Abstract: Background: Nemolizumab is approved for the treatment of moderate-to-severe atopic dermatitis in patients aged ≥12 years, combined with topical corticosteroids and/or calcineurin inhibitors, when the disease is not adequately controlled by topical prescription therapies. Given the limited duration of follow-up in clinical trials and the current lack of postmarketing surveillance data, further investigations to evaluate the long-term safety profile of nemolizumab are urgently needed.
Methods: Adverse event (AE) signals were identified using disproportionality analysis with four algorithms: the reporting odds ratio (ROR), proportional reporting ratio, information component, and empirical Bayesian geometric mean. The data analyzed were from the FDA Adverse Event Reporting System, covering the period from the first quarter of 2024 to the second quarter of 2025.
Results: The three most frequently reported AEs were pruritus, rash, and headache. The top three AE signals with ROR values were eczema herpeticum, pemphigoid, and dermatitis exfoliative generalized. Specific AEs included injection site hemorrhage, injection site discoloration, eyelid edema, and urticaria. Notably, sleep disorder and eosinophil count emerged as new AEs.
Conclusion: These findings provide a comprehensive real-world safety overview of nemolizumab, highlighting both expected and emerging risks to inform clinical monitoring and risk management strategies during patient treatment.
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