Dupilumab, targeting the interleukin-4α receptor and inhibiting the action of interleukin-4 and interleukin-13, was recently approved for treatment of moderate to severe atopic dermatitis. There is limited data on long-term effects and safety among patients with severe atopic dermatitis treated with dupilumab. Weight gain was observed among patients treated with dupilumab in our clinic. The aim was to describe weight change in a cohort study of patients with severe atopic dermatitis treated with dupilumab from baseline to follow-up after 12 months, and to analyze if weight change was associated with effect of treatment, reported appetite, and/or disturbed night sleep due to itching.

All patients with atopic dermatitis receiving systemic treatment at the Unit of Dermatology, Karolinska University Hospital, have been registered and monitored consecutively since January 2017. This cohort constituted all patients who started treatment on dupilumab or methotrexate between 10 January 2017 and 30 June 2019 with at least 6 months of follow-up within the study period. The following variables were monitored at start of and during treatment: Eczema Severity Score Index, Patient-Oriented Eczema Measure, visual analogue scale for pruritus 10 cm, Montgomery-Åsberg Depression Rating Scale, Dermatology Life Quality Index, and weight. Data analyses were performed using two-sample Wilcoxon-Mann-Whitney rank-sum test, or the Wilcoxon matched-pairs sign-rank test with a p-value < 0.05 considered as statistically significant.

Patients treated with dupilumab (n = 12) gained weight (mean 6.1 kg, range [0.1–18.0], p = 0.002) after 1 year on treatment. The majority of patients showed a good response to treatment with dupilumab (n = 11); at follow-up at 6, 9, or 12 months, they reached EASI-90 (n = 6), EASI-75 (n = 4), or EASI-50 (n = 1). There was no significant association between weight gain and treatment response, reported appetite, or disturbed night-sleep due to itch. Patients treated with methotrexate showed no significant weight change (n = 8).

To our knowledge, this is the first report on a possible association between weight gain and dupilumab treatment; the extent of the association is yet to be seen, as is the mechanism behind this finding.