1. Patients with episode cluster headaches randomized to receive galcanezumab experienced a greater decline in frequency of headaches 1 to 3 weeks after treatment compared to placebo treated patients.
2. Injection-site pain occurred in patients receiving galcanezumab, though no notable differences in overall adverse events was seen between treatment and placebo groups.
Evidence Rating Level: 1 (Excellent)
Study Rundown: Episodic cluster headaches are a disabling condition that occurs in bouts separated by headache free periods. Reduced quality of life is associated with the headaches, affecting patient’s daily functioning, work, and mental health. Present treatment is aimed at reducing frequency of the attacks, though no medication is specifically approved for prevention the condition. The antibody galcanezumab, which binds and inhibits the calcitonin gene-related peptide (CGRP), has been effective for migraine treatment and its use for cluster headaches is of interest. The primary outcome of the study, reduction in headache frequency from weeks 1 to 3 of the study, showed a significantly higher reduction in galcanezumab treated patients compared to those treated with placebo. While those in the treatment group experienced a higher rate of injection site pain, no notable difference in adverse events was observed between the treatment groups.
This study provides supporting evidence for a first-in-class treatment for episodic cluster headaches by showing notable declines in headache frequency in treated patients, though the size of the trial and length of follow-up are both weaknesses that may limit the study’s impact.