Efficacy of Pneumococcal Polysaccharide Conjugate Vaccine (13-valent, Adsorbed) in Patients with Systemic Juvenile Idiopathic Arthritis Treated with Genetically Engineered Biologic Drugs (Tocilizumab or Canakinumab): Prospective Cohort Study

Background. Immunological potency of 13-valent pneumococcal vaccine (PCV-13) in children with systemic juvenile idiopathic arthritis (SJIA) is still unstudied. Estimates of the genetically engineered biologic drugs (GEBD) effects on pneumococcal vaccination results also remain controversial.Objective. The aim of the study was to explore the PCV-13 efficacy in patients with SJIA and who is on treatment with monoclonal antibodies against interleukin 6 receptor (tocilizumab) and interleukin 8 receptor beta (canakinumab).Methods. The study included patients under the age of 18 with SJIA in remission or active form of disease vaccinated with PCV-13. The vaccine was administered in single dose of 0.5 ml intramuscularly in patients on treatment with GEBD or 3 weeks before GEBD administration for the first time (for patients with active disease). Vaccination was considered effective at achievement of the minimum protective level of antibodies to capsular polysaccharide of pneumococcus (anti-SPP IgG; ≥ 7 U/ml) or increase of anti-SPP IgG level ≥ 2 times in 4 weeks after vaccination. The anti-SPP IgG levels were measured with enzyme immunoassay.Results. The study included 53 patients (27 girls) in remission of SJIA and 25 (16 girls) in active disease. Median age was 13.3 and 10.8 years respectively. Tocilizumab/canakinumab was administrated in 43/10 and 18/7 patients respectively. Minimum significant anti-SPP IgG level and two-fold increase in anti-SPP IgG level were recorded in 49/53 (92%) and 32/53 (60%) patients with SJIA in remission, as well as in 22/25 (88%) and 18/25 (72%) patients in active disease respectively. PCV-13 immunological potency in patients with SJIA in remission and in active disease (in those who were initially administrated and who did not receive GEBD) did not differ.Conclusion. PCV-13 vaccination allows to achieve protective antibodies level in most of the patients with SJIA in children population regardless of the disease stage and the history of GEBD administration.