Adalimumab (HUMIRA®) is the first fully human anti-TNF monoclonal antibody. This is a multi-center, randomized, double-blind, placebo-controlled study designed to evaluate the inhibition of radiographic progression of adalimumab (ADA) compared to placebo in adult Japanese MTX-naive subjects with early RA. The total treatment period will be up to 52-week (26-week double-blind + 26-week open-label). This is the interim result for 26-weeks double-blind period. Of 334 subjects received the treatment, 171 and 163 subjects were administered ADA 40 mg every other week + MTX 6-8 mg/week (ADA+MTX) and placebo + MTX 6-8 mg/week (MTX), respectively. The mean duration and DAS28-ESR in the both groups of ADA+MTX and MTX were 0.3 years and 6.6, respectively. The linear-extrapolated change of mTSS at Week 26 in ADA+MTX (2.31) showed statistical significance (p<0.001) compared to MTX (4.34). The rates of subjects who had no progression of joint damage were 63.2% in ADA+MTX and 37.9% in MTX at Week 26. The ACR50 and ACR70 response rates at Week 26 for ADA+MTX (64.3% and 47.4%) were significantly superior (p<0.001) compared to MTX (38.7% and 22.7%). The occurrence rates of adverse events were slightly higher in ADA+MTX (80.7%) compared to MTX (71.8%). Overall, the majority of the reported AEs were mild or moderate in intensity and only 1 severe AE in each of ADA+MTX and MTX.