A Study to Evaluate the Efficacy, Safety, Tolerability, and Pharmacokinetics of UCB0022 in Study Participants With Advanced Parkinson's Disease

Inclusion Criteria:

• Study participant must be 35 to 85 years of age (inclusive) at the time of signingthe informed consent form (ICF)

• Study participant is diagnosed with Parkinson's disease (PD) (based on the UnitedKingdom Parkinson's Disease Society Brain Bank Diagnostic criteria performed at theScreening Visit) and diagnosed ≥5 years before the Screening Visit (based onhistorical medical- information documented by the investigator)

• Study participant has significant daily motor fluctuations

• Study participant is able to complete a Hauser PD symptoms diary and differentiatebetween the ON and OFF states

• Study participant is responsive to levodopa and currently receiving treatment withoral daily doses of levodopa combination (levodopa/carbidopa orlevodopa/benserazide) with or without oral adjunctive antiparkinsonian therapies (based on historical clinical data)

• Study participant has disease severity Stages I-III (modified Hoehn and Yahrstaging) during ON state

• Study participant agrees to not post personal medical data or information related tothe study on social media until study completion

• Study participant has body weight ≥45 kg and body mass index within 18 to 30 kg/m^2 (inclusive)

• Study participant may be male or female:

1. A male study participant must agree to use contraception during the TreatmentPeriod and for at least 2 weeks after the last dose of study treatment andrefrain from donating sperm during this period

2. A female study participant must not be a woman of childbearing potential (WOCBP)

Exclusion Criteria:

• Study participant is diagnosed with any form of Parkinsonism other than idiopathicPD (eg, atypical or secondary Parkinsonism)

• Study participant is diagnosed with dementia or has important cognitive dysfunction,as determined by Montreal Cognitive Assessment (MoCA) <23 at screening

• Study participant has a history of neurosurgical intervention for PD (including DBS,thalamotomy, and experimental cell therapy or gene therapy)

• Participant has a severe peak dose or biphasic dyskinesia at screening, defined byMovement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) items 4.2 score 4 or as per investigator opinion

• Participant has a history of major depression or psychotic disorder or any otherpsychiatric condition within the past 5 years, that, as per investigator opinion,could jeopardize or would compromise the study participant's ability to participatein the study

• Study participant has a history of narrow angle glaucoma

• Study participant has a history of melanoma

• Study participant has current untreated hypertension

• Study participant has a history of hypertensive crisis and/or hypertensiveencephalopathy, unless the underlying cause was unequivocally identified and hasbeen removed

• Study participant has orthostatic hypotension requiring medication or a currenthistory of "clinically significant" orthostatic hypotension as per theinvestigator's opinion (eg, recurrent orthostatic presyncope or syncope)

• Study participant has a history over the past 12 months or between the Screening andBaseline Visits of any clinically significant arrythmia, myocardial infarction,stroke, transient ischemic attack, moderate or severe congestive heart failure (either New York Heart Association Class III or IV or known ejection fraction <40%)