A Cochrane review ¹ on the human anti-TNFalpha monoclonal antibody adalimumab in the treatment of rheumatoid arthritis (RA) included six studies with a total of 2381 subjects.

With adalimumab 40 mg s.c. every other week + methotrexate (or DMARDs, disease-modifying anti-rheumatic drugs), the RRs to achieve an American College of Rheumatology (ACR) criteria response 20, 50, and 70 at 52 weeks as compared to placebo were 2.46 (95%CI 1.87 to 3.22), 4.37 (95% CI 2.77 to 6.91), and 5.15 (95% CI 2.60 to 10.22), with NNTs of 2.9, 3.1, and 5.3, respectively. At 52 weeks, adalimumab 40 mg e.o.w. and 20 mg every week (e.w.) significantly slowed the radiological progression, erosion score, and joint space score (only with 40 mg e.o.w.).

Adalimumab in monotherapy is also efficacious but the effect size is lower than with combined therapy. With adalimumab 40 mg s.c. every other week as monotherapy versus placebo, the RRs to achieve an ACR 20, 50, and 70 response at 24/26 weeks were 1.91 (95% CI 1.17 to 3.10), 2.84 (95% CI 1.58 to 5.12), and 7.33 (95% CI 2.25 to 33.90) with NNTs of 5.0 (95% CI 3.0 to 9.0), 7.0 (95% CI 4.0 to 20.0), and 9.0 (95% CI 3.0 to 38.0), respectively.

In most of the analysed studies and comparisons, there were not significant differences in safety outcomes between adalimumab and control groups.