CD19 CAR T-cell therapy for connective tissue disease-associated pulmonary arterial hypertension

<title>Extract</title> Pulmonary arterial hypertension (PAH) is a severe complication of connective tissue diseases (CTDs), including systemic sclerosis (SSc), systemic lupus erythematosus (SLE), primary Sjögren's syndrome (pSS), mixed connective tissue disease, and inflammatory myositis [1]. Patients with CTD-associated PAH exhibit significantly reduced long-term survival compared to those without PAH [2–6]. The refractory nature of underlying CTDs contributes to progressive clinical deterioration and poor outcomes. Current treatments beyond conventional immunosuppression and pulmonary vasodilators remain limited. Emerging evidence implicates B-cell dysregulation in PAH pathogenesis [7, 8]. CD19 chimeric antigen receptor (CAR) T-cell therapy has shown efficacy in refractory CTDs, including SSc and SLE [9, 10]. Herein, we report the first successful application of CD19 CAR T-cell therapy in a patient with CTD-associated PAH.