Discontinuing monoclonal antibodies targeting CGRP pathway after one-year treatment: an observational longitudinal cohort study

Abstract Background Monoclonal antibodies anti-calcitonin gene-related peptide (mAbs anti-CGRP) pathway are effective and safe on migraine prevention. However, some drug agencies limited these treatments to one year due to their high costs. This study aimed at evaluating the effect of discontinuing mAbs anti-CGRP on monthly migraine days (MMDs) and disability in high-frequency episodic (HFEM) and chronic migraine (CM) patients. Methods This observational longitudinal cohort study was conducted at 10 Italian headache centres. Consecutive adult patients were followed-up for three months (F-UP1–3) after discontinuation of a one-year erenumab/galcanezumab treatment. The primary endpoint was the change in F-UP MMDs. Secondary endpoints included variation in pain intensity (Numerical Rating Scale, NRS), monthly acute medication intake (MAMI), and HIT-6 scores. We also assessed from F-UP1 to 3 the ≥50% response rate, relapse rate to CM, and recurrence of Medication Overuse (MO). Results We enrolled 154 patients (72.1% female, 48.2 ± 11.1 years, 107 CM, 47 HFEM); 91 were treated with erenumab, 63 with galcanezumab. From F-UP1 to F-UP3, MMDs, MAMI, NRS, and HIT-6 progressively increased but were still lower at F-UP3 than baseline (Friedman’s analysis of rank, p