Extension Study To Evaluate Safety And Tolerability Of 24-Hour Daily Exposure Of Continuous Subcutaneous Infusion of ABBV-951 In Adult Participants With Parkinson's Disease

Study Overview
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Brief Summary
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Parkinson's disease (PD) is a neurological condition, which affects the brain. PD gets worse over time, but how quickly it progresses varies a lot from person to person. Some symptoms of PD are tremors, stiffness, and slowness of movement. The purpose of this study is to continue testing whether ABBV-951 is safe, effective, and tolerable in participants with Parkinson's disease after completion of the parent study M15-741. ABBV-951 is an investigational (unapproved) drug containing levodopa phosphate/carbidopa phosphate (LDP/CDP) given as infusion under the skin for the treatment of Parkinson's Disease. Participants who have successfully completed M15-741 study will immediately enter this study's treatment period to continue receiving ABBV-951. Adult participants with advanced PD will be enrolled. Approximately 130 adult participants will be enrolled in the study at approximately 65 sites worldwide. Participants will receive continuous subcutaneous infusion (CSCI) of ABBV-951 for 24 hours daily during the Primary Treatment Period and during the optional Extended Treatment Period. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular clinic visits and have remote assessments completed via phone calls during the course of the study. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects, and completing questionnaires.

Official Title
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An Open-label Extension of Study M15-741 to Evaluate the Safety and Tolerability of 24-hour Daily Exposure of Continuous Subcutaneous Infusion of ABBV-951 in Subjects With Parkinson's Disease

Conditions
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Parkinson's Disease (PD)

Intervention / Treatment
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* Drug: ABBV-951


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants who have Parkinson's Disease and who have successfully completed the parent study M15-741. Participants willing and able to comply with procedures required in the protocol. Exclusion Criteria: - Participants, if judged by the investigator to be unsuitable candidates to continue to receive ABBV-951 for any reason.

Ages Eligible for Study
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Minimum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ABBV-951<br>Participants will receive ABBV-951 solution by continuous subcutaneous infusion (CSCI), at the discretion of the investigator, for up to 96 weeks. | Drug: ABBV-951<br>* Solution for continuous subcutaneous infusion (CSCI).<br>* Other names: Foslevodopa;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With Adverse Events (AE) | An AE is defined as any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and which does not necessarily have a causal relationship with the treatment. The investigator assesses the relationship of each event to the use of the study drug or device as either reasonable possibility or no reasonable possibility. A serious adverse event (SAE) is an event that results in death, is life-threatening, requires or prolongs hospitalization, results in a congenital anomaly, persistent or significant disability/incapacity or is an important medical event that, based on medical judgment, may jeopardize the participant and may require medical or surgical intervention to prevent any of the outcomes listed above. Adverse Events of Special Interest (AESI) - polyneuropathy, weight loss, hallucinations/psychosis, and somnolence will be monitored throughout the study. | Up To Week 96 | 
| Percentage Of Participants With Numeric Grade Equal To Or Higher Than 5 On The Infusion Site Evaluation Scale | The Infusion Site Evaluation Scale will be used to assess infusion sites. Infusion Site Evaluation Scale is an eight-point numeric scale used to assess irritation at the infusion site area (0 being no evidence of irritation and 7 being strong reaction spreading beyond the test site). | Up To Week 96 | 
| Percentage Of Participants With Letter Grade Equal To Or Higher Than D On The Infusion Site Evaluation Scale | The Infusion Site Evaluation Scale will be used to assess infusion sites. Infusion Site Evaluation Scale is an A to G letter grade scale, used to assess irritation at the infusion site area (A being no finding to G being Small petechial erosions and/or scabs). | Up To Week 96 | 
| Change in Clinical Laboratory Test Data | Number of participants with clinically significant change from baseline in laboratory parameters (hematology, biochemistry, coagulation, and urinalysis) will be reported throughout the study. | Up To Week 96 | 
| Change in Vital Signs Measurements | Number of participants with clinically significant change from baseline in vital signs will be reported throughout the study. | Up To Week 96 | 
| Change From Baseline in Electrocardiograms (ECGs) | Change from baseline in 12-lead ECGs on heart rate, RR interval, PR interval, QRS duration, and QT interval will be monitored throughout the study. | Up To Week 96 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average Normalized Daily Off Time | Average normalized daily Off Time (Hours) is assessed based on Parkinson's Disease (PD) Diary. | Up To Week 96 | 
| Average Normalized Daily On Time | Average normalized daily On time is assessed based on Parkinson's Disease (PD) Diary. | Up To Week 96 | 
| Parkinson's Disease (PD) Symptoms Measurement | PD symptoms will be assessed by the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Parts I-IV. The MDS-UPDRS is an investigator-used rating tool to follow the longitudinal course of Parkinson's Disease (PD) with scores ranging from 0 to 236 with 236 representing the worst disability, and 0 representing no disability. | Up To Week 96 | 
| Change From Baseline in Quality Of Life Measurement as Assessed by PD Questionnaire-39 (PDQ-39) | Quality of life is assessed by the PD Questionnaire-39 items (PDQ-39). PDQ-39 is a disease-specific instrument designed to measure aspects of health that are relevant to participants with PD, and which may not be included in general health status questionnaires. Each item is scored on a 5-point scale. | Up To Week 96 | 
| Change From Baseline in Health-related Quality Of Life Measurement as Assessed by EuroQol 5-dimensions questionnaire (EQ-5D-5L) | Health-related quality of life is assessed by the EuroQol 5-dimensions questionnaire (EQ-5D-5L). EQ-5D-5L is a standardized instrument that consists of 2 parts: the EQ-5D descriptive system and the EQ visual analogue-scale (EQVAS). | Up To Week 96 | 
| Cognitive Impairment Measurement | Cognitive impairment is assessed by the Mini-Mental State Examination (MMSE). MMSE is used to assess orientation, attention, immediate and short term recall, language, and ability to follow simple verbal and written commands. The test consists of five sections (orientation, registration, attention-calculation, recall, and language) and results in a total possible score of 0 to 30, with higher scores indicating better function. | Up To Week 96 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Parkinson's Disease (PD), ABBV-951, Levodopa/Carbidopa (LD/CD), Levodopa Phosphate/Carbidopa Phosphate (LDP/CDP)