Dupilumab-induced skin-associated side effects in patients with chronic rhinosinusitis with nasal polyposis.

Chronic rhinosinusitis with nasal polyposis (CRSwNP) is a typical type-2 inflammation involving T-helper type-2 cells and impairing quality of life due to nasal obstruction, discharge and reduced sense of smell. Recently, the anti-IL4Rα antibody dupilumab was approved for CRSwNP. While dermatologic side effects in patients treated with dupilumab for atopic dermatitis are frequently observed, there is limited knowledge about these effects in patients with CRSwNP. We aimed to investigate frequency and characteristics of dermatologic side effects following initiation of dupilumab treatment in a cohort of Austrian CRSwNP patients. Therefore, CRSwNP patients presenting at the Department of Otorhinolaryngology, Head and Neck Surgery at the Vienna General Hospital were retrospectively evaluated for newly developed skin eruptions while under dupilumab treatment. Incidence was calculated and details on clinical symptoms were collected. One hundred and ninety-two CRSwNP patients receiving dupilumab treatment were included, comprising a cumulative follow-up of 89.65 years (median: 5.5, IQR: 5.9). We observed dermatologic side effects in four patients starting at a median time of 15.5 (range 4-23) weeks after dupilumab initiation corresponding to an incidence-rate of 4.46 (95%-confidence interval 1.39-11.23) events per 100 patient-years follow-up. The majority (75%, 3/4) of affected patients developed psoriasis-like dermatitis, whereas one individual experienced rosacea-like folliculitis and alopecia areata. While dupilumab dosing was reduced in 3/4 CRSwNP patients, one patient completely stopped dupilumab therapy. Our study provides the first comprehensive evaluation of both frequency and characteristics of dermatologic side effects caused by dupilumab in CRSwNP patients. All affected patients developed Th1-inflammatory associated skin disorders - previously observed only in individuals with prior affections of the skin (i.e. atopic dermatitis). Thus, individuals receiving dupilumab for CRSwNP may develop novel symptoms that require interdisciplinary management. Future studies on dupilumab in a real-world setting will be required to further explore its spectrum of side effects.