Thursday, February 26, 2026

GSK agrees to acquire 35Pharma, adding pulmonary hypertension asset HS235

GSK said on 25 February 2026 it has entered an agreement to acquire 35Pharma Inc., a Canada-based private clinical-stage biotech focused on protein therapeutics. The deal centres on HS235, an activin signalling inhibitor in clinical development for cardiopulmonary diseases.

Target indications and upcoming trials

According to GSK, HS235 has completed a phase I trial in healthy volunteers. Studies in pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with heart failure with preserved ejection fraction (PH-HFpEF) are expected to begin imminently.

Pulmonary hypertension is described as a progressive condition with limited treatment options. GSK estimates around 82 million people are affected worldwide across different forms. By 2032, the global market for PH therapies is forecast at $18 billion, with activin signalling inhibitors projected to represent about half of that total based on consensus estimates.

Design goal: selectivity and potential bleeding risk reduction

HS235 targets the activin receptor signalling pathway, a clinically validated target in pulmonary hypertension. GSK said the molecule is designed to reduce binding to BMP9 and BMP10, ligands associated with adverse events including bleeding and telangiectasia. The company positions the programme as a potential way to mitigate a key limitation of existing PH therapies, particularly for patients who also require anticoagulant or antiplatelet treatment.

Potential metabolic effects highlighted

GSK also pointed to potential metabolic effects linked to HS235’s mechanism. Early clinical observations cited by the company include fat-selective weight loss, preservation of lean mass and improved insulin sensitivity, alongside changes in inflammatory markers and adipokines. GSK argues these features could be clinically relevant given the prevalence of obesity and insulin resistance in PH patient populations.

Financial terms and closing conditions

Under the agreement, GSK plans to acquire 100% of 35Pharma’s equity for $950 million, payable in cash at closing. Completion is subject to customary conditions, including regulatory clearances in the US and Canada and a filing under the Investment Canada Act.