BACKGROUND: The European Union Summary of Product Characteristics (EU SmPC) for alemtuzumab in multiple sclerosis (MS) was revised in January 2020 under an Article 20 EU-pharmacovigilance procedure to include a revised indication, additional contraindications, and new monitoring requirements.

OBJECTIVES: To evaluate adherence to the revised SmPC for alemtuzumab across four European countries.

DESIGN: Descriptive cohort study using secondary healthcare data recorded between January 2020 (date of alemtuzumab EU SmPC revision) and the latest database update in each data source (ranging from March 2022 to January 2024).

METHODS: Data are used from: the Czech Republic MS registry (ReMuS), a cohort study of patients treated with alemtuzumab in Germany (long-Term study foR obsErvAtion of Treatment with alemtuzumab in active relapsing-remitting MS (TREAT-MS)), chart review data from three United Kingdom (UK) centers, and administrative healthcare data from the Belgian Social Security database (L'Agence InterMutualiste-Het InterMutualistisch Agentschap (AIM-IMA)). Adherence to revised indications, contraindications, and safety monitoring was summarized descriptively.

RESULTS: Data from 2046 people with MS treated with at least one course of alemtuzumab were assessed. Of 155 patients evaluable for adherence to the indication, 66.7% met the revised indication in ReMuS (n = 54/81; increasing to 75.3% after manual checks), 87.5% in TREAT-MS (n = 7/8), 66.7% in UK centers (n = 26/39; increasing to 79.5% in sensitivity analyses), and 100.0% in AIM-IMA (n = 22). Of 549 courses evaluated, 77.5%-97.8% were not contraindicated. While adherence to safety monitoring tests varied, heart rate and blood pressure were recorded for ⩾77.5% of courses before treatment and ⩾83.1% of courses during treatment. Platelet testing was conducted for 29.1%-51.4% of courses during treatment. Adherence to long-term (up to month 48) post-infusion monitoring was approximately 50%.

CONCLUSION: Alemtuzumab was prescribed in accordance with the indication in 67%-88% of patients included in this study. It was prescribed in accordance with the listed contraindications in 78%-98% of courses included in the study. Adherence to the monitoring schedule is adequate to maintain the benefit-risk profile of alemtuzumab.

TRIAL REGISTRATION: This study was registered in the Heads of Medicines Agency European Medicines Agency (EMA) catalog (EUPAS42540). Results are available on the EMA website: https://catalogues.ema.europa.eu/node/3602/resources.