Safety and immunogenicity of the recombinant zoster vaccine in patients with rheumatoid arthritis using abatacept: a pilot multicentre, double-blind, randomised controlled trial

OBJECTIVES: The objective of the study is to evaluate the safety and immunogenicity of the recombinant zoster vaccine (RZV) in patients with rheumatoid arthritis (RA) using abatacept. METHODS: We randomised 70 participants to receive 2 doses of RZV or placebo 8 weeks apart. The primary immunologic endpoint was the proportion of participants developing a ≥4-fold increase in anti-glycoprotein E (gE) immunoglobulin (Ig)G antibodies (humoral responders) and those developing a ≥2-fold increase in interferon gamma (IFN-γ)+ or interleukin-2 (IL-2)+ gE-specific spot-forming cells (cellular responders), at week 12 (ie, 4 weeks post-second RZV dose). The secondary immunologic endpoint was the geometric mean fold rise (GMFR) in cellular and humoral vaccine responses. For safety, we solicited adverse events following each dose, serious adverse events (SAEs) during the 52-week study period, and evaluated the potential for RA flares by assessing pre- and postvaccination Disease activity score-28 for rheumatoid arthritis with erythrocyte sedimentation rate, Clinical Disease Activity Index (CDAI), and Outcome Measures in Rheumatology (OMERACT) rheumatoid arthritis flare questionnaire (RA-FQ) scores. RESULTS: Fifty-six (75%) participants received RZV, and 14 (25%) received a placebo. Among those receiving RZV, only 22 (42.3%) of participants surpassed the 4-fold threshold for humoral response, and anti-gE IgG GMFR at week 12 was 4.55 (3.16, 6.47). Only 5 (10.2%) patients with RZV mounted cellular responses. Six SAEs were noted, and the proportion of patients with RA flare was similar between RZV and placebo groups (38 [68%] vs 9 [64%]). CONCLUSIONS: Our data suggest that RZV is safe in patients with RA using abatacept, but that the vaccine response is attenuated in such patients. Further studies should be undertaken to evaluate whether holding abatacept around the time of vaccination would improve vaccine response.