Injection site reactions after dupilumab or tralokinumab for atopic dermatitis.

Background: Injection site reaction (ISR) is a local phenomenon defined as a constellation of symptoms, including swelling, erythema, pruritus, and pain around the site of injection. Objective: ISR is reported as a frequent adverse event after subcutaneous injection (SCI) of several biologics. Methods: We performed an observational real-life study to compare dupilumab and tralokinumab as regards ISR, analysing frequency, duration and intensity of symptoms related to SCI. From January 2023 to June 2023, we enrolled adult patients affected by moderate to severe AD and being on dupilumab or tralokinumab treatment. A 12 items questionnaire was administered to all enrolled patients. Results and conclusions: Three hundred and ninety-two patients were included. ISR was a frequent occurrence in both the treatment groups, with tralokinumab causing ISR more frequently than dupilumab. However, the reactions were generally mild and no patient stopped therapy.