Real-World Effectiveness and Safety of Anti-CGRP Monoclonal Antibodies in the Prevention of High-Frequency Episodic and Chronic Migraine in Romania-A Multicenter Retrospective Observational Study.

Background: Real-world evidence regarding the effectiveness and safety of anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies in Eastern European populations remains limited. We aimed to evaluate treatment outcomes and safety in Romanian patients with high-frequency episodic migraine (HFEM) and chronic migraine (CM). Methods: We conducted a multicenter retrospective observational cohort study including 113 adults with HFEM (n = 38) or CM (n = 75) who initiated treatment with galcanezumab, erenumab, fremanezumab, or eptinezumab at specialized headache centers in Romania. Monthly migraine days (MMDs) in HFEM and monthly headache days (MHDs) in CM were assessed at the baseline and during follow-up. Treatment outcomes, discontinuation, persistence, and adverse events were evaluated during routine clinical follow-up. Results: At month 6, headache frequency was substantially reduced in both groups, with median MMDs decreasing from 10 to 2 in patients with HFEM and median MHDs decreasing from 25 to 6 in patients with CM. A ≥50% reduction in headache frequency was achieved by 78.9% of patients with HFEM and 64.0% of those with CM. Among the patients with CM, 70.7% met the predefined criterion for conversion to episodic migraine at month 6. During follow-up, 22 patients discontinued treatment. Adverse events were reported in 28 patients (24.8%), were predominantly non-serious, and resulted in treatment discontinuation in 3 patients (2.7%). No serious adverse events were documented. Treatment persistence at 12 months was 82.3%. Conclusions: In this Romanian real-world cohort, anti-CGRP monoclonal antibody treatment was associated with substantial reductions in migraine/headache frequency in patients with HFEM and CM. The treatment was generally well-tolerated, with predominantly non-serious adverse events and a low rate of discontinuation due to adverse events. These findings provide real-world evidence from Romania and support further prospective evaluation of the long-term effectiveness and safety of anti-CGRP monoclonal antibodies.