 Gossamer Bio Inc stock lost three quarters of its value today as the market questioned the performance of the companys experimental hypertension drug in a Phase 2 clinical trial despite an upbeat assessment from the company. We are very pleased to share that seralutinib significantly improved hemodynamic, biomarker, and right heart structural and functional measures in a heavily treated pulmonary arterial hypertension patient population, said Faheem Hasnain, CEO of Gossamer. 