TEMPO-4

Key Inclusion Criteria:

Rollover participants are eligible for the study if they met the following inclusion
criteria:

- Participants who complete the 27-week double-blind Treatment Period of Trial
CVL-751-PD-001 (NCT04201093) or Trial CVL-751 PD-003 (NCT04542499) or the 27-week
double-blind Treatment Period and 10-day Safety/Withdrawal Assessment Period of
Trial CVL-751-PD-002 (NCT04223193) and enter this trial within 72 hours after
completing the last trial visit in the double-blind trial. Rollover participants
from Trial CVL-751-PD-003 must continue to use levodopa/carbidopa (or
levodopa/benserazide) for the duration of the trial.

- Sexually active men or women of childbearing potential must agree to use acceptable
(at minimum) or highly effective birth control, or remain abstinent during the trial
and for 4 weeks after the last dose of trial treatment.

- Participants who are capable of giving signed informed consent, which includes
compliance with the requirements and restrictions listed in the ICF and in the
protocol.

- Participants who are willing and able to refrain from any PD medications that are
not permitted by the protocol (including dopaminergic agents) throughout
participation in the trial.

- Participant who, in the judgement of the investigator, demonstrated adequate
compliance with the IMP and protocol requirements in the double-blind trial.

Key Exclusion criteria:

Rollover participants are excluded from the trial if any of the following met:

- Participants who do not enroll in this open-label trial within 72 hours after
completing the last trial visit in the double-blind trial

- Participants who answer "yes" on the C-SSRS Suicidal Ideation Item 4 or Item 5
(Active Suicidal Ideation with Some Intent to Act, Without Specific Plan, or Active
Suicidal Ideation with Specific Plan and Intent) and whose most recent episode
meeting the criteria for C-SSRS Item 4 or Item 5 occurred within the last 6 months,
OR Participants who answer "yes" on any of the 5 C-SSRS Suicidal Behavior Items
(actual attempt, interrupted attempt, aborted attempt, preparatory acts, or
behavior) and whose most recent episode meeting the criteria for any of these 5
C-SSRS Suicidal Behavior Items occurred within the last 2 years, OR Participants
who, in the opinion of the investigator, present a serious risk of suicide.

- Participants who had previously been enrolled in this open-label trial and had
subsequently withdrawn.