Comparing the effectiveness and safety of Abatacept and Tocilizumab in elderly patients with rheumatoid arthritis

BACKGROUND: The number of biological DMARDs (bDMARDs) used in elderly patients with rheumatoid arthritis (RA) has increased in recent years. We aimed to compare the drug retention rates and safety of abatacept (ABT) and tocilizumab (TCZ) in elderly patients with RA. METHODS: A total 125 elderly patients with RA (>65 years) who began therapy with either ABT (n = 47) or TCZ (n = 78) between 2014 and 2021 at our institute were enrolled. We compared the drug retention rate and clinical response at 24 weeks between elderly patients with RA treated with ABT and those treated with TCZ. Adverse events (AEs) and the reasons for drug discontinuation were assessed. RESULTS: There was no significant difference in demographic characteristics except for the use of glucocorticoid between the ABT and TCZ groups. There was no significant difference in the drug retention rate between the ABT and TCZ groups. Furthermore, there was no significant difference in the discontinuation rates due to the lack of effectiveness between these two groups. The proportions of the patients archiving low disease activity at 24 weeks did not differ significantly between the two groups. Whereas, the discontinuation rates due to AEs, including interstitial lung disease (ILD), seemed higher in the TCZ group than in the ABT group. In TCZ-treated group, the concomitant use of methotrexate (MTX) significantly increased the incidences of AEs leading to the discontinuation of TCZ. Whereas these was no significant impact of concomitant use of MTX on the incidences of AEs leading to discontinuation in ABT-treated group. CONCLUSIONS: In elderly patients with RA treated with ABT and TCZ, drug retention rates were equivalent between the two groups. There were some differences in safety profiles between ABT and TCZ, and the rates of discontinuation due to AEs, including ILD, seem to be lower with ABT than with TCZ in elderly patients with RA.