But other, less stringent measures of disease activity showed fairly good maintenance with methotrexate monotherapy. For example, the percentage of patients at 78 weeks with low disease activity based on a DAS28-CRP score of less than 3.2 was 81% in the methotrexate monotherapy group and 91% among the patients on both active drugs. Of the patients on methotrexate alone, 84% had an SDAI (Simplified Disease Activity Index) of 11 or less at 78 weeks, as did 92% of those on methotrexate plus adalimumab. There was no radiographic progression in 81% of the patients in the monotherapy arm at 78 weeks and in 89% of the patients on both drugs. An ACR 50 (American College of Rheumatology scale showing a 50% improvement) response was recorded at 78 weeks in 80% of patients on methotrexate only and in 89% of patients on methotrexate plus adalimumab.
"On the whole, patients on methotrexate [monotherapy] did extremely well and maintained their responses," Dr. Emery said. These are "the first global, randomized, controlled data on discontinuation of a TNF inhibitor after successful achievement of stable, low disease activity. The data suggest that for a large proportion of very early RA patients, a 26-week course of adalimumab and methotrexate, followed by 52 weeks of methotrexate monotherapy, may be a viable option to allow for the achievement of good outcomes."
The study is funded by Abbott, the company that markets adalimumab (Humira). Dr. Emery said that he has received research support from and has been a consultant to Abbott, Bristol-Myers Squibb, Merck, Pfizer, and Roche.