Bio-Thera Solutions and Biogen have announced the publication of Phase 3 clinical trial results in Arthritis Research & Therapy, demonstrating the sustained efficacy and safety of TOFIDENCE™ (BAT1806/BIIB800), a biosimilar to tocilizumab, in patients with rheumatoid arthritis (RA). The study evaluated the impact of switching from reference tocilizumab to TOFIDENCE.
The Phase 3 study was a multicenter, multiregional, double-blind, active-controlled clinical equivalence study. Participants with active RA, despite methotrexate treatment, were randomized to receive either reference tocilizumab (TCZ) for 48 weeks, TCZ for 24 weeks followed by BAT1806/BIIB800 for 24 weeks, or BAT1806/BIIB800 for 48 weeks.
Key Findings from Treatment Period 2 (Weeks 24-48)
Results from Treatment Period 2 (TP2) of the Phase 3 study demonstrated maintenance of comparable clinical efficacy, safety, immunogenicity, and pharmacokinetics (PK) following switch to BAT1806/BIIB800 from TCZ in patients with RA and an inadequate response to methotrexate.
Of the 621 randomized participants, 577 (92.9%) completed Treatment Period 1 (TP1, Week 0-24) and entered TP2 (TCZ: N = 145 [93.5%]; TCZ to BAT1806/BIIB800: N = 142 [92.2%]; BAT1806/BIIB800: N = 290 [92.9%]). Proportions of ACR20 responders were similar between treatment groups throughout TP2 (87.8%, 90.3%, and 90.4%, respectively, at week 48), as were proportions of ACR50 and ACR70 responders, and reduction in DAS28. Drug trough levels and antidrug antibody incidences were comparable between the treatment groups. Adverse events were balanced across the treatment groups and no fatal events were reported.
Clinical Implications
"We are pleased to publish the switching data of TOFIDENCE (BAT1806/BIIB800) from reference tocilizumab that strongly supports its biosimilarity to tocilizumab for a long-term period in treating patients with active rheumatoid arthritis and an inadequate response to MTX," said Dr. Xiaolei Yang, Executive Medical Director for Rheumatology and Immunology at Bio-Thera. "We hope the study results help allay any concerns over safety and efficacy of TOFIDENCE (BAT1806/BIIB800) for use in patients who were previously treated with reference product."
These longer-term findings reinforce the results reported for TP1 and further support biosimilarity. The data suggest that switching from reference tocilizumab to TOFIDENCE does not compromise efficacy or safety in RA patients who have been stabilized on the original biologic.
