A Long-Term Follow-Up Study of Sotatercept for Treatment of Pulmonary Arterial Hypertension: Interim Results of SOTERIA.

BACKGROUND

SOTERIA (NCT04796337) is an ongoing open-label study evaluating long-term safety, tolerability, and efficacy of sotatercept in participants with pulmonary arterial hypertension (PAH).

METHODS

Eligible adults with PAH on stable background therapy who completed a prior sotatercept study without early discontinuation were enrolled. Participants received subcutaneous sotatercept (≤0.7 mg·kg Q3W). Safety and tolerability (primary objective) were assessed by adverse events (AEs), vital signs, and laboratory assessments. Efficacy (secondary objective) was assessed by 6-minute walk distance (6MWD), N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, WHO functional class (FC), clinical worsening events, and simplified French risk score (SFRS). The data cutoff date was 08NOV2023.

RESULTS

Altogether, 426 participants were included in the analyses. Mean (sd) duration of exposure to sotatercept and follow-up in SOTERIA was 448.6 (172.93) days (range 21-923 days; 523 patient-years). Of 426 participants, 387 (90.8%) experienced AEs, 15 (3.5%) discontinued treatment, 129 (30.3%) had serious AEs, and 11 (2.6%) had serious AEs related to treatment. There were 12 deaths (2.8%). Among AEs of interest, epistaxis (22.1%) and telangiectasia (16.9%) were the most frequently reported individual events. Twenty-two (5.2%) participants had serious bleeding events, including 2 (0.5%) with serious bleeding leading to death (not related to treatment by investigator judgment). Improvements in 6MWD, NT-proBNP, WHO FC, and SFRS achieved from baseline of SOTERIA were largely maintained at one year, including in the placebo-crossed group.

CONCLUSION

Interim results of SOTERIA support the favorable benefit-risk of add-on sotatercept treatment in adults with PAH. Follow-up reports from this study will provide additional information on benefit/risk.