Merck’s Winrevair: Pulmonary arterial hypertension drug shows success ahead of schedule

1. Strong positive interim data from an earlier Phase 3 trial has led to early cessation of Merck’s pulmonary arterial hypertension drug trial.

2. Winrevair is the first activin-signaling inhibitor therapy approved to treat pulmonary arterial hypertension and has shown a favorable safety profile.

The Latest

Merck has announced the early termination of its Phase 3 HYPERION clinical trial for Winrevair following highly promising results that met efficacy endpoints ahead of schedule. Winrevair, a new drug candidate for the treatment of pulmonary arterial hypertension (PAH), has shown significant improvements in key health markers. The decision to halt the study early was based on an earlier phase 3 ZENITH trial that had strong efficacy results for which an independent data monitoring committee had urged Merck to stop the trial early and offer Winrevair to all patients in the study. In the ZENITH trial, the primary outcome measure was time to clinical worsening as measured by first confirmed morbidity or mortality event and secondary outcomes measured improvement in six-minute walk distance, a widely used measure of exercise capacity in PAH patients. The results significantly exceeded expectations, reinforcing the drug’s potential to improve quality of life and mobility for patients with this condition.

Physician’s Perspective

PAH is a rare but severe cardiovascular disorder characterized by increased blood pressure in the lungs due to narrowing of pulmonary arteries. Over time, the condition results in right heart failure and significantly reduces life expectancy. The five-year mortality rate for patients with PAH is approximately 43%. Common symptoms include shortness of breath, dizziness, and fatigue, all of which progressively worsen without effective intervention. Current treatments focus on symptom management, but many patients still experience declining function over time. Winrevair presents a breakthrough in PAH management by targeting key molecular pathways that regulate blood vessel remodeling and pulmonary artery narrowing. Physicians have responded positively to the trial results, emphasizing the potential of Winrevair to not only improve symptoms but also modify disease progression in PAH patients. If approved, it would provide a much-needed alternative for patients with limited treatment options.

Molecular Target of Therapy

Winrevair is an activin-signaling inhibitor. This is a key signaling pathway involved in the growth and remodeling of blood vessels. Derangements in this pathway are implicated in PAH. By blocking this signaling pathway, Winrevair promotes dilation of blood vessels, leading to a reduction in pulmonary artery pressures.

Company History

Merck, a global pharmaceutical leader, has a long-standing commitment to developing innovative therapies across various therapeutic areas. The company has made significant strides in cardiovascular and pulmonary medicine, with a strong focus on unmet medical needs. Winrevair is was developed through Merck’s extensive research and development efforts, aimed at addressing the complex nature of PAH. Merck continues to lead in the oncology market with Keytruda and has a strong presence in the vaccine therapeutic area with Gardasil.

Additional Reading: https://pubmed.ncbi.nlm.nih.gov/36877098/