Merck Announces Phase 3 HYPERION Study of Winrevair Met Primary Endpoint in Recently Diagnosed Adults with Pulmonary Arterial Hypertension

Published: 2025-06-23 07:35:36 ET MRK

Published on 06/23/2025 at 07:35

Merck announced positive topline results from the Phase 3 HYPERION study evaluating WINREVAIR?? (sotatercept-csrk) versus placebo (both in combination with background therapy) in recently diagnosed adults with pulmonary Arterial hypertension (PAH, WHO* Group 1) functional class (FC) II or III at intermediate or high risk of disease progression. HYPERION met its primary endpoint of time to clinical worsening (TTCW) as measured by a composite endpoint of all-cause death, the need for non-planned PAH-related hospitalization > 24 hours, atrial septostomy, lung transplantation, or PAH deterioration.

In HYPERION, WINREVAIR added on top of background therapy (72.2% of patients on double therapy) within 12 months after initial diagnosis of PAH demonstrated a statistically significant and clinically meaningful reduction in the risk of clinical worsening events when compared to placebo. WINREVAIR is the third Phase 3 study of WINREVAIR to demonstrate significant efficacy in adults with PAH. The first was the STELLAR study previously presented at ACC.23, followed by the ZENITH study presented at ACC.25.

In contrast to HYPERION, these safety profile of WINREVAIR was generally consistent with that observed in previous studies. These positive results from HYPERION expand on the body of clinical evidence now including recently diagnosed adults, supporting the practice-changing potential of WINREVAIR in a broad spectrum of PAH patients, including those earlier in their treatment journey. Results from HYPERION will be presented at an upcoming medical meeting later this year and will be submitted to regulatory authorities.

WINREVAIR is currently approved in more than 45 countries based on the results from the STELLAR study. World Health Organization. The HYPERION study (NCT04811092) is a global, double-blind, placebo-controlled clinical trial to evaluate WINREVAIR when added to background PAH therapy in newly diagnosed intermediate or high-risk PAH patients.

Participants who enrolled in the study had a diagnosis of symptomatic PAH (WHO Group 1, classified as FC II [21.3%; 68/320 participants] or III [78.8%; 252/320 participants] within 12 months of study screening. Clinical worsening events are defined as all-cause death, non-planned PAH worsening-related hospitalization of 24 hours, atrial Septostomy, lung transplantization of < 24 hours, and deterioration in six-minute walk test from baseline combined with at least one of the following changes including worsening of WHO FC from baseline, signs/sym symptoms of increased right heart failure, addition of a background PAH therapy or change in the background PAH therapy delivery route to parenteral. Secondary outcome measures were assessed relative to baseline at Week 24: proportion of participants achieving multicomponent improvement (consisting of improvement in 6MWD, improvement in N-terminal pro-B-type natriureticpeptide (NT-proBNP) level and improvement in WHO FC or maintenance of WHO FC II) as well as additional measures.