Anti-CGRP Monoclonal Antibodies in Chronic Migraine: A Position Statement of the Brazilian Academy of Headache and Orofacial Pain

Abstract

Background Chronic migraine (CM) is a disabling neurological condition with high burden, common comorbidities, and a frequent profile of treatment resistance. Although there is progress in mechanism-based therapeutic approaches, such as anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs), real-world data on their clinical use and positioning in Latin America remain limited. Methods A cross-sectional, expert-opinion survey of 21 Brazilian headache specialists was carried out to inform a position statement of the Brazilian Academy of Headache and Orofacial Pain. The electronic survey consisted of 49 structured questions that addressed clinical experience with CM, the prevalence of comorbid medication-overuse headache (MOH), the use of anti-CGRP mAbs fremanezumab and galcanezumab as treatment options, comparative assessment, therapeutic positioning, and consensus statements. Descriptive statistics were employed, and consensus was considered as 80% agreement. Results Twenty-one specialists participated; 14 (66.7%) had >20 years’ experience. Misdiagnosis was common (16 (81.0%)), and 12 (57.1%) had a diagnostic delay of one year or more. The rate of treatment resistance was high (13 (61.9%) reported that over half of patients were non-responders to two or more prior preventives), and the prevalence of MOH was also high (17 (81.0%) estimated 80% coexistence or higher). The anti-CGRP mAbs were the most used therapies (fremanezumab 17 (81.0%), galcanezumab 18 (85.7%)) and were perceived by respondents as effective in reducing migraine days and improving quality of life. Safety and tolerability ratings reported by clinicians were favorable, with the most common reactions being injection-site reactions. Most clinicians did not indicate notable differences among agents, although no statistical comparison was performed. Early use was prescribed in CM with MOH sufferers (17 (85.0%)). The primary barrier was cost (19 (90.5%)), followed by a strong agreement with earlier use and region-specific guidance. Conclusions Diagnostic delays, high treatment resistance, and significant comorbidity burden characterize CM management in Brazil. In the opinion of the surveyed specialists, anti-CGRP mAbs are perceived as effective and well tolerated, particularly in patients with MOH, and most respondents favored their earlier positioning in the treatment algorithm.