Efficacy, tolerability, and safety of eptinezumab in patients with a dual diagnosis of chronic migraine and medication-overuse headache : Subgroup analysis of PROMISE-2

Objective: To evaluate the efficacy, tolerability, and safety of eptinezumab 100 and 300 mg compared with placebo in patients with the dual diagnosis of chronic migraine (CM) and medication-overuse headache (MOH). Background: Eptinezumab, a humanized monoclonal antibody targeting calcitonin gene-related peptide, may be effective for treating patients with a dual diagnosis of CM and MOH. Methods: PROMISE-2 (NCT02974153) was a double-blind, randomized, placebo-controlled, phase 3 study that comprised a screening visit, a 28-day pretreatment period, and a 32-week study duration. Patients in this exploratory analysis of a prespecified subgroup had confirmed diagnoses of both CM and MOH at screening. Patients were randomly assigned to receive intravenous eptinezumab 100, 300 mg, or placebo every 12 weeks. Efficacy outcomes included mean changes from baseline in monthly migraine days (MMDs) during weeks 1–12, migraine responder rates at week 12, and percentages of patients below International Classification of Headache Disorders thresholds for CM and MOH over weeks 1–24. Results: There were 431 patients who were diagnosed with CM and MOH as specified in the protocol and received eptinezumab 100 mg (n = 139), 300 mg (n = 147), or placebo (n = 145). During the baseline period, these patients experienced an average of 16.7 migraine days across treatment arms. Over weeks 1–12, eptinezumab-treated patients experienced greater reductions from baseline in MMDs than placebo patients (100 mg, change from baseline = −8.4, difference from placebo [95% confidence interval (CI)] = −3.0 [−4.56, −1.52], p