5‐Methoxypsoralen plus ultraviolet (UV) A is superior to medium‐dose UVA1 in the treatment of severe atopic dermatitis: a randomized crossover trial

Background Ultraviolet (UV) A1 and psoralen plus UVA (PUVA) are effective treatment options for severe atopic dermatitis (AD); however, their relative efficacy has not yet been determined in a head‐to‐head study. Objectives To compare UVA1 and oral 5‐methoxypsoralen (5‐MOP) plus UVA with respect to efficacy, tolerability and duration of response in patients with severe generalized AD. Methods Forty patients were included in this randomized observer‐blinded crossover trial. The patients received either 15 exposures to medium‐dose UVA1 as the first treatment and, in cases of relapse, another 15 exposures to 5‐MOP plus UVA as the second treatment, or vice versa. All patients were followed until 12 months after discontinuation of the last treatment. The SCORAD score was determined by a blinded investigator at baseline, after 10 and 15 treatments each and during the follow‐up period. In addition, all adverse events were recorded during the whole study period. Results Twenty‐three patients completed the crossover treatment. Both phototherapies resulted in clinical improvement; however, PUVA reduced the baseline SCORAD score to a significantly greater extent than UVA1 (mean ± SD 54·3 ± 25·7% vs. 37·7 ± 22·8%; P = 0·041). The median length of remission was 4 weeks (interquartile range 4–12) after UVA1 and 12 weeks (interquartile range 4–26) after PUVA therapy (P = 0·012). Conclusions PUVA provides a better short‐ and long‐term response than medium‐dose UVA1 in patients with severe AD.