P2B001 is an investigational drug that comprised of low doses of two drugs, pramipexole and rasagiline, which are both approved drugs and routinely used in standard therapy for Parkinson's disease. The two drugs work in two different mechanisms that help each other, so there is a reason to believe that their combined activity will be better than each individual drug, and that lower doses can be used without losing the therapeutic effect. Thus, the development of P2B001 is intended to provide a combination of low doses of these two drugs, in an improved formulation, that is hoped to be more effective in controlling Parkinson's disease symptoms and with less side effects than each of the drugs taken alone or the current available commercial drugs taken together. In a previously completed clinical trial a significant improvement in Parkinson's disease symptoms was seen in patients treated with P2B001 compared to patients that were treated with placebo.

In this phase 3 study , the safety and efficacy of P2B001 will be assessed by comparing P2B001 to its individual components pramipexole and rasagiline. This will be done by monitoring the motor and non-motor symptoms, evaluating responses participants provide on questionnaires relating to Parkinson's disease and quality of life that will be completed on every visit. In addition, this study will also compare P2B001 to a marketed drug of pramipexole ER. Approximately 525 patients will participate in this research study and the participation in this study will last between 14 to 18 weeks.

A total of 525 eligible subjects with early untreated Parkinson's disease (PD), will be randomized to 4 treatment groups. Each subject will participate in the study for approximately 18 weeks including a 30 day screening period, 12 week treatment period, and 2 weeks follow-up period. Subjects will be requested to take one capsule and 1-3 tablets of study drug by mouth with a glass of water every day for 13 weeks. The study requires seven visits to the clinic one every 2-4 weeks.

Inclusion Criteria:

1. Subject has Parkinson's disease consistent with the UK Brain Bank Criteria and must have bradykinesia with sequence effect. If rest tremor does not exist must have prominent asymmetry of motor function.
2. Subject with disease duration less than 3 years since diagnosis.
3. Subject has a H&Y stage score of < 3.
4. Subject has a MMSE score ≥ 26.

Exclusion Criteria:

1. Subject has an atypical parkinsonian syndrome or secondary parkinsonism
2. Subject has previous exposure to levodopa or a dopamine agonist for longer than 4 weeks; if previous exposure was less than 4 weeks then it must not be within 2 months prior to the baseline visit.
3. Subject has previous exposure to a MAO-B inhibitor for longer than 4 weeks; if previous exposure was less than 4 weeks then it must not be within 3 months prior to the baseline visit.
4. Subject who has taken anticholinergic drugs for PD or amantadine for longer than 4 weeks; if previous exposure was less than 4 weeks then it must not be within 1 month prior to the baseline visit.
5. Subject has moderate (Child-Pugh categorization B, score 7-9) or severe (Child-Pugh categorization C, score 10-15) hepatic impairment.

double blind study