The Unified Parkinson's Disease Rating Scale (UPDRS) consisted of 4 subsections used to assess symptoms and signs of Parkinson's disease, with an overall scale range of 0-147. Individual subsections included: I. Mentation, behavior, and mood (0-16); II. Activities of daily living assessed in both the "on" and "off" state (0-52); III. Motor examination (0-56); and IV. Complications of therapy assessed in the "on" fluctuations and dyskinesias (0-23). Each subsection included subscales that ranged from 0 (best possible outcome) to 1 or 4 (worst possible outcome), with the total score of subsection equaling the sum of the scores of the subscales and the overall UPDRS score equaling the sum of the scores of the 4 subsections (higher score indicating more severe Parkinson's Disease).

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

Subjects and/or caregiver completed a diary recording their motor state and dyskinesia symptoms over the course of the day before and at the end of study drug dosing on 3 consecutive days leading up to Baseline and Day 70. An entry was made every 30 minutes whether they were in the "on" state experiencing troubling dyskinesias or "off" state. The "on" state reflected recovery of control of a particular Parkinsonian feature that readily responded to each dose of levodopa, while the "off" state reflected the re-emergence of that feature. Troublesome dyskinesias were unintentional movements that occurred while in the "on" state and which interfered with activities or caused discomfort to any extent.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

Subjects and/or caregiver completed a diary recording their motor state and dyskinesia symptoms over the course of the day before and at the end of study drug dosing on 3 consecutive days leading up to Baseline and Day 70. An entry was made every 30 minutes whether they were in the "on" state experiencing troubling dyskinesias or "off" state. The "on" state reflected recovery of control of a particular Parkinsonian feature that readily responded to each dose of levodopa, while the "off" state reflected the re-emergence of that feature. Troublesome dyskinesias were unintentional movements that occurred while in the "on" state and which interfered with activities or caused discomfort to any extent.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

Subjects and/or caregiver completed a diary recording their motor state and dyskinesia symptoms over the course of the day before and at the end of study drug dosing on 3 consecutive days leading up to Baseline and Day 70. An entry was made every 30 minutes whether they were in the "on" state experiencing troubling dyskinesias or "off" state. The "on" state reflected recovery of control of a particular Parkinsonian feature that readily responded to each dose of levodopa, while the "off" state reflected the re-emergence of that feature. Troublesome dyskinesias were unintentional movements that occurred while in the "on" state and which interfered with activities or caused discomfort to any extent.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

The Goetz/Rush scale was used to rate severity during performance of tasks intended to elicit dyskinesias, and provided an objective rating of dyskinesias during activities of daily living.The tasks included a sitting exercise, mental calculations, drinking, dressing, and walking. A 5-point scale was used: 0=absent; 1=minimal severity, no interference with voluntary motor acts; 2=dyskinesias, may impair voluntary movements but the subject was capable of efficiently completing the motor task; 3=intense dyskinesias, interference with movement control and completion of the motor task was greatly limited; 4= violent dyskinesias, incompatible with the completion of the motor task. A lower score indicated less difficulty performing the tasks.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

Subjects and/or caregiver completed a diary recording their motor state and dyskinesia symptoms over the course of the day before and at the end of study drug dosing on 3 consecutive days leading up to Baseline and Day 70. An entry was made every 30 minutes whether they were in the "on" state experiencing troubling dyskinesias or "off" state. The "on" state reflected recovery of control of a particular Parkinsonian feature that readily responded to each dose of levodopa, while the "off" state reflected the re-emergence of that feature. Troublesome dyskinesias were unintentional movements that occurred while in the "on" state and which interfered with activities or caused discomfort to any extent.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

Subjects and/or caregiver completed a diary recording their motor state and dyskinesia symptoms over the course of the day before and at the end of study drug dosing on 3 consecutive days leading up to Baseline and Day 70. An entry was made every 30 minutes whether they were in the "on" state experiencing troubling dyskinesias or "off" state. The "on" state reflected recovery of control of a particular Parkinsonian feature that readily responded to each dose of levodopa, while the "off" state reflected the re-emergence of that feature. Troublesome dyskinesias were unintentional movements that occurred while in the "on" state and which interfered with activities or caused discomfort to any extent.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

Subjects and/or caregiver completed a diary recording their motor state and dyskinesia symptoms over the course of the day before and at the end of study drug dosing on 3 consecutive days leading up to Baseline and Day 70. An entry was made every 30 minutes whether they were in the "on" state experiencing troubling dyskinesias or "off" state. The "on" state reflected recovery of control of a particular Parkinsonian feature that readily responded to each dose of levodopa, while the "off" state reflected the re-emergence of that feature. Troublesome dyskinesias were unintentional movements that occurred while in the "on" state and which interfered with activities or caused discomfort to any extent.

Safety Population. Change from Baseline only reflect participants who completed the assessment at Baseline and Day 70.

The disability of dyskinesia was determined from question 33 (part 4) of the UPDRS assessment. It asks how disabling are the dyskinesias, and uses a 5-part scale: 0=Not disabling, 1=MIldly disabling, 2=Moderately disabling, 3=Severely disabling, 4=Completely disabling. Lower scores represented more normal functioning.

Safety Population

The duration of dyskinesia was determined from question 32 (part 4) of the UPDRS assessment. It asks what proportion of the waking day are dyskinesias present, and uses a 5-part scale: 0 = None, 1 = 1-25% of day, 2 = 26-50% of day, 3 = 51-75% of day, 4 = 76-100% of day. Lower scores represented more normal functioning.

Safety Population

Treatment-emergent Adverse Events (TEAEs) were defined as those adverse events (AEs) that started on or after the first dose of study medication until the end of the study. Information on any AEs were recorded throughout the study after informed consent had been signed and included abnormal clinical laboratory tests, vital sign measurements and physical examinations. Note: Safety/tolerability info captured in Adverse Event section.

Safety Population was the primary population for analysis defined as all subjects who completed the Baseline Phase and who received at least 1 dose of double-blind study medication.