The PROMISE-2 trial (NCT02974153), which evaluated the efficacy of eptinezumab in patients with chronic migraine, assessed patient-identified most bothersome symptom (PI-MBS) as a unique patient-centered secondary endpoint. Roger Cady, MD, Lundbeck Pharmaceutical, discusses the utility of PI-MBS as a novel endpoint. Patients were asked to describe their MBS at screening and rated the overall change in its severity at subsequent follow-ups. PI-MBS was highly variable, with 23 different symptoms reported. PI-MBS improvement was strongly correlated with Patient Global Impression of Change (PGIC), suggesting resolution of PI-MBS has a substantial impact on how a patient feels overall. These findings suggest that PI-MBS may be a useful measure in preventive trials that assess the burden of symptoms that matter most to an individual. This interview took place during the European Academy of Neurology 2021 congress.