Takeuchi T et al. – Abatacept (2 mg/kg and 10 mg/kg) showed a dose–response relationship in Japanese patients with active rheumatoid arthritis (RA) with an inadequate clinical response to methotrexate (MTX). Administration of abatacept in combination with MTX for 24 weeks was well tolerated.Methods
- In this multicenter, placebo–controlled, double–blind, parallel–group, dose–response study, 195 Japanese patients with active RA with an inadequate response to MTX were randomized 1:1:1 to receive 10 mg/kg or 2 mg/kg abatacept plus MTX, or placebo plus MTX, for 24 weeks.
- Abatacept demonstrated a dose–response relationship when given at 2 and 10 mg/kg.
- Based on the American College of Rheumatology criteria (20, 50, and 70 %), the responses to 10 mg/kg abatacept were significantly greater than those to placebo at week 24 (p < 0.001).
- Smaller yet statistically significant responses were also seen in the 2 mg/kg abatacept group.
- Overall rates of adverse events, serious adverse events, and treatment discontinuations because of adverse events were comparable in all three groups.