A Study to Evaluate Safety, Tolerability, and Efficacy of AB-1009 Gene Therapy (GAA Gene) in Adult Participants With Late-Onset Pompe Disease (PROGRESS-GT LOPD)

A Single-Arm, Open-Label, Dose-Escalation Study to Evaluate the Safety, Tolerability and Efficacy of a Single Intravenous Infusion of AB-1009 in Adult Participants With Late-Onset Pompe Disease (LOPD)

This is a single-arm, open-label, dose-escalation study to evaluate the safety, tolerability and efficacy of a single intravenous infusion of AB-1009 in adult participants with late-onset Pompe disease (LOPD).

Study Overview

• Status: Recruiting
• Conditions: Pompe Disease (Late-onset); LOPD; Pompe Disease Late-Onset
• Intervention / Treatment: Genetic: AB-1009 (GAA Gene)

Detailed Description

This is an open-label study, up to 12 participants will receive a single IV infusion of AB-1009. Participants will be assigned to either cohort 1 (1.0E13 vg/kg) or Cohort 2 (1.5E13 vg/kg) based on enrollment in the study.

Study duration will include a screening period of up to 75 days, primary observation of 52 weeks, and a long-term follow-up period of 4 years.

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: AskFirst Patient Engagement; Phone Number: 919-561-6210; Email: AskFirst@AskBio.com

Study Locations

• United States
  • Arizona
    • Phoenix, Arizona, United States, 85013
      • Not yet recruiting
      • Barrow Neurological Institute
      • Principal Investigator: Shafeeq Ladha, MD
  • California
    • Irvine, California, United States, 92697
      • Recruiting
      • University of California, Irvine (UCI)
      • Principal Investigator: Tahseen Mozaffar, MD
      • Contact: UCI Alpha Clinic; Phone Number: 949-824-3990; Email: alphaclinic@hs.uci.edu
    • Palo Alto, California, United States, 94304
      • Not yet recruiting
      • Stanford Neuroscience Health Center
      • Principal Investigator: John Day, MD, PhD
  • New York
    • New York, New York, United States, 10016
      • Not yet recruiting
      • NYU Langone
      • Principal Investigator: Nicolas Abreu, MD
  • North Carolina
    • Durham, North Carolina, United States, 27705
      • Recruiting
      • Duke University
      • Principal Investigator: Natalie Katz, MD, PhD
      • Contact: Ming Xu, RN, MSN; Phone Number: 919-681-1945; Email: mingfen.xu@duke.edu
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Recruiting
      • Hospital of the University of Pennsylvania
      • Principal Investigator: Paul McIntosh, MD
      • Contact: Amanda Hicks; Phone Number: 267-496-3772; Email: Amanda.Hicks@pennmedicine.upenn.edu
      • Contact: Abigail Browngoehl; Email: Abigail.Browngoehl@Pennmedicine.upenn.edu
    • Pittsburgh, Pennsylvania, United States, 15213
      • Not yet recruiting
      • University of Pittsburgh Medical Center (Upmc)
      • Principal Investigator: Paula Clemens, MD
  • Texas
    • Dallas, Texas, United States, 75235
      • Recruiting
      • University of Texas Southwest Medical Center
      • Principal Investigator: Markey McNutt, MD, PhD
      • Contact: Juana Luevao; Phone Number: 214-645-7411; Email: geneticsresearch@utsouthwestern.edu
      • Contact: Markey McNutt, MD, PhD; Phone Number: 214-645-7411; Email: geneticsresearch@utsouthwestern.edu
  • Virginia
    • Richmond, Virginia, United States, 23298
      • Not yet recruiting
      • Virginia Commonwealth University (VCU)
      • Principal Investigator: Susan Sparks, MD, PhD

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Participant must be ≥18 to ≤65 years of age at the time of signing the informed consent form.
2. Confirmed GAA enzyme deficiency from any tissue source and/or confirmed biallelic GAA gene mutations.
3. Undergone enzyme replacement treatment (ERT) (either alglucosidase alfa (Lumizyme®), avalglucosidase alfa-ngpt (Nexviazyme®)), or cipaglucosidase alfa (Pombiliti®) for at least 6 months (at least 10 infusions) before signing the initial informed consent form. During the screening process, participants need to remain on their current ERT until close to dosing;
4. FVC in the upright position ≥30% and ≤80% of predicted;
5. Capable of walking at least 100 meters in the 6MWT (use of a cane, quad cane, or standard walker is permitted);
6. Male or female. Contraceptive/barrier use by men and women requirements as per protocol.
7. Capable of giving informed consent.
8. Able to understand and comply with all study procedures.

Exclusion Criteria:

1. Severe cardiomyopathy, defined as left ventricular ejection fraction (LVEF) <40% or New York Heart Association (NYHA) functional class 3 or above;
2. Require invasive mechanical ventilation, or rely on noninvasive ventilation during the day;
3. Intolerance to ERT or investigator-assessed intolerance to ERT, prior experience of serious ERT-related infusion-associated reactions (IARs);
4. Have known intrinsic liver diseases, including hepatitis, HIV-related liver disease, prior diagnosis of portal hypertension, splenomegaly, hepatic encephalopathy, severe fatty liver, cirrhosis or liver fibrosis ≥stage 2, ultrasound-identified liver neoplasms, or laboratory tests suggesting elevated alpha-fetoprotein. Patients with liver function tests including ALT or AST >3× upper limit of normal (ULN) or any total bilirubin above ULN during screening will also be excluded;
5. Prior or ongoing medical condition(s), including any active infection, malignancy within 5 years of screening (except basal or squamous cell skin cancer), physical finding(s), assessment findings, or laboratory abnormality that, in the investigator's opinion, would impact participant's safety and compliance with the study procedures.
6. Have received gene therapy prior to screening;
7. Have received any systemic immunosuppressants (except inhalation or topical use) other than glucocorticoids 30 days prior to screening through completion of screening through completion of screening, and/or known intolerance to immunosuppressants such as glucocorticoids; other concomitant immunosuppression would require sponsor approval.
8. Use of investigational drugs or drugs that could affect this study as evaluated by the investigator within 30 days prior to screening through completion of Week 52 or within 5 half-lives of the investigational drug (whichever is longer);
9. Have received any vaccine within 30 days prior to dosing;
10. Other conditions that make the participant not eligible for the study according to the investigator.
11. Contraindication to MRI, hypersensitivity to contrast dyes, shellfish, or iodine, or implanted spinal rods, cardiac pacemaker, or other implantation that would distort cMRI images.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort 1; 1.0E13 vg/kg	Genetic: AB-1009 (GAA Gene); A single intravenous infusion of AB-1009
Experimental: Cohort 2; 1.5E13 vg/kg	Genetic: AB-1009 (GAA Gene); A single intravenous infusion of AB-1009

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Incidence and severity of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs) during the primary observation period	Day 1 (Dosing) through Week 52 (the end of the primary observation period)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area under the curve (AUC) of GAA activity in serum		Baseline through Week 52
Viral shedding (whole blood, saliva, urine)		Day 1 through Week 24 (or until 3 consecutive data points are at or below the limit of detection)
AUC of urinary Glc4		Baseline during the primary observation period (through Week 52)
Change from baseline in GAA activity in muscle biopsy tissue at Week 52		Baseline and Week 52
Change from baseline in muscle biopsy glycogen content at Week 52		Baseline and Week 52
Change from baseline in forced vital capacity (FVC) (% predicted) at Week 24 and Week 52		Baseline, Week 24, and Week 52
Change from baseline in maximum inspiratory pressure (MIP) at Week 24 and Week 52		Baseline, Week 24, and Week 52
Change from baseline in maximum expiratory pressure (MEP) at Week 24 and Week 52		Baseline, Week 24, and Week 52
Change from baseline in distance walked in the 6-Minute Walk Test (6MWT) at Week 24 and Week 52		Baseline, Week 24, and Week 52
Patient's Global Impression of Change (PGI-C) at Week 24 and Week 52	Score range: 1-7; lower scores indicate greater improvement and a better outcome.	Week 24 and Week 52
Clinical Global Impression of Change (CGI-C) at Week 24 and Week 52	Score range: 1-7; lower scores indicate greater improvement and a better outcome	Week 24 and Week 52
Change from baseline in Patient-Reported Outcomes Measurement Information System (PROMIS) for physical function changes at Week 24 and Week 52	PROMIS Short Form v2.0- Physical Function 20a consists of 20 questions that are scored on a scale of 1 to 5. The total score (i.e. sum) ranges between 20 and 100, with a higher score indicating better physical functioning.	Baseline, Week 24, and Week 52
Change from baseline in Patient-Reported Outcomes Measurement Information System (PROMIS) for fatigue changes at Week 24 and Week 52	PROMIS Short Form v1.0- Fatigue 8a consists of eight questions, scored on a scale of 1 to 5. The total score (i.e. sum) ranges between 8 and 40, with lower scores indicating less fatigue.	Baseline, Week 24, and Week 52

Collaborators and Investigators

• Sponsor: AskBio Inc
• Collaborators: Bayer

Study record dates

Study Major Dates

• Study Start (Actual): April 15, 2026
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): September 1, 2032

Study Registration Dates

• First Submitted: November 26, 2025
• First Submitted That Met QC Criteria: December 5, 2025
• First Posted (Actual): December 15, 2025

Study Record Updates

• Last Update Posted (Actual): July 20, 2026
• Last Update Submitted That Met QC Criteria: July 17, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Gene Therapy; Neuromuscular Disease; Pompe Disease; Acid Maltase Deficiency Disease; LOPD; Lysosomal Storage Diseases; Acid Maltase Deficiency; Glycogen Storage Disease; Adeno-Associated Virus (AAV); AB-1009; GAA gene; Late-Onset Pompe Disease; Acid Alpha-Glucosidase (GAA)
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Metabolic Diseases; Carbohydrate Metabolism, Inborn Errors; Brain Diseases, Metabolic, Inborn; Brain Diseases, Metabolic; Lysosomal Storage Diseases, Nervous System; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Nutritional and Metabolic Diseases; Glycogen Storage Disease Type II; Glycogen Storage Disease; Neuromuscular Diseases; Lysosomal Storage Diseases; Glycoside Hydrolases; Hydrolases; Enzymes; Enzymes and Coenzymes; Glucosidases; alpha-Glucosidases
• Other Study ID Numbers: ASK-POM9-CS101

Plan for Individual participant data (IPD)

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

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No