Long-term efficacy and safety of certolizumab pegol in Japanese rheumatoid arthritis patients who could not receive methotrexate: 52-week results from an open-label extension of the HIKARI study

Objectives. To evaluate the long-term efficacy and safety of certolizumab pegol (CZP) treatment and to assess the efficacy of two CZP maintenance dosing schedules in Japanese rheumatoid arthritis (RA) patients who could not receive methotrexate (MTX). Methods. HIKARI double-blind (DB) patients were entered into an open-label extension (OLE) study. Patients withdrawn at 16 weeks due to lack of efficacy and DB completers without a 24-week American College of Rheumatology (ACR) 20 response received CZP 200 mg every 2 weeks (Q2W). DB completers with 24-week ACR20 responses were randomized to CZP 200 mg Q2W or CZP 400 mg every 4 weeks. Results. The ACR20/ACR50/ACR70 response rates of DB completers (n=98) were 82.7%/56.1%/34.7% at OLE entry, and 83.7%/65.3%/48.0% at 52 weeks, respectively. Other clinical, functional, and radiographic outcomes were sustained during long-term administration of CZP, even without MTX. No new unexpected adverse events were observed during long-term CZP treatment. The efficacy and safety of CZP treatment were similar between the two dosing schedules. Conclusions. Long-term CZP administration is efficacious and safe for RA patients. No obvious differences in clinical efficacy and safety were observed between the two dosing schedules. The choice between two maintenace regimens adds flexibility in administration schedules for RA patients and physicians.