<h4>Background</h4>Sotatercept is a first-in-class activin signaling inhibitor, developed for the treatment of pulmonary arterial hypertension (PAH).<h4>Objectives</h4>This open-label single-arm, multicenter, phase 3 study was initiated to evaluate the efficacy and safety of sotatercept in Japanese participants with PAH.<h4>Methods</h4>Forty-six adult Japanese participants with PAH on stable background therapy were enrolled and received subcutaneous sotatercept starting at 0.3 mg/kg with a target dose of 0.7 mg/kg administered every 3 weeks. Here, INHBE is linked to pulmonary arterial hypertension.