Efficacy and safety of galcanezumab for cluster headache preventive treatment: a systematic review and meta-analysis.

Background: Galcanezumab is a monoclonal antibody targeting the CGRP pathway and represents the latest disease-specific and mechanism-based therapeutic option for cluster headache (CH).

Objective: We performed a systematic review and meta-analysis to evaluate the efficacy and safety of galcanezumab for CH.

Methods: We searched PubMed, Embase, and Cochrane Library for studies implementing galcanezumab for episodic and chronic CH. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Reporting Guidelines for Meta-analyses of Observational Studies (MOOSE) guidelines. The primary outcome was efficacy, defined by a reduction from the baseline of at least 50% in the weekly frequency of CH attacks and the Patient Global Impression of Improvement scale (PGI-I). Secondary outcomes included treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs).

Results: A total of 504 patients were included from 6 studies, of which 2 were RCTs. The follow-up period ranged from 3 weeks to 15 months. The mean age was 44.4 ± 10.2 years, with 24.4% female patients. Overall efficacy was 76.0% (95% CI 0.67-0.85), TEAEs were observed in 48.0% of patients (95% CI 0.25-0.72), and the most common were nasopharyngitis, local injection pain, and local injection swelling. TEAEs were, however, considerably higher within the 300 mg dose group compared with the 240 mg dose group, 80.0% (95% CI 0.65-0.87) versus 28.0% (95% CI 0.12-0.47), respectively.

Conclusion: This meta-analysis suggests that galcanezumab is effective in reducing the number of CH attacks and can be considered a safe medication.