Impact of COVID-19 on chronic migraine treated with erenumab: a case report.

BACKGROUND: Headache is a frequent symptom of the novel coronavirus 19 disease (COVID-19). To date, there are limited information on how COVID-19 affects migraine and its treatment. CASE DESCRIPTION: A 47-year-old patient, suffering from chronic migraine and medication-overuse headache, in September 2020 started erenumab at 70 mg once monthly. Two months later, monthly migraine days decreased from 20 to 5. On the third month, the patient developed mild COVID-19 symptoms, experiencing extreme fatigue, hyposmia, and attention deficit, resulting positive for SARS-Cov-2 RNA. A significant increase in migraine attacks frequency was reported. Brain MRI and EEG were normal. Erenumab was increased to 140 mg/month, and attacks decreased to 3 monthly migraine days and remained stable. All the headaches experienced by our patient during the infection fulfilled the criteria of the migraine attacks, without tensive-like features. CONCLUSION: We report the first case showing the effects of SARS-CoV-2 infection in a patient with chronic migraine and medication-overuse headache treated with erenumab. Our case description suggests that inflammatory processes induced by SARS-CoV-2 infection may increase the frequency of migraine attacks, probably through an activation of the trigeminovascular system. Whether treatment with CGRP receptor antagonist may influence COVID is still debated. Additional studies regarding anti-CGRP monoclonal antibodies in COVID-19 patients are warranted.