Safety and Immunogenicity of PCV20 in Pediatric Patients With Autoimmune Rheumatic Diseases

ARD patients are at higher risk of pneumococcal infections due to disease-related and therapy-induced immunosuppression. Despite vaccination recommendations, immunogenicity data for PCV20 in ARD pediatric populations are lacking. This prospective phase IV study will enroll 85 patients aged 2-25 years diagnosed with juvenile idiopathic arthritis (JIA), juvenile systemic lupus erythematosus (jSLE), and juvenile dermatomyositis (JDM). All will receive PCV20 per CDC guidance. Blood samples will be collected at baseline (D0), 4 weeks (D28), and 6 months (D180). The functional opsonophagocytic activity (OPA) for specific serotypes will be analyzed. Safety will be monitored through adverse event diaries, clinical evaluations, and disease activity indices. Physical activity will be evaluated by validated questionnaires and via accelerometry.