["parkinson's disease", 'healthy']
['biib054', 'placebo']

        Key Inclusion Criteria:

          1. All women of childbearing potential and all men must practice effective contraception
             during the study and for 6 months after their last dose of study treatment.

          2. Must have a body mass index from 19 to 32 kg/m2, inclusive.

          3. Must be in good health as determined by the Investigator, based on medical history,
             physical examination, and 12-lead ECG.

             For cohort 7 only:

          4. Diagnosis of idiopathic PD

        Key Exclusion Criteria:

          1. History of cardiovascular disease.

          2. Subject smokes more than 5 cigarettes or the equivalent in tobacco daily.

          3. Surgery within 3 months prior to Day -1 (other than minor cosmetic surgery and minor
             dental surgery, as determined by the Investigator).

          4. History or positive test result for hepatitis C, hepatitis B, or human
             immunodeficiency virus (HIV).

          5. Female subjects who are pregnant, currently breastfeeding, or attempting to conceive
             during the study.

        NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.
      