Real world effectiveness of anti-CGRP monoclonal antibodies over three consecutive one-year treatment cycles: An intention-to-treat analysis

BackgroundThe present prospective, real-world study aims to assess anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) effectiveness across three consecutive one-year treatment cycles by means of a conservative intention-to-treat (ITT) analysis.MethodsWe enrolled 179 subjects (75.4% females, 51.3 years 95% confidence interval [49.2-53.4] years), 87.2% with chronic migraine and medication overuse) who started mAbs between 2018 and 2020. We recorded clinical data supported by a prospectively filled headache diary up to three one-year treatment cycles. The ITT analysis was performed with a multivariate linear mixed model considering the entire population.ResultsWe observed a marked and consistent reduction in monthly migraine days (MMDs) across the three one-year cycles of treatment: -12.7 )[-11.4 - -14.1] at end of the first year of treatment (C1), -12.4 [-11.0 - -13.8] at the end of the second year (C2) and -12.9 [-11.4 - -14.3] at the end of the third year (C3). Baseline and residual MMDs progressively decreased across the three cycles (<i>p</i> <i>=</i> 0.008): from 21.1 [19.8-22.4] to 9.6 [8.3-11.0] in C1, from 19.0 [17.4-20.5] to 9.6 [8.1-11.1] in C2, and from 15.9 [14.3-17.5] to 8.5 [6.9-10.1] in C3. At the end of C3, the 50% response rate was 38.5% (69/179)<i>.</i>ConclusionsIn our cohort, mAbs induced a meaningful and sustained reduction in MMDs across three consecutive one-year cycles of treatment. The ITT analysis revealed a remaining high burden of disease. While confirming mAbs effectiveness in migraine prevention, these findings underscore the need for more treatment approaches and for exploring other non-CGRP dependent pathways.