# FDA Approves Generic Bosentan The FDA has approved Zydus Pharmaceuticals USA Inc.'s generic formulation of bosentan, an endothelin receptor antagonist used to treat pulmonary arterial hypertension, potentially expanding treatment access and reducing costs for patients while intensifying competition in the pulmonary hypertension drug market. The approval of the oral generic version is expected to increase pricing pressure on the branded Tracleer and other competing therapies in this therapeutic category.