GSK acquires 35Pharma for $950M, adding Phase I-completed HS235 a selective activin inhibitor for PAH and PH-HFpEF with reduced bleeding risk and metabolic benefits to its pipeline amid a $18B PH market forecast by 2032.
Written By: Nikita Chaudhari, BPharm
Reviewed By: Pharmacally Editorial Team
GlaxoSmithKline announced its agreement to acquire 35Pharma Inc., a private, Canada-based clinical-stage biopharmaceutical company. The transaction incorporates HS235, an investigational protein-based therapeutic, into GSK’s pipeline.
HS235 has completed Phase I trials in healthy volunteers, and clinical studies will commence imminently in pulmonary arterial hypertension (PAH) and pulmonary hypertension due to heart failure with preserved ejection fraction (PH-HFpEF).
Pulmonary hypertension (PH) constitutes a progressive, life-shortening condition characterized by elevated blood pressure in the pulmonary arteries. Initial symptoms include breathlessness, fatigue, and chest pain, which advance to heart failure. PH affects approximately 82 million people worldwide across multiple forms, with limited treatment options and a five-year survival rate of about 50%. Analysts forecast the global PH therapeutics market to reach $18 billion by 2032, with activin signaling inhibitors projected to represent 50% of that value.
HS235 targets the activin receptor signaling pathway, a clinically validated mechanism in PH. The molecule demonstrates enhanced selectivity by reducing interactions with BMP9 and BMP10 ligands, which are linked to adverse events such as bleeding and telangiectasia. This profile may mitigate bleeding risks, addressing a critical limitation for patients requiring concomitant anticoagulant or antiplatelet therapy.
Preclinical and early clinical data further indicate potential metabolic benefits, including fat-selective weight loss, preservation of lean mass, improved insulin sensitivity, and favourable modulation of inflammation and adipokines. These attributes hold substantial clinical and commercial relevance given the high prevalence of obesity and insulin resistance among PH patients.
Tony Wood, GSK Chief Scientific Officer, commented: “Pulmonary hypertension affects millions of people worldwide, yet patients remain underserved. We welcome HS235 to our pipeline a potential best-in-class medicine with a differentiated profile that reduces bleeding risk and provides metabolic benefits clinically relevant to PH patients. HS235’s potential protective effects on vascular function, combined with benefits on fat-derived markers of metabolism and inflammation, create new development opportunities within our research, innovation, and investment portfolio to address metabolic, inflammatory, vascular, and fibrotic drivers of chronic diseases affecting the lung, liver, and kidney.”
Ilia Tikhomirov, 35Pharma CEO, added: “Recent advances have transformed our understanding of pulmonary hypertension and its potential reversal. We are pleased to join forces with GSK, a leader in respiratory and inflammatory diseases, to advance HS235’s potential to transform treatment for this debilitating condition.”
Under the agreement terms, GSK will acquire 100% of 35Pharma’s equity for $950 million in cash at closing. The transaction remains subject to customary conditions, including regulatory clearances under the U.S. Hart-Scott-Rodino Act, the Canadian Competition Act, and the Investment Canada Act.
PH encompasses subtypes such as PAH and PH-HFpEF, treated by pulmonologists and cardiologists in specialized academic centers. Globally, PH impacts 82 million individuals; in the U.S., the addressable population for PAH and PH-HFpEF totals approximately 100,000 patients. 35Pharma develops novel TGF-beta superfamily therapeutics, with HS235 as its lead candidate for cardiopulmonary diseases.
Reference
GSK enters agreement to acquire 35Pharma Inc., 25 February 2026, GSK enters agreement to acquire 35Pharma Inc. | GSK
35Pharma to be Acquired by GSK to Accelerate Development of HS235, a Potential Best-in-Class Investigational Medicine for Pulmonary Hypertension (PH), 25 February 2026, https://www.35pharma.com/news/35pharma-to-be-acquired-by-gsk
About Writer
Nikita Chaudhari I BPharm
She is a pharmacy graduate with a keen interest in clinical research, pharmacovigilance, and medical writing, particularly inclined towards publication writing and scientific content development. In her words, she is enthusiastic about scientific documentation and publication writing, aiming to contribute to accurate, ethical, and evidence-based medical communication.