GSK Expands Cardiopulmonary Research Portfolio with Planned Acquisition of 35Pharma and HS235 Therapy

GSK Expands Cardiopulmonary Research Portfolio with Planned Acquisition of 35Pharma and HS235 Therapy

(IN BRIEF) GSK has entered an agreement to acquire Canadian biotechnology company 35Pharma for $950 million in order to strengthen its pipeline of therapies for pulmonary hypertension and related cardiopulmonary diseases. The acquisition includes HS235, an investigational activin signalling inhibitor that has completed Phase I studies and is expected to move into patient trials. HS235 is designed to reduce bleeding risks compared to existing treatments and may also provide metabolic benefits such as improved insulin sensitivity and fat-selective weight loss. The transaction supports GSK’s strategy to expand its Respiratory, Immunology and Inflammation portfolio and remains subject to regulatory approvals in the United States and Canada.

(PRESS RELEASE) LONDON, 26-Feb-2026 — /EuropaWire/ — GSK plc has agreed to acquire the Canadian clinical-stage biotechnology company 35Pharma Inc., adding the investigational therapy HS235 to its development pipeline. The acquisition strengthens GSK’s Respiratory, Immunology and Inflammation portfolio by introducing a potential best-in-class activin signalling inhibitor designed to treat cardiopulmonary conditions, particularly pulmonary hypertension.

HS235 has already completed Phase I clinical studies in healthy volunteers, and further clinical trials are expected to begin soon in patients with pulmonary arterial hypertension and pulmonary hypertension linked to heart failure with preserved ejection fraction. Pulmonary hypertension is a serious and progressive disease characterized by elevated blood pressure in the lungs, often leading to heart failure. Despite affecting tens of millions of people worldwide, treatment options remain limited and long-term survival rates remain low.

The investigational therapy targets the activin receptor signalling pathway, an established therapeutic mechanism in pulmonary hypertension. HS235 has been engineered for greater selectivity than current therapies, with reduced interaction with BMP9 and BMP10 proteins that have been associated with adverse effects such as bleeding and vascular abnormalities. This selectivity could help lower bleeding risk, an important consideration for patients who often require anticoagulant or antiplatelet therapy.

Early clinical findings also indicate that HS235 may offer metabolic benefits, including reductions in body fat while maintaining lean muscle mass and improving insulin sensitivity. These effects may be particularly relevant for pulmonary hypertension patients, among whom metabolic disorders such as obesity and insulin resistance are common. The therapy’s combined vascular and metabolic profile could open additional development opportunities across chronic diseases affecting the lungs, liver and kidneys.

Tony Wood, Chief Scientific Officer at GSK, said the addition of HS235 broadens the company’s research pipeline with a differentiated therapy designed to improve vascular health and metabolic outcomes for patients with pulmonary hypertension. Ilia Tikhomirov, Chief Executive Officer of 35Pharma, noted that advances in scientific understanding of pulmonary hypertension have created new opportunities for disease-modifying treatments and said collaboration with GSK will help accelerate development of HS235.

Under the agreement, GSK will purchase all outstanding shares of 35Pharma for $950 million in cash. Completion of the transaction remains subject to regulatory approvals in the United States and Canada, including clearances under the Hart-Scott-Rodino Act and the Canadian Competition Act, as well as a review under the Investment Canada Act.

Pulmonary hypertension includes several forms, such as pulmonary arterial hypertension and pulmonary hypertension associated with heart failure. The global market for pulmonary hypertension therapies is expected to grow significantly in the coming years, with activin signalling inhibitors projected to represent a major share of future treatments.

About pulmonary hypertension

There are different types of PH such as Pulmonary Arterial Hypertension (PAH) and PH due to Heart Failure with preserved Ejection fraction (PH-HFpEF). PH is treated in specialised academic centres by pulmonologists and cardiologists, where PH programs sit within larger lung, respiratory and critical care centres. Around 82 million people worldwide are affected by PH and in the US, the addressable patient population for PAH and PH-HFpEF is approximately 100,000 people.1,4,5

About 35Pharma Inc.

35Pharma is a clinical-stage biopharmaceutical company developing novel TGF-beta superfamily therapeutics. 35Pharma’s lead candidate, HS235, is being developed for the treatment of cardiopulmonary diseases with clinical trials initiated in Pulmonary Arterial Hypertension and PH due to Heart Failure with preserved Ejection fraction. For more information visit www.35pharma.com

About GSK

GSK is a global biopharma company with a purpose to unite science, technology, and talent to get ahead of disease together. Find out more at www.gsk.com.

Cautionary statement regarding forward-looking statements

GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Such factors include, but are not limited to, those described in the “Risk Factors” section in GSK’s Annual Report on Form 20-F for 2024, and GSK’s Q4 Results for 2025.

References

1. Humbert, M. et al. (2022) 2022 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension, European Heart Journal, 43(38), pp. 3618–3731. doi:10.1093/eurheartj/ehac237.
2. Caravita S, Faini A, D’Araujo SC, et al. Clinical phenotypes and outcomes of pulmonary hypertension due to left heart disease: Role of the pre-capillary component. PLOS ONE. 2018;13(6):e0199164. doi:10.1371/journal.pone.0199164.
3. Evaluate Pharma consensus estimate; accessed Feb 2026.
4. Leary, Peter J et al. The Lancet Respiratory Medicine, Volume 13, Issue 1, 69-79.
5. GSK Internal data.

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SOURCE: GlaxoSmithKline plc