Key clinical point: A switch from adalimumab (ADL), sourced from the European Union (ADL-EU), to ADL biosimilar PF-06410293 (ADL-PF) had no effect on long-term treatment efficacy and safety in patients with active rheumatoid arthritis (RA).
Major finding: The American College of Rheumatology 20 response rate was sustained and similar in patients maintained on ADL-PF and those who switched from ADL-EU to ADL-PF at weeks 26 and 52 (52 weeks: 88.4%, 88.2%, and 87.6%, respectively; 78 weeks: 83.4%, 85.8%, and 84.3%, respectively). From weeks 52-78, the incidence of treatment-related adverse events was 42.6%, 37.0%, and 50.8% for the biosimilar, week 26 switch, and week 52 switch groups, respectively.
Study details: Findings are from an analysis of 597 patients with RA and an inadequate response to methotrexate who continued ADL-PF treatment throughout 78 weeks or switched from ADL-EU to ADL-PF at week 26 or 52 in the phase 3 REFLECTIONS B538-02 trial .
Disclosures: The study was sponsored by Pfizer. Five authors reported being employees and shareholders of Pfizer, and two reported receiving grants/support and consulting fees from several sources.
Source: Fleischmann RM. Arthritis Res Ther. 2021(Sep 25);23:248. doi: 10.1186/s13075-021-02626-4.