Real-world Efficacy of Erenumab on Migraine-associated Symptoms and Patient-reported Satisfaction Levels: A Retrospective Study in Japan.

Objective In randomized clinical trials and real-world studies, calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs), including erenumab, have demonstrated efficacy for migraine prevention. However, there have been no real-world studies focusing on erenumab in East Asia that investigated its efficacy on migraine-associated symptoms and patient-reported satisfaction levels. Methods This single-center, observational, retrospective, real-world study examined patients who received at least three doses of erenumab at Keio University Hospital, Tokyo, Japan, between December 2021 and March 2023 as their first CGRP mAb treatment in a real-world setting. The patients were administered 70 mg of erenumab monthly. We assessed changes in monthly migraine days (MMDs), responder rates, migraine-associated symptoms including photophobia, phonophobia, nausea/vomiting, and patient-reported satisfaction levels. In addition, injection site reactions and other adverse events were recorded to investigate safety. Results Nineteen patients were considered eligible for the analysis. At 3 months, erenumab decreased MMDs by 6.6 (95% confidence interval, 2.3-10.8; p<0.01). The 50% responder rate was 42%. A total of 83% (n=15), 56% (n=10), and 71% (n=10) of patients reported either improvement in or disappearance of photophobia, phonophobia, and nausea/vomiting, respectively, and 44% (n=8) and 28% (n=5) answered "very satisfied" and "somewhat satisfied", respectively, with erenumab treatment, leaving only 28% (n=5) as "unsatisfied". Injection site reactions (n=6, 32%) and constipation (n=4, 21%) were frequent adverse events. Conclusion In a real-world setting in Japan, erenumab proved to be effective in not only reducing migraine and headache frequency but also improving migraine-associated symptoms and satisfying the majority of patients.