Comparative efficacy and safety of tumor necrosis factor inhibitors and their biosimilars in patients with rheumatoid arthritis having an insufficient response to methotrexate A network meta-analysis

Objective This study aimed to compare the effectiveness and safety of tumor necrosis factor inhibitor (TNFI) biosimilars to TNFI originators in patients with active rheumatoid arthritis (RA) who responded inadequately to methotrexate (MTX). Methods We conducted a meta-analysis of randomized controlled trials (RCTs) to compare the effectiveness and safety of TNFI biosimilars to TNFIs in patients with RA who had not responded adequately to MTX. Results A total of 18 RCTs (8 adalimumab, 7 infliximab, and 3 etanercept) comprising 4039 patients randomized to TNFI biosimilars and 3905 to TNFI treatment were included. The American College of Rheumatology 20% improvement (ACR20) response rate was significantly higher for TNFI biosimilar-treated patients than for TNFI-treated patients (odds ratio, OR 1.140, 95% confidence interval, CI 1.031-1.261, P = 0.011); however, subgroup analysis by the TNFI type showed that the ACR20 response rates were not different among the biosimilars of adalimumab, infliximab, and etanercept compared with the originators. The ACR50 response rate was significantly higher for TNFI biosimilar-treated patients than for TNFI treated patients (OR 1.096, 95% CI 1.001-1.200, P = 0.047). Subgroup analysis by the TNFI type showed that the ACR50 response rates did not differ among the biosimilars of adalimumab and infliximab compared with the originators; however, the ACR50 response rate was significantly higher in etanercept biosimilar-treated patients than in etanercept-treated patients (OR 1.406, 95% CI 1.111-1.780, P = 0.005). No significant difference was observed between the TNFI biosimilars and TNFIs as per ACR70. There was no significant difference in the number of patients who experienced adverse events (AEs) between TNFI biosimilars and TNFIs (OR 0.961, 95% CI 0.876-1.055, P = 0.402); however, subgroup analysis by the TNFI type showed that the adalimumab biosimilar caused fewer AEs than adalimumab (OR 0.865, 95% CI 0.756-0.989, P = 0.034). Serious AEs and withdrawals due to AEs did not differ between TNFI biosimilars and TNFIs. Conclusion This meta-analysis showed that TNFI biosimilars had an overall comparable efficacy and safety profile compared with their originators in RA patients.