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

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

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.

Study Overview

• Status: Completed
• Conditions: Parkinson's Disease (PD)
• Intervention / Treatment: Drug: ABBV-951

• Study Type: Interventional
• Enrollment (Actual): 130
• Phase: Phase 3

Contacts and Locations

Study Locations

• Australia
  • New South Wales
    • Concord, New South Wales, Australia, 2139
      • Concord Repatriation General Hospital /ID# 215943
    • Westmead, New South Wales, Australia, 2145
      • Westmead Hospital /ID# 215941
  • South Australia
    • Adelaide, South Australia, Australia, 5000
      • Duplicate_Royal Adelaide Hospital /ID# 215940
  • Victoria
    • Melbourne, Victoria, Australia, 3004
      • The Alfred Hospital /ID# 215942
  • Western Australia
    • Nedlands, Western Australia, Australia, 6009
      • Perron Institute /ID# 215944
• Belgium
  • Liège, Belgium, 4000
    • Duplicate_Groupe Sante CHC - Clinique du MontLegia /ID# 215685
  • Vlaams-Brabant
    • Leuven, Vlaams-Brabant, Belgium, 3000
      • Universitair Ziekenhuis Leuven /ID# 215684
  • West-Vlaanderen
    • Bruges, West-Vlaanderen, Belgium, 8000
      • Duplicate_Algemeen Ziekenhuis Sint-Jan Brugge /ID# 215686
• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2N 4Z6
      • University of Calgary /ID# 215369
  • Quebec
    • Lévis, Quebec, Canada, G6W 0M5
      • Clinique Neuro Levis /ID# 215371
• Denmark
  • Capital Region
    • Copenhagen NV, Capital Region, Denmark, 2400
      • Bispebjerg and Frederiksberg Hospital /ID# 215391
  • Central Jutland
    • Aarhus, Central Jutland, Denmark, 8200
      • Aarhus Universitetshospital - Skejby /ID# 215392
  • Region Syddanmark
    • Odense, Region Syddanmark, Denmark, 5000
      • Odense University Hospital /ID# 215390
• Germany
  • Beelitz-Heilstätten, Germany, 14547
    • Kliniken Beelitz GmbH /ID# 215403
  • Baden-Wurttemberg
    • Ulm, Baden-Wurttemberg, Germany, 89081
      • Universitaetsklinikum Ulm /ID# 215405
  • Bavaria
    • Haag i.OB, Bavaria, Germany, 83527
      • curiositas ad sanum /ID# 215404
• Italy
  • Messina, Italy, 98124
    • IRCCS Centro Neurolesi Bonino Pulejo /ID# 215422
  • Padova, Italy, 35128
    • Azienda Ospedale-Universita Padova /ID# 215421
• Japan
  • Hokkaido
    • Asahikawa-shi, Hokkaido, Japan, 070-8644
      • National Hospital Organization Asahikawa Medical Center /ID# 218762
  • Osaka
    • Suita-shi, Osaka, Japan, 565-0871
      • Duplicate_Osaka University Hospital /ID# 217415
  • Tokyo
    • Kodaira-shi, Tokyo, Japan, 187-8551
      • National Center of Neurology and Psychiatry /ID# 218763
• Netherlands
  • Utrecht, Netherlands, 3543 AZ
    • St. Antonius Ziekenhuis, Locatie Utrecht /ID# 215396
• Russia
  • Sankt-Peterburg
    • Saint Petersburg, Sankt-Peterburg, Russia, 197101
      • Academician I.P. Pavlov First St. Petersburg State Medical University /ID# 218869
    • Sestroretsk, Sankt-Peterburg, Russia, 197706
      • City Clinical Hospital #40 /ID# 218870
• Spain
  • Barcelona, Spain, 08041
    • Hospital Santa Creu i Sant Pau /ID# 215429
  • Granada, Spain, 18014
    • Hospital Universitario Virgen de las Nieves /ID# 215431
  • Seville, Spain, 41013
    • Hospital Universitario Virgen del Rocio /ID# 215428
  • A Coruna
    • A Coruña, A Coruna, Spain, 15006
      • Complejo Hospitalario Universitario A Coruña /ID# 215426
  • Alicante
    • Elche, Alicante, Spain, 03203
      • Hospital General Universitario de Elche /ID# 215425
  • Barcelona
    • L'Hospitalet de Llobregat, Barcelona, Spain, 08907
      • Hospital Universitari de Bellvitge /ID# 215427
• Sweden
  • Skåne County
    • Lund, Skåne County, Sweden, 224 84
      • Skane University Hospital Lund /ID# 215385
  • Stockholm County
    • Huddinge, Stockholm County, Sweden, 141 57
      • Karolinska Universitetssjukhuset - Huddinge /ID# 215386
  • Västra Götaland County
    • Gothenburg, Västra Götaland County, Sweden, 413 46
      • Sahlgrenska Universitetssjukhuset /ID# 215387
• United Kingdom
  • Devon
    • Plymouth, Devon, United Kingdom, PL6 8DH
      • Derriford Hospital and the Royal Eye Infirmary /ID# 217390
  • Greater London
    • London, Greater London, United Kingdom, SE5 9RS
      • Kings College Hospital NHS Foundation Trust /ID# 217388
  • Scotland
    • Dundee, Scotland, United Kingdom, DD2 1UB
      • NHS Tayside /ID# 217389
• United States
  • Alabama
    • Birmingham, Alabama, United States, 35233
      • University of Alabama at Birmingham - Main /ID# 215597
  • Arizona
    • Sun City, Arizona, United States, 85351
      • Banner Sun Health Research Institute /ID# 215579
  • Colorado
    • Aurora, Colorado, United States, 80045
      • University of Colorado Hospital /ID# 215625
  • Florida
    • Boca Raton, Florida, United States, 33486
      • Parkinson's Disease and Movement Disorders Center of Boca Raton /ID# 215412
  • Indiana
    • Indianapolis, Indiana, United States, 46202
      • Indiana Clinical Research Cent /ID# 216490
  • Kansas
    • Kansas City, Kansas, United States, 66160
      • Univ Kansas Med Ctr /ID# 215624
  • Missouri
    • St Louis, Missouri, United States, 63110
      • Washington University-School of Medicine /ID# 215472
  • New Hampshire
    • Lebanon, New Hampshire, United States, 03756
      • Dartmouth-Hitchcock Medical Center /ID# 216834
  • North Carolina
    • Raleigh, North Carolina, United States, 27612-8106
      • M3 Wake Research - Raleigh /ID# 215596
  • Oregon
    • Portland, Oregon, United States, 97232-2003
      • Legacy Medical Group - Neurology /ID# 215536
  • Texas
    • Houston, Texas, United States, 77030
      • Baylor College of Medicine /ID# 215401
    • Round Rock, Texas, United States, 78681
      • Central Texas Neurology Consul /ID# 217013
    • San Antonio, Texas, United States, 78229-3901
      • Univ Texas HSC San Antonio /ID# 215400
  • Washington
    • Kirkland, Washington, United States, 98034-3029
      • Booth Gardner Parkinson's Care Center /ID# 215535
    • Spokane, Washington, United States, 99202-1342
      • Inland Northwest Research /ID# 215533

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ABBV-951; 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; Solution for continuous subcutaneous infusion (CSCI).; Other Names: Foscarbidopa; Foslevodopa

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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
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
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

Collaborators and Investigators

• Sponsor: AbbVie
• Investigators: Study Director: ABBVIE INC., AbbVie

Study record dates

Study Major Dates

• Study Start (Actual): June 8, 2020
• Primary Completion (Actual): April 17, 2026
• Study Completion (Actual): April 17, 2026

Study Registration Dates

• First Submitted: May 1, 2020
• First Submitted That Met QC Criteria: May 6, 2020
• First Posted (Actual): May 7, 2020

Study Record Updates

• Last Update Posted (Actual): May 13, 2026
• Last Update Submitted That Met QC Criteria: May 11, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: ABBV-951; Levodopa/Carbidopa (LD/CD); Levodopa Phosphate/Carbidopa Phosphate (LDP/CDP); Parkinson's Disease (PD)
• Additional Relevant MeSH Terms: Synucleinopathies; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurodegenerative Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Parkinson Disease
• Other Study ID Numbers: M15-737; 2019-004235-23 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: AbbVie is committed to responsible clinical trial data sharing. This includes access to anonymized, individual and trial-level data (analysis data sets), as well as other information.
• IPD Sharing Time Frame: For details on when studies are available for sharing visit https://vivli.org/ourmember/abbvie/
• IPD Sharing Access Criteria: To learn more about the process, or to submit a request, visit the following link https://www.abbvieclinicaltrials.com/hcp/data-sharing/
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes