A Study of AB-1005 Gene Therapy in Japanese Adults With Moderate Parkinson's Disease (J-REGENERATE-PD) (J-REGENERATE-P)

A Phase 2, Open-label, Single Group, Fixed-dose Study to Evaluate the Safety and Efficacy of a Single Bilateral Intraputaminal Administration of AB-1005 (AAV2-GDNF Gene Therapy) in Japanese Participants With Moderate Stage Parkinson's Disease

The objective of this Phase 2, open-label, single group, one-time, fixed-dose study is to assess the safety and efficacy of bilateral intraputaminal infusion of AB-1005 (AAV2-GDNF gene therapy) in Japanese patients with moderate Parkinson's Disease (PD).

Study Overview

• Status: Not yet recruiting
• Conditions: Parkinson Disease
• Intervention / Treatment: Drug: AB-1005

• Study Type: Interventional
• Enrollment (Estimated): 8
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Bayer Clinical Trials Contact; Phone Number: 18888422937; Email: clinical-trials-contact@bayer.com

Study Locations

• Japan
  • Kyoto, Japan, 616-8255
    • National Hospital Organization Utano National Hospital - Neurology
  • Osaka, Japan, 560-8552
    • National Hospital Organization Osaka Toneyama Medical Center - Neurology
  • Aichi-ken
    • Nagoya, Aichi-ken, Japan, 453-0801
      • Nagoya Central Hospital - Neurosurgery
    • Nagoya, Aichi-ken, Japan, 466-8560
      • Nagoya University Hospital - Neurology
  • Kanagawa
    • Yokohama, Kanagawa, Japan, 232-0024
      • Yokohama City University Medical Center - Neurology
  • Tokyo
    • Bunkyo-ku, Tokyo, Japan, 113-8431
      • Juntendo University Hospital - Neurology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male and female adults 45-75 years of age inclusive, at the time of signing of informed consent

• Diagnosed with Parkinson's disease in the past 4-10 years (inclusive) and currently meeting all the following criteria:

  1. Presence of bradykinesia PLUS any of the following: rigidity, rest tremor, postural instability
  2. Presence of motor fluctuations as measured by the PD Motor Diary
  3. Stable anti-parkinsonian medication regimen for 4 weeks or more, prior to screening
  4. Responsiveness to levodopa therapy

Exclusion Criteria:

• Known history or current evidence of medical, genetic, or neurological conditions that may provide an alternative to idiopathic PD diagnosis
• Presence or history of significant vascular and/or cardiovascular disease
• Presence of clinically significant cognitive impairment
• Presence or history of psychosis or impulse control disorder
• History of malignancy other than treated cutaneous squamous or basal cell carcinomas
• Presence of clinically relevant conditions that could compromise surgical suitability and/or subject safety
• Contraindication to magnetic resonance imaging and/or use gadolinium-based contrast agents
• Prior history of brain surgery including, but no limited: DBS, pallidotomy focused ultrasound thalamotomy, or other experimental neurosurgical procedure
• Chronic immunosuppressive therapy

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: AB-1005 infusion	Drug: AB-1005; Bilateral image-guided infusion of AAV2-GDNF into putamen, single dose

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of adverse events up to Month 18 after study intervention	Number and proportion of participants with at least one adverse event	Up to 18 months
Change from Baseline to Month 18 in normalized Good ON time measured with PD Motor Diary		Up to 18 months

Collaborators and Investigators

• Sponsor: Bayer
• Collaborators: AskBio Inc

Study record dates

Study Major Dates

• Study Start (Estimated): July 27, 2026
• Primary Completion (Estimated): December 15, 2028
• Study Completion (Estimated): June 15, 2032

Study Registration Dates

• First Submitted: April 28, 2026
• First Submitted That Met QC Criteria: April 28, 2026
• First Posted (Actual): May 5, 2026

Study Record Updates

• Last Update Posted (Actual): June 5, 2026
• Last Update Submitted That Met QC Criteria: June 4, 2026
• Last Verified: May 21, 2026

More Information

Terms related to this study

• Keywords: Gene therapy
• 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: 23015; ASK-PD5-CS203 (Other Identifier: Study ID)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

IPD Plan Description

Currently, there is no established plan for the sharing of Individual Patient Data (IPD) from this study. The availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA 'Principles for responsible clinical trial data sharing.' This pertains to the scope, timepoint, and process of data access.

As such, Bayer commits to considering requests from qualified researchers for patient- / study-level clinical trial data, and documents from clinical trials involving medicines and indications approved in the US and EU. However, this commitment does not reflect an active IPD sharing plan. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014.

Researchers can use www.vivli.org to request access to IPD and documents from clinical studies to conduct research. Information on Bayer's criteria for listing studies is provided in the member section of the portal.

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