Interim analysis of the real-world utilization and safety of onabotulinumtoxinA for the prophylactic treatment of chronic migraine in an observational study in the European Union

Abstract

Background:
OnabotulinumtoxinA is approved for chronic migraine (CM) headache prophylaxis with safety/ efficacy established in several controlled trials. However, it is important to evaluate utilization and safety in a real-world setting.

Aim:
Describe the safety and utilization of onabotulinumtoxinA for CM in routine practice.

Methods:
This is a prospective, observational, multinational, European post-authorization study (NCT01432379). Data are collected at the first study injection and approximately every 3 months for 52 weeks (utilization) or 64 weeks (safety). Data as of March 10, 2014 are summarized using descriptive statistics.

Results:
Physicians at 58 sites across UK, Germany, Spain, and Sweden collected data from 1160 patients. Average patient age was 47 years (SD ¼ 12); 84% female. To date, 162 patients (14%) completed the study and 2940 onabotulinumtoxinA treatments were administered across up to 6 treatment sessions per patient. In treatment session 1 (n ¼ 1160), the number of injections (mean ¼ 31) and specific muscle areas injected were similar between countries; majority of patients (78%) received 150–200 total dose units. 227 patients (20%) reported 1 treatment-related AE (TRAE) resulting in 33 (3%) discontinuations; 1 TRAE was serious (worsening migraine). Most commonly reported TRAEs: neck pain (3%) and eyelid ptosis (3%). Three patients (0.3%) reported treatment related dysphagia.

Conclusions:
Safety/tolerability data are consistent with previously published findings, which is in line with the known safety profile of onabotulinumtoxinA for CM. No unexpected TRAEs were reported. OnabotulinumtoxinA utilization during treatment session 1 appears to be consistent with aspects of the published PREEMPT injection paradigm