PO-51 | Rimegepant combined with valproic acid and botulinum toxin in refractory hemiplegic migraine: a case report

Gianni Difonzo, Cinzia Tamborino, Adriana Fallacara, Damiano Paolicelli, Maria Pia Prudenzano | Headache Center, “L. Amaducci” Neurological Clinic, Policlinico General Hospital, Bari, Italy

Background: Hemiplegic migraine (HM) is a rare subtype of migraine with aura, characterized by transient motor weakness, often accompanied by visual, sensory and language disturbances. Preventive treatment is challenging due to rarity of the condition and limited evidence. Calcitonin gene-related peptide (CGRP) pathway antagonists, like rimegepant, have shown promise in chronic migraine treatment. Although theoretical concerns regarding potential effects on aura or cerebrovascular mechanisms exist a growing body of evidence indicates that these agents may be both effective and well tolerated in carefully selected patients. This case report explores the potential of combining rimegepant with other preventive treatments in managing a complex case of HM resistant to multiple therapies.

Methods: A 27-year-old male with a long-standing history of both chronic migraine without aura and sporadic HM presented with frequent, disabling attacks that were unresponsive to multiple preventive therapies. These included amitriptyline, topiramate, beta-blockers, flunarizine, dihydroergotamine, acetazolamide, pizotifen, verapamil, lamotrigine, fremanezumab, and the ketogenic diet. Additionally, two occipital nerve blocks and one sphenopalatine ganglion block failed. The patient showed a partial response to valproic acid and botulinum toxin, with a reduction in attack intensity: both treatments were therefore continued. In February 2024, rimegepant 75 mg every other day was added to his treatment regimen. Clinical monitoring was conducted using structured headache diaries and regular neurological follow-up.

Results: Before starting rimegepant, the patient experienced near- daily migraine without aura (28/month) and 14 episodes of HM in 2023. During rimegepant therapy, the frequency of migraine without aura decreased to approximately 10 moderate-intensity migraine days per month. Notably, HM episodes were also reduced in both frequency (5 in 2024) and severity, with shorter duration. No serious adverse effects or aura worsening were reported and the treatment was well tolerated.

Conclusion: This case highlights the potential role of combination therapy, including rimegepant, valproic acid, and botulinum toxin, in managing resistant hemiplegic migraine. Although theoretical concerns about CGRP antagonists remain, this case supports emerging evidence that CGRP antagonists can be safe and effective in selected HM patients. Further studies are needed to better understand the safety and efficacy of CGRP-targeting therapies in this unique population.