Adalimumab vs adalimumab + methotrexate in psoriasis: First-year results on effectiveness, drug survival, safety, and immunogenicity

Dr Gayle van der Kraaij (Amsterdam UMC, the Netherlands) presented the first-year results from a Dutch/Belgian study that showed increased efficacy, adalimumab serum levels, and fewer antidrug antibodies when adalimumab is supplemented with methotrexate [1].

She explained the problem: adalimumab therapy is hampered by primary and secondary non-response. The lack of response is because in many patients only low serum drug levels can be detected, which is directly attributable to the formation of antidrug antibodies. The researchers sought to optimise adalimumab efficacy by applying a trick learned from rheumatoid arthritis, namely that the addition of methotrexate can alleviate this problem. The investigators performed a pragmatic randomised controlled trial in psoriasis patients, which was assessor-blinded in 5 hospitals in the Netherlands and Belgium. They compared adalimumab (n=30) vs adalimumab with methotrexate (10 mg/week supplemented with folic acid; n=31). All patients were eligible for adalimumab therapy according to the guidelines (PASI >8) and were adalimumab naïve. There will be follow-up every 12 weeks for 3 years, but because the trial is still ongoing, this presentation presented the key results for the first year.

Looking at the efficacy, significantly more patients in the combination arm reach PASI-75 at week 49 on adalimumab + methotrexate (58%) vs 31% in the monotherapy group (P=0.04). With regard to drug survival, patients on the combination arm have a slightly better drug survival at week 49, with 59% adalimumab vs 74% adalimumab + methotrexate; although these data are not statistically significant at this time point (P=0.26). Thirdly, the serum trough levels were significantly higher in the combination arm at about 6 mg/L (vs about 3.5 mg/L in patients treated with adalimumab alone). Lastly, antidrug antibody formation after a year was 47% in the adalimumab group vs 16% in the adalimumab + methotrexate (P=0.01).

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   1. Van der Kraaij G. P018, SPIN 2019, 25-27 April, Paris, France.

Posted on 21 June, 201924 March, 2021