Radiographic and clinical effects of 10 mg and 25 mg twice-weekly etanercept over 52 weeks in Japanese patients with active rheumatoid arthritis

Objectives: To compare the radiographic and clinical effects of 25 versus 10 mg twice-weekly (BIW) etanercept over 52 weeks in Japanese patients with active rheumatoid arthritis (RA). Methods: This was a post-hoc analysis of a Phase 3 study where Japanese patients with active RA were randomized to receive BIW etanercept 25 mg (n = 182), etanercept 10 mg (n = 192), or methotrexate (n = 176) for 52 weeks (NCT00445770). This analysis included assessments of week-24 and week-52 disease activity, week-52 radiographic progression, and the relationship between baseline characteristics and week 52 clinical outcomes with clinically relevant radiographic progression (CRRP) at week 52. Results: At week 52, there were no significant differences between 25 and 10 mg etanercept in terms of achieving low disease activity or remission. CRRP was observed in 36% and 32% of patients in the 10 and 25 mg groups, respectively. Predictor analysis suggested that worse background disease status, treatment with methotrexate rather than etanercept, and poorer clinical outcomes at week 52 were associated with CRRP. Conclusions: The 25 mg BIW etanercept dosage does not appear to be significantly more efficacious than 10 mg in Japanese patients with RA. Further studies evaluating the optimal etanercept dosing regimen in this patient population may be merited. NCT: NCT00445770.