GMA301B

GMA301B (also identified in some sources as GMA201B) is a humanized monoclonal antibody being developed by Gmax Biopharm International for the treatment of pulmonary arterial hypertension (PAH) in pediatric patients. The drug acts as an antagonist of the endothelin receptor A (ETA), a G-protein coupled receptor (GPCR) that mediates the potent vasoconstrictive and mitogenic effects of endothelin-1. By selectively blocking ETA, GMA301B aims to reduce pulmonary vascular resistance and prevent the vascular remodeling associated with PAH progression. GMA301B is the pediatric-specific development program derived from the parent compound GMA301, which is also being developed as GMA301A for adult patients. The antibody is designed for a long half-life to support infrequent dosing schedules.