This single-center retrospective case series assessed the early clinical effects of adding sotatercept to stable background therapy in patients with pulmonary arterial hypertension (PAH) treated at Ruijin Hainan Hospital, Shanghai Jiao Tong University School of Medicine. Consecutive patients who received sotatercept between May and December 2025 were included. The analysis focused on short-term efficacy measures—exercise capacity, cardiac biomarkers, and echocardiographic estimates of pulmonary artery pressure—and on hematologic safety signals.
Seven adult PAH patients received sotatercept during the enrollment period. One patient discontinued after a single dose for personal reasons and was excluded from subsequent efficacy analyses. The remaining six patients completed a 1-month follow-up; three of those completed a 3-month follow-up. Sotatercept was administered in addition to each patient’s preexisting, stable background PAH therapy. The report is a retrospective case series from a single center and does not describe a randomized or controlled protocol.
The primary functional efficacy measure reported was change in 6-minute walk distance (6MWD). At the 1-month follow-up, five of six analyzed patients demonstrated a significant improvement in 6MWD compared with baseline. Among the three patients with 3-month data, two showed further improvement in 6MWD at that time point.
World Health Organization functional class (WHO FC) was reported for those with later follow-up: at 3 months, WHO FC improved in two of three patients. The authors highlight short-term gains in exercise tolerance and functional status among treated patients, while noting limited sample sizes for longer follow-up.
Biomarker response was assessed using NT-proBNP. At 1 month, NT-proBNP was substantially reduced compared with baseline in five of six patients. Among the three patients with 3-month follow-up, one showed further reduction of NT-proBNP at 3 months.
Echocardiographic estimates of systolic pulmonary artery pressure (PASP) were reported for the three patients with 3-month data: two of those three patients had decreased echocardiographic PASP at 3 months compared with baseline. These early hemodynamic and biomarker changes were presented as concordant with observed functional improvements, but objective hemodynamic data from right-heart catheterization were not reported in the abstract.
Core safety monitoring centered on hematologic parameters. Among the six patients in the efficacy analysis, one experienced an excessive increase in hemoglobin (Hgb) that led to a delayed sotatercept dose. One patient developed a decrease in platelet count (PLT). No other adverse reactions were reported in the cohort. The authors describe the safety profile as manageable in the short term but emphasize the need for ongoing monitoring of Hgb and platelets during sotatercept therapy.
The investigators conclude that, in this small Chinese cohort, sotatercept produced significant short-term improvements in cardiac function markers and exercise capacity with an acceptable and controllable safety profile. They explicitly acknowledge important limitations: the small sample size (seven treated, six included in efficacy analyses), short follow-up duration (1 month for all six; 3 months for three), retrospective single-center design, and the absence of controlled comparators. These constraints limit the generalizability and strength of causal inference.
This case series provides early, real-world observations of sotatercept use in Chinese PAH patients when added to background therapy, highlighting improvements in 6MWD, reductions in NT-proBNP, and decreases in echocardiographic PASP in some patients, alongside hematologic side effects that required dose management in isolated cases. The findings support the potential of sotatercept to improve short-term clinical and laboratory endpoints in PAH but do not replace evidence from larger, randomized, long-term studies. The authors recommend verification of these early signals through large-scale, prospective trials with systematic hemodynamic assessment and longer safety follow-up.
Conflicts of interest
All authors declared no conflicts of interest in the source report.
Notes on data completeness
The abstract reports key results as counts of patients with improvement or adverse events but does not provide individual patient-level numeric values, mean changes, statistical tests, or right-heart catheterization hemodynamic data in the abstract text. Those details were not reported in the PubMed abstract and would need to be sought in the full text for more granular analysis.