GSK agreed on 25 February to acquire 35Pharma, a privately held Montreal biotech developing protein-based therapies, for $950m in cash.
Why GSK plc is buying 35Pharma Inc.
The purchase gives GSK HS235, a potential best-in-class activin signalling inhibitor for pulmonary hypertension. The activin pathway is clinically validated in the disease, and HS235's selectivity may lower the risk of bleeding, pericardial effusion and dose-limiting haemoglobin increases seen with existing pulmonary arterial hypertension treatments. GSK has cited forecasts that the pulmonary hypertension market will reach $18bn by 2032, with roughly half expected to come from activin signalling inhibitors.
Deal terms and financing
GSK agreed to pay $950m in cash for 100% of 35Pharma. Its second-quarter results put total consideration at $1.0bn, comprising an upfront payment of $987m after working capital and other closing adjustments and $34m of deferred consideration; net of cash acquired, the investment was $944m.
Regulatory approvals and timing
Completion required clearance under the US Hart-Scott-Rodino Act and Canada's Competition Act and a filing under the Investment Canada Act, Lexpert reported. GSK completed the acquisition on 14 April 2026.
Market context
HS235 has finished Phase I trials in healthy volunteers, with proof-of-concept studies planned in pulmonary arterial hypertension and in pulmonary hypertension due to heart failure with preserved ejection fraction. The deal followed GSK's purchase of RAPT Therapeutics and forms part of a pipeline push under chief executive Luke Miels.
