Galcanezumab’s consistency of effect for episodic cluster headache (ECH) across multiple cluster periods was assessed, based on individual patient responses on Patient Global Impression of Improvement(PGI-I).

CGAL was Phase3 randomized, double-blind, placebo-controlled study of galcanezumab in ECH.

Patients (1:1 randomization) received placebo/galcanezumab 300mg subcutaneously once monthly for 2 months. Patients completing double-blind treatment+4-month post-treatment follow-up CGAL phases enrolled in Phase3b single-arm, open-label safety CGAR study. In both studies, PGI-I responses(1=very much better/2=much better/3=a little better/4=no change/5=a little worse/6=much worse/7=very much worse) were collected at 1-month following galcanezumab’s first administration. Individual PGI-I responses were evaluated for agreement using kappa coefficient by dichotomizing PGI-I scores into binary Yes/No scores for achieving following responses:PGI-I response=1/2/(Yes/No) and PGI-I response=1/2/3/(Yes/No).

39 patients from CGAL enrolled in CGAR and reported being in active cluster period at first dosing visit and had valid PGI-I data at month-1 in both studies (21 were treated with galcanezumab during treatment phase of CGAL and had distinct cluster periods during CGAL and CGAR). Among 21 CGAL patients receiving galcanezumab, 17 had PGI-I score=1/2, corresponding to feeling “very much better”/“much better”, at month-1(CGAL). Twelve(70.6%) of these 17 CGAL patients had same score at month-1(CGAR). Four CGAL patients who did not have PGI-I score=1/2 at month-1 did not achieve PGI-I score=1/2 at month-1 in CGAR. Kappa-coefficient=0.478 indicates agreement between PGI-I scores at month-1 in both studies. Among 18 galcanezumab-treated patients with PGI-I score=1/2/3 in month-1(CGAL), 15(83.3%) had the same score at month-1(CGAR). Of 3 patients who did not have score=1/2/3 in CGAL, 2(66.7%) had PGI-I score=1/2/3 in CGAR (kappa-coefficient=0.146).

There was good agreement on PGI-I between two CH periods, following galcanezumab’s first dose at month-1. Majority of patients reported improvement in PGI-I scores in two distinct CH bouts suggesting that galcanezumab demonstrates consistent effect in ECH patients.