Objectives: This study aimed to evaluate the safety of CT-P13 in patients with rheumatoid arthritis (RA) during long-term treatment or after switching from innovator infliximab (IFX).
Methods: Patients who completed 54 weeks of treatment in a phase I/II study (PI/II) received CT-P13 at an initial dose of 3 mg/kg at Week 62, with dose increases permitted up to 10 mg/kg. The primary endpoint was adverse event (AE) incidence.
Results: Thirty-four of 38 patients in the maintenance group and 29 of 33 in the switch group reported at least one AE. Safety profiles in both groups were similar to those in PI/II. Eleven of 28 patients who were positive for anti-drug antibodies (ADA) at Week 62 discontinued the study before Week 110. Forty-one of 43 ADA-negative patients remained negative, and 10 of 28 ADA-positive patients became negative during the study. The mean DAS28 (ESR) at Week 134 was 3.166 in the maintenance group and 3.955 in the switch group.
Conclusions: CT-P13 was well tolerated in patients who maintained the treatment after 54 weeks and in patients who switched to CT-P13 after 54 weeks of IFX treatment. The study also demonstrated a stable clinical efficacy of CT-P13 in RA patients.
Keywords: Biosimilar; CT-P13; Infliximab; Long-term safety; Rheumatoid arthritis.