Study Evaluating the Efficacy, Safety, and Tolerability of ASY202 (Dihydroergotamine Mesylate [DHE] Inhalation Powder Delivered Via a Multidose Dry Powder Inhaler) for the Acute Treatment of Migraine in Adult Patients

This study is testing an investigational inhaled migraine medication to see how well it works, how safe it is, and how well people tolerate it. Adults with migraine will receive both the study medication (ASY202) and a placebo (inactive treatment) at different times during the study. Neither participants nor study staff will know which treatment is given at the time. The medication is taken using a handheld dry powder inhaler to treat migraine attacks when they occur. Following screening, eligible participants will be enrolled and randomized to one of two treatments sequences i.e. one treatment sequence will receive ASY202 in treatment period 1 followed by placebo in treatment period 2 and other treatment sequence will receive placebo in treatment period 1 followed by ASY202 in treatment period 2. The study lasts about 16 weeks and includes a screening period, two treatment periods (with a minimum of 7 days washout period between the treatment periods), and a safety follow-up visit.

Inclusion Criteria: * Able to understand study procedures and provide written informed consent * Male or female, 18-65 years of age at Screening * BMI between 18.5-35 kg/m² at Screening * Documented history of migraine (with or without aura) for ≥1 year, consistent with the International Classification of Headache Disorders, 3rd Edition (ICHD-3) * Female participants must be either: * of non-childbearing potential, or * of childbearing potential using protocol required contraception Exclusion Criteria: * Diagnosis of headache conditions other than migraine * History or current diagnosis of coronary artery disease (CAD) * History or current diagnosis of coronary artery vasospasm (including Printz-metal's angina), clinically significant arrhythmia (e.g., ventricular tachycardia, ventricular fibrillation) or peripheral vascular disease, ischemic disease (e.g., Raynaud's syndrome, ischemic bowel syndrome, angina pectoris, myocardial infarction, or documented silent ischemia) * History of percutaneous coronary intervention, cardiac surgery, sepsis or vascular surgery * History or current diagnosis of cerebrovascular disease, including but not limited to stroke, transient ischemic attack, cerebral hemorrhage, or subarachnoid hemorrhage * Known history or current diagnosis of psychological and/or psychiatric condition that, in the opinion of the Investigator, might interfere with study participation and assessments or participant safety. These conditions may include depression, psychosis, schizophrenia, bipolar disorder, dementia, alcoholism, drug abuse, etc. * Known allergic reactions, hypersensitivity, or contraindications to DHE, other ergot-derived products, or any other excipient in the formulation * Use of strong or moderate CYP3A4 inhibitors within 14 days (or 5 half-lives) or CYP3A4 inducers within 28 days (or 5 half-lives) prior to Randomization * Any clinically significant symptoms or conditions at screening, other than migraine, including but not limited to central nervous system (e.g., seizures), cardiac, pulmonary, metabolic, renal, hepatic, or gastrointestinal conditions, or history of such conditions that in the opinion of the Investigator, might interfere with study assessments or participant safety