Merck's Winrevair approved by EC for adult pulmonary hypertension

Merck & Co, known as MSD outside the US and Canada, has gained European Commission (EC) approval for its pulmonary arterial hypertension (PAH) therapy, Winrevair (sotatercept). This authorization allows the drug to be used in combination with other PAH therapies to enhance exercise capacity in adults classified under World Health Organization (WHO) functional classes two and three.

PAH is a severe condition impacting around 30,000 individuals in the EU. It is characterized by the thickening and narrowing of blood vessels in the lungs, which obstructs blood flow, increases blood pressure, and places considerable strain on the heart. Winrevair, administered as a single injection every three weeks, stands out as the first activin signaling inhibitor therapy for PAH approved across all 27 EU member states, Iceland, Liechtenstein, and Norway.

The EC's decision came after a recommendation from the European Medicines Agency's (EMA) human medicines committee. The approval was bolstered by positive results from the phase 3 STELLAR trial. This trial compared Winrevair to a placebo, both used alongside standard care therapies in PAH patients. The combination therapy with Winrevair yielded statistically significant and clinically meaningful improvements in the primary endpoint, which was the six-minute walk distance. Additionally, it showed benefits in multiple secondary outcomes, including reducing the risk of death or clinical worsening.

Joerg Koglin, senior vice president and head of general medicine, global clinical development at Merck Research Laboratories, highlighted the significance of this approval. He noted that Winrevair is the first therapy to target the activin signaling pathway, expressing pride in offering this innovative treatment to more patients. He emphasized Merck's commitment to further exploring Winrevair's potential in addressing unmet needs in PAH management.

The EC's approval follows a similar authorization by the US Food and Drug Administration (FDA) five months earlier, also for treating PAH in adults. Merck acquired access to Winrevair through its $11.5 billion acquisition of Acceleron Pharma in 2021. At the time of the acquisition, Merck's chairman and CEO, Rob Davis, remarked on Acceleron's innovative research, which produced this promising late-stage candidate. He emphasized that Winrevair complements and strengthens Merck's cardiovascular portfolio and pipeline, building on the company's legacy in cardiovascular disease treatment.