23-valent Polysaccharide Pneumococcal Vaccine in Juvenile Idiopathic Arthritis Patients Under Anti-TNF Therapy

Objectives: To assess immunogenicity and safety of the 23-valent polysaccharide pneumococcal vaccine (PPV23) in JIA patients with and without anti-TNF therapy. The influences of demographic data, disease activity and treatment on immune response and the potential deleterious effect of vaccine on disease itself were also evaluated. Methods: 17 JIA patients immediately pre-etanercept (Group 1) and 10 JIA patients on stable dose of methotrexate (Group 2) will receive one dose of PPV23. All patients will be evaluated pre-vaccination, 2 months and 12 months post-vaccination for seven pneumoccocal serotypes. Serology will be performed by enzyme immunoassay and the immunogenicity endpoints will include seroprotection (SP), seroconversion (SP) and geometric mean concentration of antibodies (GMC). Clinical and laboratorial parameters of JIA will be evaluated before and after vaccination.