Journal : J Med Chem
Title : Discovery of Dihydrobenzoxazepinone (GS-6615) Late Sodium Current Inhibitor (Late Ii), a Phase II Agent with Demonstrated Preclinical Anti-Ischemic and Antiarrhythmic Properties.
Year : 2016
Volume : 59
Issue : 19.0
First Page : 9005
Last Page : 9017
Authors : Zablocki JA,Elzein E,Li X,Koltun DO,Parkhill EQ,Kobayashi T,Martinez R,Corkey B,Jiang H,Perry T,Kalla R,Notte GT,Saunders O,Graupe M,Lu Y,Venkataramani C,Guerrero J,Perry J,Osier M,Strickley R,Liu G,Wang WQ,Hu L,Li XJ,El-Bizri N,Hirakawa R,Kahlig K,Xie C,Li CH,Dhalla AK,Rajamani S,Mollova N,Soohoo D,Lepist EI,Murray B,Rhodes G,Belardinelli L,Desai MC
Abstract : Late sodium current (late I) is enhanced during ischemia by reactive oxygen species (ROS) modifying the Na 1.5 channel, resulting in incomplete inactivation. Compound 4 (GS-6615, eleclazine) a novel, potent, and selective inhibitor of late I, is currently in clinical development for treatment of long QT-3 syndrome (LQT-3), hypertrophic cardiomyopathy (HCM), and ventricular tachycardia-ventricular fibrillation (VT-VF). We will describe structure-activity relationship (SAR) leading to the discovery of 4 that is vastly improved from the first generation late I inhibitor 1 (ranolazine). Compound 4 was 42 times more potent than 1 in reducing ischemic burden in vivo (S-T segment elevation, 15 min left anteriorior descending, LAD, occlusion in rabbits) with EC values of 190 and 8000 nM, respectively. Compound 4 represents a new class of potent late I inhibitors that will be useful in delineating the role of inhibitors of this current in the treatment of patients.