Methotrexate and azathioprine in severe atopic dermatitis: a 5-year follow up study of a randomised controlled trial

Systemic treatment is indicated for moderate-to-severe atopic dermatitis (AD), refractory to topical treatment. Long-term evidence, up to 5 years, of off-label prescribed methotrexate (MTX) and azathioprine (AZA) is lacking. To investigate long-term effectiveness, safety and drug survival of MTX and AZA. In an open-label follow up phase of a clinical trial patients were seen every 3 months for 5 years. MTX and AZA doses could be in- or decreased concurrent with daily clinical practice. Primary effectiveness outcomes were mean absolute and relative reduction in SCORing Atopic Dermatitis (SCORAD) index and Investigator Global Assessment (IGA) after 5 years compared to baseline. For safety type, frequency, severity and relatedness to treatment of adverse events were investigated. Drug survival was analysed by Kaplan-Meier curves. Thirty-five of 43 originally included patients participated, of which 27 completed follow up. At year 5 mean relative reduction in SCORAD index was similar in MTX and AZA group: 52.8% and 53.8% by descriptive analysis. Eleven serious adverse events occurred in 5 years; for three there was a possible causal relationship. Drug survival demonstrated a longer survival for MTX, but survival in both groups was low after 5 years (MTX n=5, AZA n=1). Based on this relatively small pragmatic study, MTX and AZA seem to be effective and safe as maintenance treatments in moderate-to-severe AD up to 5 years. Few patients in both groups survive on their originally allocated drug although some discontinued due to controlled AD. This article is protected by copyright. All rights reserved