A Phase 2 Study of ONO-2808 in Patients With Multiple System Atrophy

Inclusion Criteria:

1. Female or male patients with a diagnosis of clinically-established orclinically-probable MSA according to the novel Movement Disorder Society (MDS)criteria for MSA diagnosis (2022), including patients with MSA of either subtype (MSA-P or MSA-C).

2. Patients at the early stages of the disease, defined as a maximum of 5 years sincethe onset of one of the following symptoms associated with MSA:

• Parkinsonism

• Ataxia

• Orthostatic hypotension and/or urinary dysfunction

3. Patients with an anticipated survival of at least 3 years in the opinion of theInvestigator.

4. Patients who are able to ambulate without the assistance of another person, definedas the ability to take at least 10 steps and then to turn around and walk at leastanother 10 steps. Use of assistive devices (e.g., walker or cane) is allowed.

5. Ability to swallow oral medication and be willing to adhere to the studyintervention regimen.

Exclusion Criteria:

1. Pregnant or lactating females.

2. Patients with a clinically-significant or unstable medical or surgical conditionother than MSA that, in the opinion of the Investigator, might preclude safecompletion of the study or might affect the results of the study (e.g., pulmonary,cardiovascular [including bradyarrhythmia], macular edema, and significant renal orhepatic dysfunction).

3. Neurological diseases/disorders other than MSA, such as Parkinson's disease,dementia with Lewy bodies, essential tremor, progressive supranuclear palsy,spinocerebellar ataxia, spastic paraparesis, corticobasal degeneration, or vascular,normal pressure hydrocephalus, pharmacological, or post-encephalitic parkinsonism.

4. Patients with documented liver diseases or cirrhosis.

5. Positive results at Screening for active viral infections that include positivehuman immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg) andhepatitis B core antibody, and hepatitis C virus (HCV).

6. Patients with suicide ideation according to the Investigator's clinical judgment perthe Columbia Suicide Severity Rating Scale (C-SSRS) at Screening or who have made asuicide attempt in the 6 months before Screening.