Treatment of hemiplegic migraine with anti-calcitonin gene-related peptide monoclonal antibodies: A case series in a tertiary-care headache center

Hemiplegic migraine (HM) is a subtype of migraine with aura that includes motor weakness; such headaches can be excruciating. The presence of not only headache but also aura symptoms of HM increase the burden on patients, and the treatment of HM is sometimes challenging. Monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway are novel migraine preventive treatments that have shown promising efficacy in patients with migraine; however, there have been no reports regarding their efficacy in HM to date. Six patients with HM were treated with galcanezumab in a tertiary-care headache center. After 3 months of treatment, the number of monthly days with headache of at least moderate severity was reduced in three patients. The number of days each month with weakness was also reduced in four patients. Furthermore, the Patient's Global Impression of Change and change in Migraine Disability Assessment total score, were improved in five of the six patients after the treatment; however, the change from baseline in days with bothersome symptoms did not show any specific trends in our patients. Notably, no adverse events were reported during the treatments. The mechanism underlying the improvement in aura symptoms in our patients is not clear; however, we speculate that a small amount of CGRP mAbs have a direct mode of action in the central nervous system; alternatively, blocking the CGRP pathway in the periphery may secondarily inhibit cortical spreading depression. While prudence must be practiced, galcanezumab was still generally effective in HM and well tolerated. Further prospective clinical studies will more clearly elucidate the effects of CGRP mAbs in patients with HM.