On April 15, 2026, GSK plc completed its acquisition of 35Pharma Inc., a Montréal-based, private, clinical-stage biopharmaceutical company specializing in the development of novel protein-based therapeutics, for US$950 million in cash. The transaction, first announced on February 25, 2026, gives GSK full ownership of 35Pharma and its pipeline, headlined by HS235, a potential best-in-class investigational medicine for the treatment of pulmonary hypertension. HS235 targets the activin receptor signalling pathway, a clinically validated therapeutic target, and is engineered for enhanced selectivity that may reduce the risk of bleeding, pericardial effusion, and dose-limiting increases in haemoglobin associated with current pulmonary arterial hypertension treatments. The molecule has completed Phase I healthy volunteer trials, with proof-of-concept studies expected to begin in pulmonary arterial hypertension and in pulmonary hypertension due to heart failure with preserved ejection fraction. GSK has cited forecasts that the global market for pulmonary hypertension therapies will grow to US$18 billion by 2032, with activin signalling inhibitors expected to account for roughly half of that total. The acquisition adds HS235 to GSK's Respiratory, Immunology and Inflammation pipeline and follows the company's broader push under chief executive officer Luke Miels to expand its pipeline. Completion of the all-cash transaction was subject to customary conditions, including clearance under the Hart-Scott-Rodino Act in the United States and the Competition Act in Canada, together with a filing under the Investment Canada Act.