To assess immunogenicity and safety of the 23-valent polysaccharide pneumococcal vaccine (PPV23) in juvenile idiopathic arthritis (JIA) patients under conventional DMARDs with or without anti-TNF therapy. The influences of demographic data, disease activity and treatment on immune response and the potential deleterious effects of vaccine on disease itself were also evaluated.
17 JIA patients immediately pre-etanercept (Group 1) and 10 JIA patients on stable dose of methotrexate (Group 2) received one dose of PPV23. All patients were evaluated pre-vaccination, 2 months and 12 months post-vaccination for seven pneumoccocal serotypes. Serology was performed by enzyme immunoassay and the immunogenicity endpoints included seroprotection (SP), seroconversion (SP) and geometric mean concentration of antibodies(GMC). Clinical and laboratorial parameters of JIA were evaluated before and after vaccination.
Groups 1 and 2 were comparable regarding age, gender, disease duration and other DMARDs use (p>0.05). Pre-immunization SP and GMC were alike in patients with and without anti-TNF therapy (p>0.05). The frequencies of patients achieving adequate vaccine response (seroconversion in ≥50% of all serotypes) at 2 months (53 vs. 30%, p=0.424) and 12 months (36 vs. 40%, p=1.0) were similar in JIA patients with and without anti-TNF therapy. Further comparison of patients with and without adequate response at 2 months revealed no influence of demographic, clinical and laboratorial JIA parameters (p>0.05). Serious adverse events were not observed.
Anti-TNF therapy in JIA patients does not seem to have an additional deleterious effect on short/long-term PPV23 immunogenicity compared to MTX alone and no influence on disease parameters was observed with this vaccine.