(A-033) Utilization of erenumab and other prophylactic migraine treatments: a regulator-mandated population-based cohort study in four Nordic countries (EUPAS36014)

Background: Erenumab is a monoclonal antibody authorized in Europe for prophylaxis of migraine in adults who have at least 4 migraine days per month. This drug utilization study is a post-approval commitment to the European Medicines Agency.

Objectives: Primary objective: to describe utilization of erenumab among patients with migraine. Secondary objective: to identify suitable comparators for a potential safety study with comparative analysis. Exploratory objective: to estimate rates of pre-specified cardiovascular (CV) endpoints among patients with migraine initiating erenumab or other prophylactic migraine medications.

Methods: This cohort study was based on routinely collected secondary data from population-based registries in Denmark, Finland, Norway and Sweden, all with universal health care. The study population included adult patients with migraine classified into the following cohorts, according to the treatment initiated between 08-Aug-2018 and 30-Sep-2022: Erenumab (ERE), other calcitonin gene-related peptide inhibitors (OCG), botulinum toxin (BOT), or other prophylactic migraine medications (OPM). For erenumab, utilization measures examined were prescriber specialty and sector, persistence, discontinuation, and switching. All treatment cohorts were characterized in terms of demographic and clinical characteristics. Rates of CV endpoints, per 1000 person-years, were computed in each treatment cohort, with follow-up through Dec 2022. All analyses were descriptive.

Results: There were 20,218 initiators of erenumab: 1835 in Denmark, 4949 in Finland, 8276 in Norway, and 5158 in Sweden. Erenumab was primarily prescribed in specialist care. Overall, 17,129 (84.7%) of the erenumab initiators were women, and median age at erenumab initiation was 43.7 years. There were 16,515 patients in the OCG cohort, 16,648 in the BOT cohort, and 227,389 in the OPM cohort. Hypertension (based on diagnosis or treatment proxy) was the most common comorbidity, with rates of hypertension per 1000 person-years, 130 ERE, 161 OCG, 259 BOT, and 454 in OPM. Rates of other CV outcomes were low, with most treatment cohorts having no events.

Conclusions: Uptake and utilization of erenumab varied by country. ERE, OCG, and BOT cohorts had similar patient characteristics, and all were different from the OPM cohort. For a potential comparative analysis, use of more than one active comparator, from different drug classes, is optimal, provided the indicated population is reliably identified. Overall rates of CV events were low.