Inclusion Criteria:  Participant has clinical features of parkinsonism. Participant has evidence of autonomic dysfunction. Participant has at least one supportive clinical feature of MSA. Participant is ambulatory.  Exclusion Criteria:  Participant has long duration of motor symptoms. Participant has advanced disease. Participant has structural brain abnormality on MRI. Participant has any significant neurological disorder other than MSA. Participant has an unstable medical or psychiatric illness.