Eptinezumab in Participants With Episodic Cluster Headache

Inclusion Criteria: * The participant has episodic cluster headache, as defined by International Headache Society (IHS) International Classification of Headache Disorders 3rd Edition (ICHD-3) classification, with an adequately documented record or reliable history of eCH of at least 12 months prior to Screening Visit 1. * The participant has a prior history of cluster period(s) lasting 6 weeks or longer, when untreated. * The participant is able to distinguish cluster headache attacks from other headaches (that is; tension-type headaches, migraine). * The participant is, at Screening Visit 2, in cluster headache bout, characterized by the presence of at least one typical cluster headache attack, that started not later than 1 week prior to Screening Visit 2. * The participant has a medical history of first symptoms of cluster headache from ≤60 years of age. Exclusion Criteria * The participant has experienced failure on a previous treatment targeting the calcitonin gene-related peptide (CGRP) pathway (anti-CGRP monoclonal antibodies \[mAbs\] and gepants). * The participant has confounding and clinically significant pain syndromes (for example, fibromyalgia, complex regional pain syndrome). * The participant has a history or diagnosis of hypnic headache, hemicrania continua, new daily persistent headache, chronic migraine or unusual migraine subtypes such as hemiplegic migraine (sporadic and familial), recurrent painful ophthalmoplegic neuropathy, migraine with brainstem aur…