A Study to Evaluate Safinamide's Effect on Dopamine and Serotonin's Availability by Using Brain Imaging

This is a study of safinamide, an investigational drug for Parkinson disease (PD). Safinamide is being developed as add-on therapy for the treatment of Parkinson disease. It is theorized that safinamide acts by increasing the available dopamine in those areas of the brain where dopamine is decreased as a result of Parkinson;s Disease. . Dopamine in the brain is involved in controlling body movements. Safinamide has been extensively studied in animals, and has been shown to increase the level of dopamine in these animals. Safinamide has also been tested in patients with Parkinson disease. The goal of this research trial is to see if safinamide is safe and well tolerated and to better understand how it affects the dopamine system in the brain in individuals with Parkinson disease. Data from this trial may provide essential information about the effectiveness and safety of these doses of safinamide in patients with early Parkinson disease, who are already receiving a stable dose of their normal Parkinson disease treatment.


Eligibility Criteria:
Inclusion Criteria:

1. Male or female, between 40-80 years of age.
2. Subject must have a diagnosis of idiopathic Parkinson's disease, and a Hoehn and Yahr stage of I-III.
3. Subjects must be concomitantly treated with a stable dose of a single dopamine agonist prior to the screening visit.
4. Subjects must be able to understand and willing to sign an approved Informed Consent form.
5. Female subjects must be neither pregnant or breast-feeding.

Exclusion Criteria:

1. Subjects with any form of Parkinsonism other than idiopathic Parkinson's disease.
2. Subjects currently experiencing motor fluctuations (end of dose wearing off), dyskinesias, or significant postural hypotension.
3. Subjects treated with l-dopa, anticholinergics, amantadine, MAO inhibitors, COMT inhibitors, tricyclic antidepressants, and / or SSRI and SNRI antidepressants.
4. Subjects with a history of psychosis, either previously or currently, or a score ≥ 3 on item 2 or 3 of the UPDRS Part I.
5. Subjects with evidence of dementia or cognitive dysfunction.
6. Subjects with current diagnosis of substance abuse or history of alcohol or drug abuse in the past three months.
7. Subjects with current clinically significant gastrointestinal, renal, hepatic, endocrine, pulmonary or cardiovascular disease, including hypertension that is not well controlled, asthma, chronic obstructive pulmonary disease, and Type I diabetes.
8. Subjects with a concomitant disease likely to alter absorption, metabolism or elimination of the study drug.
9. Female subjects must be neither pregnant nor lactating.
10. Subjects with hypersensitivity or contraindications to MAO-B inhibitors.
11. Subjects with a neoplastic disorder, which is either currently active or has been in remission for less than one year.
12. Subjects with second- or third-degree atrio-ventricular block or sick sinus syndrome, uncontrolled atrial fibrillation, severe or unstable angina, congestive heart failure, myocardial infarction within three months of the screening visit, or significant ECG abnormality, including QTc ≥ 450 msec (males) or ≥ 470 msec (females), where QTc is based on Bazett's correction method.
13. Subjects with a history or a current diagnosis of human immunodeficiency virus infection, or tests positive for Hepatitis B surface antigen, tests positive for Hepatitis B core antibody, but negative for Hepatitis B surface antibody, or tests positive for Hepatitis C antibodies.
14. Subjects who have participated in a previous clinical trial with safinamide, have participated in a previous clinical trial within 30 days of entry into the study, or have received treatment with any investigational compound within thirty days or five half-lives, whichever is longer, prior to screening.
15. Subjects with any abnormality that the investigator deems to be clinically relevant.
16. Legal incapacity or limited legal capacity
17. Other significant disease that in the Investigator's opinion would exclude the subject from the trial.
18. Treatment with a drug that has hepatotoxic potential within 4 weeks, or received radiation therapy or a drug with cytotoxic potential within one year prior to the screening visit.
19. Ophthalmologic history including any of the following conditions: albino subjects, family history of hereditary retinal disease, progressive and/or severe diminution of visual acuity, retinitis pigmentosa, retinal pigmentation due to any cause, any active retinopathy or ocular inflammation, or diabetic retinopathy.