Safety of sarilumab in a Japanese population with rheumatoid arthritis by age group: Data from an interim analysis of a postmarketing surveillance study.

Objectives: Using data from a postmarketing surveillance, this interim subgroup analysis investigated the safety of sarilumab in younger (<65 years) and older patients (≥65 and ≥75 years) with rheumatoid arthritis.

Methods: During this interim analysis, patients who were treated with sarilumab in Japan were enrolled between June 2018 and 2021. Data collected by 12 January 2022 were analysed, with adverse drug events monitored over 52 weeks.

Results: Of 972 patients with available data, the proportion of patients aged <65 years, ≥65 years, and ≥75 years was 40.8%, 59.2%, and 27.8%, respectively. Most patients (95.5%) received the standard 200 mg dose of sarilumab as the initial dose. Adverse drug reactions were reported in 24.6% of patients, with serious events accounting for 6.4% of cases. No malignancy and low incidences of adverse drug reactions of special interest were reported across all age groups (<65 years, 7.8%; ≥65 years, 8.2%; ≥75 years, 8.5%). When stratified by absolute neutrophil count above and below the lower limit of normal, there were no numerical differences in incidences of serious and non-serious infections between age groups.

Conclusions: Regardless of age, sarilumab therapy was well tolerated by patients with rheumatoid arthritis, with no new safety signals reported in this study.