Alopecia as an emerging adverse event to CGRP monoclonal antibodies: Cases Series, evaluation of FAERS, and literature review

BackgroundAlopecia is associated with erenumab post-marketing, but no cases have been described. MethodsWe describe two patients that reported temporary hair loss and review the FDA Adverse Event Reporting System (FAERS). ResultsThe first patient experienced alopecia within three months of starting erenumab, which did not improve with ongoing use or transition to fremanezumab. The second patient reported alopecia within two weeks of starting erenumab, which continued after transition to galcanezumab; months later, there was also recurrent hair loss within one month of starting fremanzeumab. According to FAERS (last accessed 18 August 2022), alopecia was reported most with erenumab (1158), followed by galcanezumab (554), fremanezumab (175), eptinezumab (23), rimegepant (26), ubrogepant (4), and atogepant (3). ConclusionMost events were reported in women and non-serious. The potential mechanism of alopecia with drugs targeting calcitonin gene-related peptide or its receptor possibly includes disruptions in the microvascular circulation and other homeostatic mechanisms.

Automated summary

This study describes two cases of temporary hair loss associated with erenumab and reviews the FDA Adverse Event Reporting System. The study found that there were the most reports of hair loss with erenumab, followed by galcanezumab and fremanezumab. Most of the events occurred in women and were non-serious. The potential mechanism of drug-induced hair loss targeting calcitonin gene-related peptide or its receptor may involve disruptions in microvascular circulation and other homeostatic mechanisms.