Adalimumab with Methotrexate vs. Adalimumab Monotherapy in Psoriasis: First-Year Results of a Single-Blind Randomized Controlled Trial

Abstract

Adalimumab is normally prescribed with methotrexate (MTX) in rheumatoid arthritis given the enhanced treatment effect and reduced antidrug antibody formation compared with adalimumab monotherapy (ADL). In psoriasis, the long-term treatment effects and pharmacokinetic profile have not been investigated extensively. We conducted a randomized controlled trial to assess the efficacy, safety, pharmacokinetics, and immunogenicity of adalimumab combined with MTX 10 mg per week (ADL-MTX group) compared with that of ADL (ADL group) in chronic plaque psoriasis. A total of 31 patients in the ADL-MTX group and 30 in the ADL group were analyzed. After 1 year, a (nonsignificant) better drug survival was found in the ADL-MTX group (74.2 vs. 58.6%, P= 0.15). The PASI 75 response in week 49 was 58.1 versus 36.7% (P= 0.13), and the median (interquartile range) serum-trough concentrations were 6.8 (5.5‒9.2) versus 5.9 (3.5‒8.8) mg/l (P= 0.26) in the ADL-MTX group and ADL group, respectively. Fewer patients showed antidrug antibodies in the ADL-MTX group (22.6 vs. 60.0%, P < 0.01). No serious adverse events occurred. Combination therapy of adalimumab and MTX results in fewer patients showing antidrug antibodies, with a trend toward a better PASI 75 response, drug survival, and higher serum-trough concentrations than ADL. Patient-reported outcomes and adverse events were comparable between the groups.