A Study to Evaluate the Safety and Tolerability of ABBV-951 in Subjects With Parkinson's Disease (PD)

Parkinson's Disease (PD) Clinical Trial

Official title:

A 52-Week, Open-label, Single-arm Study to Evaluate the Safety and Tolerability of 24-hour Daily Exposure of Continuous Subcutaneous Infusion of ABBV-951 in Subjects With Parkinson's Disease

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03781167
• Other study ID #: M15-741
• Secondary ID: 2018-002144-85
• Status: Completed
• Phase: Phase 3
• Start date: April 29, 2019
• Est. completion date: August 17, 2022

Study information

• Verified date: September 2023
• Source: AbbVie
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this study was to assess the safety and tolerability of ABBV-951 (Foslevodopa/Foscarbidopa) in participants with Parkinson's disease (PD). This was a single-arm study with preplanned analyses conducted by dose subgroup (Low Dose or High Dose) based on the modal total daily dose (most frequent dose) over the treatment period.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 244
• Est. completion date: August 17, 2022
• Est. primary completion date: August 17, 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 30 Years and older

Eligibility

Inclusion Criteria:

• Participants with diagnosis of idiopathic Parkinson's Disease (PD) that is levodopa-responsive
• Participants must be judged by the investigator to be inadequately controlled by current therapy, have recognizable/identifiable "Off" and "On" states (motor fluctuations), and have a minimum of 2.5 hours of "Off" time per day

Exclusion Criteria:

• Participant is cognitively impaired and is not able to safely and effectively manage the drug delivery system and the diaries and is not able to adhere to the study
• Participant is considered by the investigator to be an unsuitable candidate to receive ABBV-951 for any reason

Related Conditions & MeSH terms

• Parkinson Disease
• Parkinson's Disease (PD)

Intervention

Drug:
• ABBV-951
Solution for continuous subcutaneous infusion (CSCI)

Locations

Country	Name	City	State
Australia	Royal Adelaide Hospital /ID# 207634	Adelaide	South Australia
Australia	Concord Repatriation General Hospital /ID# 207628	Concord	New South Wales
Australia	Alfred Health /ID# 207632	Melbourne	Victoria
Australia	Perron Institute /ID# 207627	Nedlands	Western Australia
Australia	Westmead Hospital /ID# 207633	Westmead	New South Wales
Belgium	AZ Sint-Jan Brugge /ID# 208178	Brugge
Belgium	Universitair Ziekenhuis Leuven /ID# 209058	Leuven	Vlaams-Brabant
Belgium	Groupe Sante CHC - Clinique du MontLegia /ID# 208177	Liege
Canada	University of Calgary - Movement Disorders Clinic /ID# 207342	Calgary	Alberta
Canada	Centre de Recherche St-Louis /ID# 207344	Quebec City	Quebec
Denmark	Aarhus University Hospital /ID# 207668	Aarhus N	Midtjylland
Denmark	Bispebjerg and Frederiksberg Hospital /ID# 207669	Copenhagen NV	Hovedstaden
Denmark	Odense University Hospital /ID# 207871	Odense C	Syddanmark
Germany	Kliniken Beelitz GmbH /ID# 208600	Beelitz-Heilstaetten
Germany	InnKlinikum Haag /ID# 208601	Haag
Germany	Universitaetsklinikum Ulm /ID# 208602	Ulm	Baden-Wuerttemberg
Italy	IRCCS Centro Neurolesi Bonino Pulejo /ID# 207975	Messina
Italy	Fondazione IRCCS Istituto Neurologico Carlo Besta /ID# 207955	Milan
Italy	Azienda Ospedaliera di Padova /ID# 208077	Padova
Japan	National Hospital Organization Asahikawa Medical Center /ID# 210914	Asahikawa-shi	Hokkaido
Japan	Juntendo University Hospital /ID# 210915	Bunkyo-ku	Tokyo
Japan	National Center of Neurology and Psychiatry /ID# 210911	Kodaira-shi	Tokyo
Japan	National Hospital Organization Utano National Hospital /ID# 210912	Kyoto-shi	Kyoto
Japan	Osaka University Hospital /ID# 210913	Suita-shi	Osaka
Netherlands	St. Antonius Ziekenhuis /ID# 208529	Nieuwegein
Netherlands	Erasmus Medisch Centrum /ID# 208168	Rotterdam	Zuid-Holland
Russian Federation	City Clinical Hospital #40 /ID# 216301	Sestroretsk	Sankt-Peterburg
Russian Federation	Academician I.P. Pavlov First St. Petersburg State Medical University /ID# 216303	St. Petersburg	Sankt-Peterburg
Spain	Hospital Universitario A Coruna - CHUAC /ID# 212147	A Coruna
Spain	Hospital Santa Creu i Sant Pau /ID# 208240	Barcelona
Spain	Hospital General Universitario de Elche /ID# 209777	Elche	Alicante
Spain	Hospital Universitario Virgen de las Nieves /ID# 208242	Granada
Spain	Hospital Universitario de Bellvitge /ID# 209539	L'Hospitalet de Llobregat	Barcelona
Spain	Hospital Universitario Ramon y Cajal /ID# 208241	Madrid
Spain	Hospital Universitario Virgen del Rocio /ID# 208239	Sevilla
Sweden	Sahlgrenska University Hospital /ID# 207718	Gothenburg	Vastra Gotalands Lan
Sweden	Skane University Hospital Lund /ID# 207811	Lund	Skane Lan
Sweden	Centrum for neurologi /ID# 207716	Stockholm	Stockholms Lan
United Kingdom	NHS Tayside /ID# 209242	Dundee	Scotland
United Kingdom	King's College Hospital NHS Foundation Trust /ID# 208413	London
United Kingdom	University Hospital Plymouth NHS Trust /ID# 208447	Plymouth
United States	University of Colorado Hospital /ID# 207968	Aurora	Colorado
United States	University of Alabama at Birmingham - Main /ID# 207996	Birmingham	Alabama
United States	Parkinson's Disease and Movement Disorders Center of Boca Raton /ID# 207677	Boca Raton	Florida
United States	Massachusetts General Hospital /ID# 207993	Boston	Massachusetts
United States	Northwestern University Feinberg School of Medicine /ID# 208812	Chicago	Illinois
United States	University of Missouri /ID# 209043	Columbia	Missouri
United States	Neurology Consultants of Dallas - LBJ Fwy /ID# 207619	Dallas	Texas
United States	The Parkinson's & Movement Disorder Institute - Fountain Valley /ID# 216126	Fountain Valley	California
United States	Prisma Health Cancer Institute-Faris Road /ID# 207650	Greenville	South Carolina
United States	Baylor College of Medicine /ID# 207620	Houston	Texas
United States	Indiana Clinical Research Cent /ID# 207952	Indianapolis	Indiana
United States	Univ Kansas Med Ctr /ID# 208963	Kansas City	Kansas
United States	Booth Gardner Parkinson's Care Center /ID# 208026	Kirkland	Washington
United States	Dartmouth-Hitchcock Medical Center /ID# 207972	Lebanon	New Hampshire
United States	University of Kentucky Chandler Medical Center /ID# 207603	Lexington	Kentucky
United States	Medical College of Wisconsin /ID# 207999	Milwaukee	Wisconsin
United States	Legacy Medical Group - Neurology /ID# 208031	Portland	Oregon
United States	Wake Radiology UNC REX Healthcare - Raleigh Office /ID# 209784	Raleigh	North Carolina
United States	Central Texas Neurology Consul /ID# 216918	Round Rock	Texas
United States	Washington University-School of Medicine /ID# 207525	Saint Louis	Missouri
United States	Health Partners /ID# 207950	Saint Paul	Minnesota
United States	Univ Texas HSC San Antonio /ID# 208958	San Antonio	Texas
United States	Inland Northwest Research /ID# 208122	Spokane	Washington
United States	Banner Sun Health Res Inst /ID# 208811	Sun City	Arizona

Sponsors (1)

Lead Sponsor	Collaborator
AbbVie

Countries where clinical trial is conducted

United States,  Australia,  Belgium,  Canada,  Denmark,  Germany,  Italy,  Japan,  Netherlands,  Russian Federation,  Spain,  Sweden,  United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of Participants With Adverse Events	An adverse event (AE) is defined as any untoward medical occurrence in a patient or clinical investigation participant administered a pharmaceutical product which does not necessarily have a causal relationship with this treatment. The investigator assesses the relationship of each event to the use of study drug. 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. Treatment-emergent adverse events/treatment-emergent serious adverse events (TEAEs/TESAEs) are defined as any event that began or worsened in severity on or after the first dose of study drug.	From first dose of study drug until 30 days following last dose of study drug (up to 480 days)
Primary	Number of Participants With Adverse Events of Special Interest	Treatment emergent adverse events of special interest are defined as any adverse event of infusion site infections, infusion site reactions, hallucinations/psychosis, falls and associated injuries, polyneuropathy (peripheral neuropathy), weight loss, or somnolence from the first dose of study drug until 30 days following last dose of study drug.	From first dose of study drug until 30 days following last dose of study drug (up to 480 days)
Primary	Number of Participants With Numeric Grade Equal to or Higher Than 5 and With Letter Grade Equal to or Higher Than D on the Infusion Site Evaluation Scale	Skin tolerability was assessed using the Infusion Site Evaluation Scale, a 2-part numeric (0-7) and letter (A-G) grade scale, where a notable skin reaction is defined as a reaction with a numeric grade of 6 or 7 or a letter grade of D, E, F, or G. Any observation of infusion site reaction with irritation criteria > 2 or > C was recorded as an adverse event (AE).	Day 1, Day 2, Week 1, Week 2, Week 3, Week 4, Week 6, Week 13, Week 26, Week 39, and Week 52
Primary	Hematocrit (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Hemoglobin (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Red Blood Cell (RBC) Count (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	White Blood Cell (WBC) Count (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Neutrophils (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Lymphocytes (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Monocytes (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Absolute Platelet Count (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Mean Corpuscular Hemoglobin (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Mean Corpuscular Volume Concentration (MCHC) (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Prothrombin Time (PT) (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Activated Partial Thromboplastin Time (Hematology): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Blood Urea Nitrogen (BUN) (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Creatinine (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Creatine Phosphokinase (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Total Bilirubin (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Serum Alanine Aminotransferase (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Serum Aspartate Aminotransferase (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Serum Lactate Dehydrogenase (LDH) (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Gamma-glutamyl Transferase (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Alkaline Phosphatase (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Sodium (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Potassium (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Calcium (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Inorganic Phosphorus (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Uric Acid (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Total Cholesterol (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Albumin (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Glucose (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Sodium Bicarbonate/CO2 (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Magnesium (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Creatinine Clearance (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Homocysteine (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, and 52
Primary	Vitamin B6 (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, and 52
Primary	Vitamin B12 (Clinical Chemistry): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, and 52
Primary	pH (Urinalysis): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Specific Gravity (Urinalysis): Change From Baseline to End of Study	Samples for clinical laboratory tests were collected at study visits, and a certified central laboratory was used to process the samples and provide results.	Baseline, Weeks 6, 26, 39, and 52
Primary	Orthostatic Systolic Blood Pressure (Vital Signs): Change From Baseline to End of Study	Orthostatic blood pressure was measured after the participant had been supine (lying down with their face up) for at least 5 minutes and then, after the participant had been standing for 2 minutes. When vital sign measurements were scheduled at the same time as a blood collection, vital sign measurements were obtained prior to blood collection.	Baseline, Weeks 1, 6, 26, and 52 (orthostatic and standing); Baseline, Weeks 2, 4, 13, and 39 (supine)
Primary	Orthostatic Diastolic Blood Pressure (Vital Signs): Change From Baseline to End of Study	Orthostatic blood pressure was measured after the participant had been supine (lying down with their face up) for at least 5 minutes and then, after the participant had been standing for 2 minutes. When vital sign measurements were scheduled at the same time as a blood collection, vital sign measurements were obtained prior to blood collection.	Baseline, Weeks 1, 6, 26, and 52 (orthostatic and standing); Baseline, Weeks 2, 4, 13, and 39 (supine)
Primary	Orthostatic Pulse Rate (Vital Signs): Change From Baseline to End of Study	Orthostatic pulse rate was measured after the participant had been supine (lying down with their face up) for at least 5 minutes and then, after the participant had been standing for 2 minutes. When vital sign measurements were scheduled at the same time as a blood collection, vital sign measurements were obtained prior to blood collection.	Baseline, Weeks 1, 6, 26, and 52 (orthostatic and standing); Baseline, Weeks 2, 4, 13, and 39 (supine)
Primary	Electrocardiogram (ECG) Mean Heart Rate: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Primary	Electrocardiogram (ECG) Aggregate PR Interval: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Primary	Electrocardiogram (ECG) Aggregate QRS Duration: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Primary	Electrocardiogram (ECG) Aggregate QT Interval: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Primary	Electrocardiogram (ECG) Aggregate QTcB Interval: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Primary	Electrocardiogram (ECG) Aggregate QTcF Interval: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Primary	Electrocardiogram (ECG) Aggregate RR Interval: Change From Baseline to End of Study	12-lead electrocardiograms (ECGs) were recorded at study visits after the participant had been supine for at least 5 minutes. Participants were instructed to remain stationary (no talking, laughing, deep breathing, sleeping, or swallowing) for approximately 10 seconds during the ECG recording. When an ECG was recorded at a time near that of a blood collection, the ECG was obtained prior to the blood collection. ECGs on Day 1 were recorded after initiation of the continuous subcutaneous infusion (CSCI) of ABBV-951 prior to the end of the study visit.	Baseline, Day 1 (postdose), Weeks 6 and 52
Secondary	Average Daily Normalized "Off" Time: Change From Baseline to End of Study	Upon awakening and every 30 minutes during their normal waking time, participants recorded their state in the Parkinson's Disease Diary (PD Diary) for 2 consecutive days prior to study visits.; "Off" time is defined as periods of poor mobility, tremor, slowness, and stiffness. The daily "On" and "Off" times were normalized to a typical waking day (16 hours) to account for different sleep patterns across participants. When "Off" was the first morning symptom upon awakening, this was considered morning akinesia in this study.; Baseline value is defined as the average of normalized "Off" time collected over the 2 PD Diary days before the Enrollment visit. Negative changes from Baseline indicate improvement.	Baseline, Weeks 1, 6, 13, 26, 39, and 52
Secondary	Average Daily Normalized "On" Time With Troublesome Dyskinesia: Change From Baseline to End of Study	Upon awakening and every 30 minutes during their normal waking time, participants recorded their state in the Parkinson's Disease Diary (PD Diary) for 2 consecutive days prior to study visits.; "On" time is defined as periods of good motor symptom control. The daily "On" and "Off" times were normalized to a typical waking day (16 hours) to account for different sleep patterns across participants.; Baseline value is defined as the average of normalized "On" time with troublesome dyskinesia collected over the 2 PD Diary days before the Enrollment visit. Negative changes from Baseline indicate improvement.	Baseline, Weeks 1, 6, 13, 26, 39, and 52
Secondary	Average Daily Normalized "On" Time Without Troublesome Dyskinesia: Change From Baseline to End of Study	Upon awakening and every 30 minutes during their normal waking time, participants recorded their state in the Parkinson's Disease Diary (PD Diary) for 2 consecutive days prior to study visits.; "On" time is defined as periods of good motor symptom control. The daily "On" and "Off" times were normalized to a typical waking day (16 hours) to account for different sleep patterns across participants.; Baseline value is defined as the average of normalized "On" time without troublesome dyskinesia collected over the 2 PD Diary days before the Enrollment visit. Positive changes from Baseline indicate improvement.	Baseline, Weeks 1, 6, 13, 26, 39, and 52
Secondary	Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part I Score: Change From Baseline to End of Study	The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is an investigator-used rating tool to follow the longitudinal course of Parkinson's Disease (PD). Part I assesses the participant's non-motor aspects of experiences of daily living (nM-EDL) with 13 questions. (The numeric score for each question is between 0-4; 0=Normal,1=Slight,2=Mild,3=Moderate,4=Severe). Part I scores range from 0 to 52, with higher scores indicating more severe symptoms of PD. Negative changes from Baseline indicate improvement.	Baseline, Day 2, Weeks 1, 2, 3, 4, 6, 13, 26, 39, and 52
Secondary	Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part II Score: Change From Baseline to End of Study	The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is an investigator-used rating tool to follow the longitudinal course of Parkinson's Disease (PD). Part II assesses the participant's motor experiences of daily living (M-EDL) with 13 questions. (The numeric score for each question is between 0-4; 0=Normal,1=Slight,2=Mild,3=Moderate,4=Severe). Part II scores range from 0 to 52, with higher scores indicating more severe symptoms of PD. Negative changes from Baseline indicate improvement.	Baseline, Day 2, Weeks 1, 2, 3, 4, 6, 13, 26, 39, and 52
Secondary	Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III Score: Change From Baseline to End of Study	The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is an investigator-used rating tool to follow the longitudinal course of Parkinson's Disease (PD). Part III assesses the participant's motor examination (including Hoehn and Yahr stage) with 33 questions. (The numeric score for each question is between 0-4; 0=Normal,1=Slight,2=Mild,3=Moderate,4=Severe). Part III scores range from 0 to 132, with higher scores indicating more severe symptoms of PD. Negative changes from Baseline indicate improvement.	Baseline, Day 2, Weeks 1, 2, 3, 4, 6, 13, 26, 39, and 52
Secondary	Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part IV Score: Change From Baseline to End of Study	The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is an investigator-used rating tool to follow the longitudinal course of Parkinson's Disease (PD). Part IV assesses the participant's motor complications with 6 questions. (The numeric score for each question is between 0-4; 0=Normal,1=Slight,2=Mild,3=Moderate,4=Severe). Part IV scores range from 0 to 24, with higher scores indicating more severe symptoms of PD. Negative changes from Baseline indicate improvement.	Baseline, Day 2, Weeks 1, 2, 3, 4, 6, 13, 26, 39, and 52
Secondary	Sleep Symptoms as Assessed by the Parkinson's Disease Sleep Scale-2 (PDSS-2) Total Score: Change From Baseline to End of Study	The PDSS-2 consists of 15 questions that evaluate motor and non-motor symptoms at night and upon wakening, as well as disturbed sleep grouped into 3 domains: motor symptoms at night (5 items), Parkinson's Disease (PD) symptoms at night (5 items), and disturbed sleep (5 items). The frequency is assessed for the 15 sleep problems based on a 5-point Likert-type scale (ranging from 0 [never] to 4 [very often] with the exception of Question 1 score ranging from 0 [very often] to 4 [never]). Scores are calculated for each of the 3 domains as well as a total score. The PDSS-2 domain scores range from 0 to 20 and the total score is a sum of the 3 domains and ranges from 0 to 60. Higher scores indicate higher frequency and more severe impact of PD on sleep. Negative changes indicate improvement from Baseline.	Baseline, Weeks 6, 13, 26, 39, and 52
Secondary	Quality of Life Assessed by the Parkinson's Disease Questionnaire-39 Items (PDQ-39) Summary Index Score: Change From Baseline to End of Study	The Parkinson's Disease Questionnaire (PDQ-39) is a disease-specific instrument designed to measure aspects of health that are relevant to participants with Parkinson's Disease (PD), and which may not be included in general health status questionnaires. Each item is scored on the following 5-point scale: 0 = never, 1 = occasionally, 2 = sometimes, 3 = often, 4 = always (or cannot do at all, if applicable). Higher scores are consistently associated with more severe symptoms of the disease such as tremors and stiffness. The results can be presented in either domain scores or as a summary index score. The full range of the PDQ-39 summary index score is from 0 (no patient-related symptoms/quality of life unaffected) to 100 (highest patient-related symptoms/low quality of life). Negative changes indicate improvement from Baseline.	Baseline, Weeks 6, 13, 26, 39, and 52
Secondary	The EuroQol 5-Dimension Questionnaire (EQ-5D-5L) Quality of Life Summary Index: Change From Baseline to End of Study	The EuroQol 5-dimension questionnaire (EQ-5D-5L) is a standardized non-disease specific instrument for describing and valuing health-related quality of life. The EQ-5D-5L descriptive system comprises 5 dimensions of health (mobility, self -care, usual activities, pain/discomfort, and anxiety/depression) to describe the participant's current health state. Each dimension comprises 5 levels with corresponding numeric scores, where 1 indicates no problems, and 5 indicates extreme problems. The health status is converted to an index value using the country-specific weighted scoring algorithm for the United States (US). The summary index value for the US ranges from a worst score of -0.109 to a best score of 1. An increase in the EQ-5D-5L total score indicates improvement.	Baseline, Weeks 6, 13, 26, 39, and 52