OBJECTIVES: Eptinezumab, a monoclonal antibody inhibiting CGRP, significantly reduced migraine frequency versus placebo in patients with chronic migraine (CM) in the randomized, double-blind PROMISE-2 study (NCT02974153). This analysis describes the effects of eptinezumab on the short-form Headache Impact Test (HIT-6) total and individual item scores in patients with CM.

METHODS: Patients received eptinezumab 100mg (n=356), 300mg (n=350), or placebo (n=366) for 2 intravenous doses administered at baseline and Week 12. Patients rated headache impact using the HIT-6 at baseline and Weeks 4, 12, 16, 24, and 32. HIT-6 item responses were scored from 1=never to 5=always, with higher scores indicating greater life impact. Post hoc two-piece, linear mixed-effects modeling examined longitudinal changes from baseline in HIT-6 scores. P-values are from post hoc analyses without multiplicity control.

RESULTS: Baseline headache impact was similar across treatment groups. Decreases in HIT-6 total scores from baseline to Week 4 were statistically significantly greater with eptinezumab versus placebo (p<0.0001); all groups demonstrated statistical significance versus baseline (p<0.0001). Over Weeks 4–32, all groups demonstrated stable HIT-6 total scores. At all post-baseline time points, mean HIT-6 total scores were lower in eptinezumab groups versus placebo (p<0.05). Scores for all individual items declined from baseline to Week 4 in all groups; reductions in eptinezumab groups were greater versus placebo (p<0.01). For all groups, HIT-6 item scores were generally stable over Weeks 4–32. Relative to placebo, impact levels were lower over Weeks 4–32 for all 6 items with eptinezumab 300mg (p<0.01). Scores for eptinezumab 100mg were lower than for placebo over Weeks 4–28 for 4 items and over Weeks 4–32 for 2 items (p<0.05).

CONCLUSIONS: Eptinezumab reduced headache-related life impact over the first month following intravenous administration relative to placebo; benefits were sustained through 32 weeks with just 2 administrations of eptinezumab.