Study to Assess How ABBV-951 is Absorbed When Administered at Different Subcutaneous Sites of 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 means it affects the brain. This study will evaluate how ABBV-951 is absorbed under the skin of participants with PD when administered to arm, thigh and flank compared to the abdomen. ABBV-951 is an investigational drug being developed for the treatment of PD. Study doctors randomly assign participants to 1 of 4 groups, called treatment arms. Each treatment arm receives ABBV-951 administered in a different order in the arm, high, flank and abdomen. Approximately 12 adult participants over 30 years with a diagnosis of PD will be enrolled in approximately 10 sites in the United States. Participants will receive continuous (24hours/day) subcutaneous infusion of ABBV-951 for 2 consecutive days for each infusion site (arm, thigh, flank and abdomen), for a total duration of treatment up to 12 days. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will be confined at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects and completing questionnaires. Adverse events will be monitored throughout the study.

Official Title
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Parkinson's Disease: A Comparative Study of Levodopa and Carbidopa Bioavailability Following Foslevodopa/Foscarbidopa Infusion at Different Subcutaneous Sites in Parkinson's Disease Patients

Conditions
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Parkinson's Disease

Intervention / Treatment
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* Drug: ABBV-951


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of idiopathic Parkinson's disease (PD) that is Levodopa-responsive. Must be taking a minimum of 400 mg/day of levodopa equivalents (LE) and be judged by the investigator to have motor symptoms inadequately controlled by current therapy. Must have recognizable/identifiable Off and On states (motor fluctuations), and have a minimum daily average of 2.5 hours of Off time (with a minimum of 2 hours of Off time each day). Exclusion Criteria: - History of significant skin conditions or disorders (e.g., psoriasis, atopic dermatitis, etc.) or evidence of recent sunburn, acne, scar tissue, tattoo, open wound, branding, or colorations that in the investigator's opinion would interfere with the infusion of the study drug or could interfere with study assessments.

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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Arm 1: ABBV-951<br>Participants will receive ABBV-951 for 2 consecutive days in the abdomen (Period 1), flank (Period 2), arm (Period 3) and thigh (Period 4). | Drug: ABBV-951<br>* Continuous Subcutaneous Infusion (CSCI)<br>* Other names: Foslevodopa/foscarbidopa;|
| Experimental: Arm 2: ABBV-951<br>Participants will receive ABBV-951 for 2 consecutive days in the arm (Period 1), abdomen (Period 2), thigh (Period 3) and flank (Period 4). | Drug: ABBV-951<br>* Continuous Subcutaneous Infusion (CSCI)<br>* Other names: Foslevodopa/foscarbidopa;|
| Experimental: Arm 3: ABBV-951<br>Participants will receive ABBV-951 for 2 consecutive days in the thigh (Period 1), arm (Period 2), flank (Period 3) and abdomen (Period 4). | Drug: ABBV-951<br>* Continuous Subcutaneous Infusion (CSCI)<br>* Other names: Foslevodopa/foscarbidopa;|
| Experimental: Arm 4: ABBV-951<br>Participants will receive ABBV-951 for 2 consecutive days in the flank (Period 1), thigh (Period 2), abdomen (Period 3) and arm (Period 4). | Drug: ABBV-951<br>* Continuous Subcutaneous Infusion (CSCI)<br>* Other names: Foslevodopa/foscarbidopa;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum Observed Plasma Concentration (Cmax) of Levodopa (LD) | Maximum observed plasma concentration (Cmax) of Levodopa (LD). | Up to 8 Days | 
| Area Under the Plasma Concentration-Time Curve (AUC) for the 24-hour Interval of LD | Area under the plasma concentration-time curve (AUC) for the 24-hour interval of LD. | Up to 8 Days | 
| Minimum Observed Plasma Concentration (Cmin) of LD | Minimum observed plasma concentration (Cmin) of LD. | Up to 8 Days | 
| Degree of Fluctuation (DFL) of LD | DFL = (Cmax-Cmin)/(average plasma concentration). | Up to 8 Days | 
| Swing of LD | Swing = (Cmax-Cmin)/Cmin. | Up to 8 Days | 
| Maximum Observed Plasma Concentration (Cmax) of Carbidopa (CD) | Maximum observed plasma concentration (Cmax) of CD. | Up to 8 Days | 
| Area Under the Plasma Concentration-Time Curve (AUC) for the 24-hour Interval of CD | Area under the plasma concentration-time curve (AUC) for the 24-hour interval of CD. | Up to 8 Days | 
| Minimum Observed Plasma Concentration (Cmin) of CD | Minimum observed plasma concentration (Cmin) of CD. | Up to 8 Days | 
| Degree of Fluctuation (DFL) of CD | DFL = (Cmax-Cmin)/(average plasma concentration). | Up to 8 Days | 
| Swing of CD | Swing = (Cmax-Cmin)/Cmin. | Up to 8 Days | 

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