A Study of Sotatercept for the Treatment of Pulmonary Arterial Hypertension (MK-7962-003/A011-11)(STELLAR)

The objectives of this study are to evaluate the efficacy and safety of sotatercept (MK-7962) treatment (plus background pulmonary arterial hypertension (PAH) therapy) versus placebo (plus background PAH therapy) at 24 weeks in adults with PAH. The primary hypothesis of the study is that the participants receiving sotatercept will have improved 6-minute walk distance (6MWD) at 24 weeks compared to participants receiving placebo.

This is a Phase 3, randomized, double-blind, placebo-controlled, multicenter, parallel-group study in subjects with symptomatic PAH who present with idiopathic or heritable PAH, PAH associated with connective tissue diseases (CTD), drug or toxin induced, post shunt correction PAH, or PAH presenting at least 1 year following the correction of congenital heart defects (CHDs), and currently on background PAH therapy. The primary efficacy endpoint of the study is exercise capacity, as measured by the 6-minute walk distance (6MWD) measured at 24 week following initiation of treatment. Study duration will be approximately 2 years. A stratified Wilcoxon test will be used for analysis of the primary endpoint, with appropriate imputation for missing data, as detailed in the Statistical Analysis Plan. An unblinded, external, independent Data Monitoring Committee (DMC) will monitor participant safety throughout the course of the study. Participants completing this study will be eligible to receive sotatercept in a separate, open-label extension study.