PROFESSOR ANDREW MESSENGER MD FRCP
There are an increasing number of case reports and small case series describing hair regrowth following treatment with the monoclonal antibody drug dupilumab. Dupilumab is licensed for treating atopic dermatitis and the original observations were serendipitous in patients who happened to have alopecia areata as well as dermatitis.
Although there are also some reports of alopecia areata developing during dupilumab treatment for dermatitis most are positive. Dupilumab works by blocking the action of IL-4 and IL-13 which are cytokines involved in an allergic type (Th2) immune response.
Although alopecia areata is typically associated with an autoimmune Th1 cell-mediated reaction there is increasing evidence that Th2 pathways are also involved in the pathology [3], something that might be predicted from the long-recognised association with atopic disease. A group from Mount Sinai hospital in New York has recently published the first randomised controlled trial of dupilumab in 60 patients with extensive alopecia areata [4].
The outcome was a modest improvement in the dupilumab group compared to placebo with 15% recording a 75% reduction in SALT score at 48 weeks. However, of those with a raised IgE level (a feature of atopic disease) 38.5% achieved a SALT75 reduction. The authors suggest that patient selection based on IgE levels may improve results.
REFERENCES 1. Harries M, Macbeth AE, Holmes S, Chiu WS, Gallardo WR, Nijher M, et al. The epidemiology of alopecia areata: a population-based cohort study in UK primary care. Br J Dermatol. 2021 (in press) 2. Sinclair R. Alopecia areata: progress, but who pays? Br J Dermatol. 2021 (in press) 3. Song T, Pavel AB, Wen HC, Malik K, Estrada Y, Gonzalez J, et al. An integrated model of alopecia areata biomarkers highlights both TH1 and TH2 upregulation. J Allergy Clin Immunol. 2018;142(5):1631-4 e13. 4. Guttman-Yassky E, Renert-Yuval Y, Bares J, Chima M, Hawkes JE, Gilleaudeau P, et al. Phase 2a randomized clinical trial of dupilumab (anti-IL-4Ralpha) for alopecia areata patients. Allergy. 2021 (in press)