by microscopic analysis in presence of 20% human serum
|
Plasmodium vivax
|
13.2
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against Plasmodium falciparum assessed as parasites growth inhibition using giemsa staining after 24 to 56 hrs by microscopic analysis in presence of 10% human serum
|
Plasmodium falciparum
|
10.8
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum 3D7 assessed as inhibition of [3H]hypoxanthine incorporation
|
Plasmodium falciparum
|
3.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum K1 assessed as inhibition of [3H]hypoxanthine incorporation
|
Plasmodium falciparum K1
|
11.0
nM
|
|
Journal : Antimicrob. Agents Chemother.
Title : Ex vivo activity of histone deacetylase inhibitors against multidrug-resistant clinical isolates of Plasmodium falciparum and P. vivax.
Year : 2011
Volume : 55
Issue : 3
First Page : 961
Last Page : 966
Authors : Marfurt J, Chalfein F, Prayoga P, Wabiser F, Kenangalem E, Piera KA, Fairlie DP, Tjitra E, Anstey NM, Andrews KT, Price RN.
Abstract : Histone acetylation plays an important role in regulating gene transcription and silencing in Plasmodium falciparum. Histone deacetylase (HDAC) inhibitors, particularly those of the hydroxamate class, have been shown to have potent in vitro activity against drug-resistant and -sensitive laboratory strains of P. falciparum, raising their potential as a new class of antimalarial compounds. In the current study, stage-specific ex vivo susceptibility profiles of representative hydroxamate-based HDAC inhibitors suberoylanilide hydroxamic acid (SAHA), 2-ASA-9, and 2-ASA-14 (2-ASA-9 and 2-ASA-14 are 2-aminosuberic acid-based HDAC inhibitors) were assessed in multidrug-resistant clinical isolates of P. falciparum (n = 24) and P. vivax (n = 25) from Papua, Indonesia, using a modified schizont maturation assay. Submicromolar concentrations of SAHA, 2-ASA-9, and 2-ASA-14 inhibited the growth of both P. falciparum (median 50% inhibitory concentrations [IC₅₀s] of 310, 533, and 266 nM) and P. vivax (median IC₅₀s of 170, 503, and 278 nM). Inverse correlation patterns between HDAC inhibitors and chloroquine for P. falciparum and mefloquine for P. vivax indicate species-specific susceptibility profiles for HDAC inhibitors. These HDAC inhibitors were also found to be potent ex vivo against P. vivax schizont maturation, comparable to that in P. falciparum, suggesting that HDAC inhibitors may be promising candidates for antimalarial therapy in geographical locations where both species are endemic. Further studies optimizing the selectivity and in vivo efficacy of HDAC inhibitors in Plasmodium spp. and defining drug interaction with common antimalarial compounds are warranted to investigate the role of HDAC inhibitors in antimalarial therapy.
|
Antiplasmodial activity against multidrug-resistant Plasmodium falciparum W2 infected in human erythrocytes after 72 hrs by ELISA
|
Plasmodium falciparum
|
12.5
nM
|
|
Journal : Bioorg. Med. Chem. Lett.
Title : Recent advances in malaria drug discovery.
Year : 2013
Volume : 23
Issue : 10
First Page : 2829
Last Page : 2843
Authors : Biamonte MA, Wanner J, Le Roch KG.
Abstract : This digest covers some of the most relevant progress in malaria drug discovery published between 2010 and 2012. There is an urgent need to develop new antimalarial drugs. Such drugs can target the blood stage of the disease to alleviate the symptoms, the liver stage to prevent relapses, and the transmission stage to protect other humans. The pipeline for the blood stage is becoming robust, but this should not be a source of complacency, as the current therapies set a high standard. Drug discovery efforts directed towards the liver and transmission stages are in their infancy but are receiving increasing attention as targeting these stages could be instrumental in eradicating malaria.
|
Inhibition of CYP3A4 (unknown origin)
|
Homo sapiens
|
90.0
nM
|
|
Journal : J Med Chem
Title : The Development Process for Discovery and Clinical Advancement of Modern Antimalarials.
Year : 2019
Volume : 62
Issue : 23
First Page : 10526
Last Page : 10562
Authors : Ashton TD, Devine SM, Möhrle JJ, Laleu B, Burrows JN, Charman SA, Creek DJ, Sleebs BE.
Abstract : Malaria is a devastating disease caused by <i>Plasmodium</i> parasites, resulting in approximately 435000 deaths in 2018. The impact of malaria is compounded by the emergence of widespread resistance to current antimalarial therapies. Recently, a new strategy was initiated to screen small molecule collections against the <i>Plasmodium</i> parasite enabling the identification of new antimalarial chemotypes with novel modes of action. This initiative ushered in the modern era of antimalarial drug development, and as a result, numerous lead candidates are advancing toward or are currently in human clinical trials. In this Perspective, we describe the development pathway of four of the most clinically advanced modern antimalarials, KAE609, KAF156, DSM265, and MMV048. Additionally, the mechanism of action and life-cycle stage specificity of the four antimalarials is discussed in relation to aligning with global strategies to treat and eliminate malaria. This perspective serves as a guide to the expectations of modern antimalarial drug development.
|
Antimalarial activity against multidrug-resistant Plasmodium falciparum Dd2 infected in human erythrocytes by SYBR green 1-based fluorescence assay
|
Plasmodium falciparum
|
9.0
nM
|
|
Journal : J Med Chem
Title : Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials.
Year : 2019
Volume : 62
Issue : 7
First Page : 3475
Last Page : 3502
Authors : Dodean RA, Kancharla P, Li Y, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Huezo SJ, Rasmussen SA, Stephens MT, Tan JC, Cooper RA, Smilkstein MJ, Pou S, Winter RW, Riscoe MK, Kelly JX.
Abstract : Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
|
Antimalarial activity against drug-resistant Plasmodium falciparum Dd2 harboring V259L mutant infected in human erythrocytes after 72 hrs by SYBR green 1-based fluorescence assay
|
Plasmodium falciparum
|
7.1
nM
|
|
Journal : J Med Chem
Title : Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials.
Year : 2019
Volume : 62
Issue : 7
First Page : 3475
Last Page : 3502
Authors : Dodean RA, Kancharla P, Li Y, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Huezo SJ, Rasmussen SA, Stephens MT, Tan JC, Cooper RA, Smilkstein MJ, Pou S, Winter RW, Riscoe MK, Kelly JX.
Abstract : Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
|
Antimalarial activity against drug-resistant Plasmodium falciparum Dd2 harboring M133I/A138T double mutant infected in human erythrocytes after 72 hrs by SYBR green 1-based fluorescence assay
|
Plasmodium falciparum
|
7.4
nM
|
|
Journal : J Med Chem
Title : Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials.
Year : 2019
Volume : 62
Issue : 7
First Page : 3475
Last Page : 3502
Authors : Dodean RA, Kancharla P, Li Y, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Huezo SJ, Rasmussen SA, Stephens MT, Tan JC, Cooper RA, Smilkstein MJ, Pou S, Winter RW, Riscoe MK, Kelly JX.
Abstract : Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
|
Antimalarial activity against drug-resistant Plasmodium falciparum Dd2 harboring M133I mutant infected in human erythrocytes after 72 hrs by SYBR green 1-based fluorescence assay
|
Plasmodium falciparum
|
10.0
nM
|
|
Journal : J Med Chem
Title : Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials.
Year : 2019
Volume : 62
Issue : 7
First Page : 3475
Last Page : 3502
Authors : Dodean RA, Kancharla P, Li Y, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Huezo SJ, Rasmussen SA, Stephens MT, Tan JC, Cooper RA, Smilkstein MJ, Pou S, Winter RW, Riscoe MK, Kelly JX.
Abstract : Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
|
Antimalarial activity against Plasmodium falciparum 3D7 infected in human erythrocytes after 72 hrs by SYBR green 1-based fluorescence assay
|
Plasmodium falciparum
|
7.2
nM
|
|
Journal : J Med Chem
Title : Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials.
Year : 2019
Volume : 62
Issue : 7
First Page : 3475
Last Page : 3502
Authors : Dodean RA, Kancharla P, Li Y, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Huezo SJ, Rasmussen SA, Stephens MT, Tan JC, Cooper RA, Smilkstein MJ, Pou S, Winter RW, Riscoe MK, Kelly JX.
Abstract : Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
|
Antimalarial activity against drug-resistant Plasmodium falciparum 3D7 harboring A82T/V259L double mutant infected in human erythrocytes after 72 hrs by SYBR green 1-based fluorescence assay
|
Plasmodium falciparum
|
5.0
nM
|
|
Journal : J Med Chem
Title : Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials.
Year : 2019
Volume : 62
Issue : 7
First Page : 3475
Last Page : 3502
Authors : Dodean RA, Kancharla P, Li Y, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Huezo SJ, Rasmussen SA, Stephens MT, Tan JC, Cooper RA, Smilkstein MJ, Pou S, Winter RW, Riscoe MK, Kelly JX.
Abstract : Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
|
Antimalarial activity against chloroquine-sensitive Plasmodium falciparum FC27 infected in human RBC assessed as reduction in parasite growth after 35 to 56 hrs by nucleic acid staining based flow cytometry
|
Plasmodium falciparum
|
38.5
nM
|
|
Journal : J Med Chem
Title : 3,3'-Disubstituted 5,5'-Bi(1,2,4-triazine) Derivatives with Potent in Vitro and in Vivo Antimalarial Activity.
Year : 2019
Volume : 62
Issue : 5
First Page : 2485
Last Page : 2498
Authors : Xue L, Shi DH, Harjani JR, Huang F, Beveridge JG, Dingjan T, Ban K, Diab S, Duffy S, Lucantoni L, Fletcher S, Chiu FCK, Blundell S, Ellis K, Ralph SA, Wirjanata G, Teguh S, Noviyanti R, Chavchich M, Creek D, Price RN, Marfurt J, Charman SA, Cuellar ME, Strasser JM, Dahlin JL, Walters MA, Edstein MD, Avery VM, Baell JB.
Abstract : A series of 3,3'-disubstituted 5,5'-bi(1,2,4-triazine) derivatives was synthesized and screened against the erythrocytic stage of Plasmodium falciparum 3D7 line. The most potent dimer, 6k, with an IC50 (50% inhibitory concentration) of 0.008 μM, had high in vitro potency against P. falciparum lines resistant to chloroquine (W2, IC50 = 0.0047 ± 0.0011 μM) and artemisinin (MRA1240, IC50 = 0.0086 ± 0.0010 μM). Excellent ex vivo potency of 6k was shown against clinical field isolates of both P. falciparum (IC50 = 0.022-0.034 μM) and Plasmodium vivax (IC50 = 0.0093-0.031 μM) from the blood of outpatients with uncomplicated malaria. Despite 6k being cleared relatively rapidly in mice, it suppressed parasitemia in the Peters 4-day test, with a mean ED50 value (50% effective dose) of 1.47 mg kg-1 day-1 following oral administration. The disubstituted triazine dimer 6k represents a new class of orally available antimalarial compounds of considerable interest for further development.
|
Antimalarial activity against chloroquine-resistant Plasmodium falciparum K1 infected in human RBC assessed as reduction in parasite growth after 35 to 56 hrs by nucleic acid staining based flow cytometry
|
Plasmodium falciparum
|
50.8
nM
|
|
Journal : J Med Chem
Title : 3,3'-Disubstituted 5,5'-Bi(1,2,4-triazine) Derivatives with Potent in Vitro and in Vivo Antimalarial Activity.
Year : 2019
Volume : 62
Issue : 5
First Page : 2485
Last Page : 2498
Authors : Xue L, Shi DH, Harjani JR, Huang F, Beveridge JG, Dingjan T, Ban K, Diab S, Duffy S, Lucantoni L, Fletcher S, Chiu FCK, Blundell S, Ellis K, Ralph SA, Wirjanata G, Teguh S, Noviyanti R, Chavchich M, Creek D, Price RN, Marfurt J, Charman SA, Cuellar ME, Strasser JM, Dahlin JL, Walters MA, Edstein MD, Avery VM, Baell JB.
Abstract : A series of 3,3'-disubstituted 5,5'-bi(1,2,4-triazine) derivatives was synthesized and screened against the erythrocytic stage of Plasmodium falciparum 3D7 line. The most potent dimer, 6k, with an IC50 (50% inhibitory concentration) of 0.008 μM, had high in vitro potency against P. falciparum lines resistant to chloroquine (W2, IC50 = 0.0047 ± 0.0011 μM) and artemisinin (MRA1240, IC50 = 0.0086 ± 0.0010 μM). Excellent ex vivo potency of 6k was shown against clinical field isolates of both P. falciparum (IC50 = 0.022-0.034 μM) and Plasmodium vivax (IC50 = 0.0093-0.031 μM) from the blood of outpatients with uncomplicated malaria. Despite 6k being cleared relatively rapidly in mice, it suppressed parasitemia in the Peters 4-day test, with a mean ED50 value (50% effective dose) of 1.47 mg kg-1 day-1 following oral administration. The disubstituted triazine dimer 6k represents a new class of orally available antimalarial compounds of considerable interest for further development.
|
Antimalarial activity against multidrug-resistant Plasmodium falciparum clinical isolates infected assessed as reduction in parasite growth after 35 to 56 hrs by nucleic acid staining based flow cytometry
|
Plasmodium falciparum
|
20.7
nM
|
|
Journal : J Med Chem
Title : 3,3'-Disubstituted 5,5'-Bi(1,2,4-triazine) Derivatives with Potent in Vitro and in Vivo Antimalarial Activity.
Year : 2019
Volume : 62
Issue : 5
First Page : 2485
Last Page : 2498
Authors : Xue L, Shi DH, Harjani JR, Huang F, Beveridge JG, Dingjan T, Ban K, Diab S, Duffy S, Lucantoni L, Fletcher S, Chiu FCK, Blundell S, Ellis K, Ralph SA, Wirjanata G, Teguh S, Noviyanti R, Chavchich M, Creek D, Price RN, Marfurt J, Charman SA, Cuellar ME, Strasser JM, Dahlin JL, Walters MA, Edstein MD, Avery VM, Baell JB.
Abstract : A series of 3,3'-disubstituted 5,5'-bi(1,2,4-triazine) derivatives was synthesized and screened against the erythrocytic stage of Plasmodium falciparum 3D7 line. The most potent dimer, 6k, with an IC50 (50% inhibitory concentration) of 0.008 μM, had high in vitro potency against P. falciparum lines resistant to chloroquine (W2, IC50 = 0.0047 ± 0.0011 μM) and artemisinin (MRA1240, IC50 = 0.0086 ± 0.0010 μM). Excellent ex vivo potency of 6k was shown against clinical field isolates of both P. falciparum (IC50 = 0.022-0.034 μM) and Plasmodium vivax (IC50 = 0.0093-0.031 μM) from the blood of outpatients with uncomplicated malaria. Despite 6k being cleared relatively rapidly in mice, it suppressed parasitemia in the Peters 4-day test, with a mean ED50 value (50% effective dose) of 1.47 mg kg-1 day-1 following oral administration. The disubstituted triazine dimer 6k represents a new class of orally available antimalarial compounds of considerable interest for further development.
|
Antimalarial activity against multidrug-resistant Plasmodium vivax clinical isolates assessed as reduction in parasite growth after 35 to 56 hrs by nucleic acid staining based flow cytometry
|
Plasmodium vivax
|
45.2
nM
|
|
Journal : J Med Chem
Title : 3,3'-Disubstituted 5,5'-Bi(1,2,4-triazine) Derivatives with Potent in Vitro and in Vivo Antimalarial Activity.
Year : 2019
Volume : 62
Issue : 5
First Page : 2485
Last Page : 2498
Authors : Xue L, Shi DH, Harjani JR, Huang F, Beveridge JG, Dingjan T, Ban K, Diab S, Duffy S, Lucantoni L, Fletcher S, Chiu FCK, Blundell S, Ellis K, Ralph SA, Wirjanata G, Teguh S, Noviyanti R, Chavchich M, Creek D, Price RN, Marfurt J, Charman SA, Cuellar ME, Strasser JM, Dahlin JL, Walters MA, Edstein MD, Avery VM, Baell JB.
Abstract : A series of 3,3'-disubstituted 5,5'-bi(1,2,4-triazine) derivatives was synthesized and screened against the erythrocytic stage of Plasmodium falciparum 3D7 line. The most potent dimer, 6k, with an IC50 (50% inhibitory concentration) of 0.008 μM, had high in vitro potency against P. falciparum lines resistant to chloroquine (W2, IC50 = 0.0047 ± 0.0011 μM) and artemisinin (MRA1240, IC50 = 0.0086 ± 0.0010 μM). Excellent ex vivo potency of 6k was shown against clinical field isolates of both P. falciparum (IC50 = 0.022-0.034 μM) and Plasmodium vivax (IC50 = 0.0093-0.031 μM) from the blood of outpatients with uncomplicated malaria. Despite 6k being cleared relatively rapidly in mice, it suppressed parasitemia in the Peters 4-day test, with a mean ED50 value (50% effective dose) of 1.47 mg kg-1 day-1 following oral administration. The disubstituted triazine dimer 6k represents a new class of orally available antimalarial compounds of considerable interest for further development.
|
Antimalarial activity against Plasmodium falciparum clinical isolates measured after 72 hrs by SYBR green dye based fluorescence assay
|
Plasmodium falciparum
|
5.9
nM
|
|
Journal : J Med Chem
Title : Lead Optimization of Second-Generation Acridones as Broad-Spectrum Antimalarials.
Year : 2020
Volume : 63
Issue : 11
First Page : 6179
Last Page : 6202
Authors : Kancharla P, Dodean RA, Li Y, Pou S, Pybus B, Melendez V, Read L, Bane CE, Vesely B, Kreishman-Deitrick M, Black C, Li Q, Sciotti RJ, Olmeda R, Luong TL, Gaona H, Potter B, Sousa J, Marcsisin S, Caridha D, Xie L, Vuong C, Zeng Q, Zhang J, Zhang P, Lin H, Butler K, Roncal N, Gaynor-Ohnstad L, Leed SE, Nolan C, Ceja FG, Rasmussen SA, Tumwebaze PK, Rosenthal PJ, Mu J, Bayles BR, Cooper RA, Reynolds KA, Smilkstein MJ, Riscoe MK, Kelly JX.
Abstract : The global impact of malaria remains staggering despite extensive efforts to eradicate the disease. With increasing drug resistance and the absence of a clinically available vaccine, there is an urgent need for novel, affordable, and safe drugs for prevention and treatment of malaria. Previously, we described a novel antimalarial acridone chemotype that is potent against both blood-stage and liver-stage malaria parasites. Here, we describe an optimization process that has produced a second-generation acridone series with significant improvements in efficacy, metabolic stability, pharmacokinetics, and safety profiles. These findings highlight the therapeutic potential of dual-stage targeting acridones as novel drug candidates for further preclinical development.
|
Antimalarial activity against Plasmodium falciparum infected in human erythrocytes assessed as inhibition of [G-3H]hypoxanthine uptake incubated for 42 hrs by liquid scintillation spectrometry
|
Plasmodium falciparum
|
81.3
nM
|
|
Journal : Eur J Med Chem
Title : Current progress in antimalarial pharmacotherapy and multi-target drug discovery.
Year : 2020
Volume : 188
First Page : 111983
Last Page : 111983
Authors : Tibon NS,Ng CH,Cheong SL
Abstract : Discovery and development of antimalarial drugs have long been dominated by single-target therapy. Continuous effort has been made to explore and identify different targets in malaria parasite crucial for the malaria treatment. The single-target drug therapy was initially successful, but it was later supplanted by combination therapy with multiple drugs to overcome drug resistance. Emergence of resistant strains even against the combination therapy has warranted a review of current antimalarial pharmacotherapy. This has led to the development of the new concept of covalent biotherapy, in which two or more pharmacophores are chemically bound to produce hybrid antimalarial drugs with multi-target functionalities. Herein, the review initially details the current pharmacotherapy for malaria as well as the conventional and novel targets of importance identified in the malaria parasite. Then, the rationale of multi-targeted therapy for malaria, approaches taken to develop the multi-target antimalarial hybrids, and the examples of hybrid molecules are comprehensively enumerated and discussed.
