Impact of Janus kinase inhibitors on antibody response to 13-valent pneumococcal conjugate vaccine in patients with rheumatoid arthritis

Objectives To evaluate the antibody response to 13-valent pneumococcal conjugate vaccine (PCV13) in patients with rheumatoid arthritis receiving Janus kinase inhibitors (JAKIs). Methods Fifty-three patients receiving methotrexate (MTX; n = 10), JAKI (n = 20), or MTX + JAKI (n = 23) were vaccinated with PCV13. Serum concentrations of immunoglobulin G (IgG) antibodies to 13 pneumococcal serotype capsular polysaccharides were quantified before and 4-6 weeks after vaccination. Positive antibody response was defined as a 2-fold or more increase in IgG concentrations from prevaccination levels. Results After vaccination, IgG concentrations significantly increased in all treatment groups (P <0.001), but fold increases (postvaccination to prevaccination ratios) were different among treatment groups (9.30 for MTX, 6.36 for JAKI, and 3.46 for combination therapy). Positive antibody response rates were comparable between the MTX group (90%) and the JAKI group (95%) but lower in the MTX + JAKI group (52.2%). In a multivariable logistic regression analysis, the combination therapy was the only factor associated with a reduced antibody response to PCV13. No severe adverse events were observed in any treatment group. Conclusion Although JAKIs do not impair PCV13 immunogenicity in rheumatoid arthritis patients, the combination of MTX with JAKI can reduce the antibody response in this patient population.