(B-106) Adherence to risk minimization measures for alemtuzumab use in Multiple Sclerosis: a drug utilisation study in four European countries

Background: Additional risk minimisation measures were added to the EU SmPC for alemtuzumab in January 2020. These included: restricted indication; new contraindications; and newly required monitoring before, during, and after infusion.

Objectives: Primary objectives were to measure: 1a) proportion of newly treated patients with the revised indication; and 1b) proportion of courses without contraindications, per revised SmPC.
Secondary objectives were to measure: 2a) proportion of courses with cardiac monitoring, full blood count (FBC)/transaminases/creatinine, urinalysis and thyroid function testing 30 days prior to infusion; cardiac and platelet testing during infusion; and 2b) percentage adherence, at patient level, to long-term monitoring of FBC/transaminases/creatinine and urinalysis (monthly) and thyroid function (trimonthly), per revised SmPC.

Methods: This was a descriptive cohort study. Patients with multiple sclerosis (MS) and treated with alemtuzumab were included. Data sources included; administrative data from AIM-IMA (Belgian Social Security database), ReMuS (Czech MS registry), chart review data from three UK centres (Cardiff, Cambridge, Plymouth), and an ongoing cohort study in Germany (TREAT-MS). Study period was January 2020 to the data cut-off for each source (March 2022 - January 2024). Descriptive proportions were calculated to address each objective, at either patient or course level.

Results: Objective 1a (indication): Using a 12-month assessment period, the revised indication was met in 100% (AIM-IMA), 66.7% (UK centres, 79.5% with 24-month assessment), 66.7% (ReMuS, increasing to 75.3% after manual checking), and 87.5% (TREAT-MS) of patients.
Objective 1b (contraindication): The majority of courses had no contraindication; 77.5% (AIM-IMA) - 97.8% (TREAT-MS).
Objective 2a (monitoring prior / during infusion): Approximately >70% of courses had prior heart rate [HR], blood pressure [BP] and FBC tests. Urinalysis and thyroid function testing were an exception in UK. During the infusion, ≥80% of courses had HR and BP monitoring. Platelet testing on Day 3 or 5 of infusion was observed in 29%-51% courses.
Objective 2b (long-term monitoring): Adherence was approximately >50% for all tests, even in years 3-4 post-infusion, except for urinalysis and thyroid function testing in the UK.

Conclusions: There is concordance with the revised SmPC. Overall adherence to long-term monitoring was satisfactory, even considering the impact of COVID-19 on healthcare access. Low adherence, e.g. urinalysis in the UK, was qualitatively explained.