Belimumab combined with standard therapy significantly improved right ventricular function in SLE-associated pulmonary arterial hypertension.
Background
Pulmonary arterial hypertension (PAH) is a severe, progressive complication of Systemic Lupus Erythematosus (SLE), leading to increased pulmonary vascular resistance and right ventricular failure. Current standard-of-care often falls short, with many patients experiencing poor prognosis despite targeted therapies. Given the autoimmune nature of SLE, therapies that modulate the immune system, such as B-cell targeted agents like belimumab, are being explored to address the underlying inflammatory drivers of SLE-PAH and improve cardiac outcomes.
Study Design
This ambispective cohort study investigated 10 patients with SLE-PAH treated with intravenous belimumab (10 mg/kg). This group was compared against 30 matched SLE-PAH controls receiving conventional immunosuppression without biologics. All patients received either dual or triple combination targeted therapy for PAH. Patients were followed for 12 months, with clinical, laboratory, and echocardiographic parameters, including SLE Disease Activity Index 2000 and PAH risk stratification, compared between groups.
Results
Belimumab-treated patients demonstrated rapid and sustained improvements across multiple parameters. These included reductions in N-terminal pro-B-type natriuretic peptide (NT-proBNP), improved WHO functional class (WHO-FC), increased 6-minute walking distance, and lower soluble suppression of tumorigenicity 2 (sST2) levels. Significant improvements were also observed in echocardiographic markers of right ventricular function and structure, specifically the ratio of tricuspid annular plane systolic excursion to pulmonary artery systolic pressure (TAPSE/PASP) and right ventricular end-diastolic basal dimension (RVDd).
Key Findings
- Belimumab-treated SLE-PAH patients showed rapid and sustained improvements in
NT-proBNP,WHO-FC, and6-minute walking distance. - Significant improvements were observed in
TAPSE/PASPandRVDdin the belimumab group compared to controls at 12 months. - All 10 belimumab-treated patients were stratified into the low-risk category at 12 months.
- In the control group, 1 patient remained intermediate-low risk and 4 patients were intermediate-high risk at 12 months.
Why It Matters
This study suggests that belimumab could be a valuable add-on therapy for SLE-PAH, potentially improving right ventricular function and overall risk stratification. For individuals with SLE-PAH, this offers a new therapeutic avenue beyond conventional immunosuppression, targeting the underlying autoimmune pathology. While this was a single-center study, the observed improvements in critical cardiac and functional parameters indicate a promising path for clinical translation, potentially leading to better long-term outcomes and a shift towards lower risk categories for these patients.
belimumab
sle-pah
pulmonary-hypertension
autoimmune
b-cell-modulator
cohort-study