Background: In DELIVER, eptinezumab reduced migraine frequency and was well tolerated in patients with migraine and prior preventive treatment failures. This analysis evaluated changes in patient-reported outcomes (PROs). Methods: DELIVER (NCT04418765; phase 3b double-blind study) randomized adults with migraine and 2-4 prior preventive treatment failures to eptinezumab or placebo every 12 weeks. The assessed PROs included EuroQol 5-Dimensions 5-Levels visual analogue scale (EQ-5D-5L VAS); 6-item Headache Impact Test (HIT-6), Patient Global Impression of Change (PGIC), most bothersome symptom (MBS), and Migraine-Specific Quality of Life Questionnaire (MSQ, v2.1). Results: Patients received eptinezumab 100mg (n=299), 300mg (n=294), or placebo (n=298). Mean changes from baseline to Wk12 in EQ-5D-5L VAS scores were 2.0 (100mg, P=0.0007) and 4.4 (300mg, P<0.0001) versus -3.1 (placebo), and were maintained or further improved to Wk24 (2.0, 5.2, -2.8, respectively). Mean baseline HIT-6 total scores were ~66.4, with mean changes of -6.9 (100mg, P<0.0001) and -8.5 (300mg, P<0.0001) versus -3.1 (placebo) at Wk12 that were further improved through Wk24 (-8.9 and -9.9 vs -3.9). PGIC, MBS, and MSQ domain scores showed greater improvement for eptinezumab than placebo. Conclusions: In adults with migraine and prior preventive treatment failures, eptinezumab robustly improved health-related quality of life and migraine-related burden over 24 weeks versus placebo.