AskBio’s Late-Onset Pompe Disease Gene Therapy AB-1009 Cleared for Phase 1/2 Trial

AskBio’s investigational new drug (IND) application for AB-1009, a gene therapy candidate intended to treat late-onset Pompe disease (LOPD), has been cleared by the FDA.¹

In light of the IND clearance, AskBio has launched the phase 1/2 AB-1009 PROGRESS-GT LOPD clinical trial (NCT07282847). The company expects that the first patient will be enrolled in “early 2026”.¹

AskBio noted that AB-1009 also recently received fast track and orphan drug designations from the FDA. The company also stated that Belief BioMed Inc., Genethon, and Duke University collaborated on AB-1009's advancement to the clinical stage.

“This investigational gene therapy is being studied for its potential to address the underlying genetic defect and to explore whether it can increase production of the deficient enzyme in patients with Pompe disease,” Tahseen Mozaffar, MD, the director of the UCI Health ALS & Neuromuscular Center and the principal investigator of the AB-1009 clinical trial program, said in a statement.¹ “Patients receiving gene therapy may reduce reliance on exogenous enzyme replacement. AskBio’s approach leverages its experience in gene therapy development as it seeks to advance treatment options for Pompe disease.”

Notably, AB-1009 is not AskBio’s first gene therapy program for LOPD. In 2019, the company dosed the first patient in a phase 1/2 clinical trial (ACT-CS101; NCT03533673) evaluating an adeno-associated virus (AAV) vector-based gene therapy candidate referred to as ACTUS-101.² ACT-CS101 surpassed its primary completion date on September 30, 2022, but is still active with an estimated completion date of March 2026. Alongside the announcement of AB-1009's IND clearance, AskBio stated that ACT-CS101 will remain active through completion, but is not recruiting new patients.1 According to ACT-CS101's clinicaltrials.gov page, 7 patients have been enrolled in that trial.

“These advancements in the AB-1009 program, particularly the recently granted regulatory designations, highlight the recognized need for late-onset Pompe treatments,” Mansuo Shannon, PhD, the chief scientific officer of AskBio, added to the statement.¹ “Today’s news demonstrates AskBio’s commitment to progressing early-stage assets into the clinic and adding those to our clinical portfolio.”

On January 14, 2026, Genethon reported that it and AskBio had signed a global licensing agreement through which AskBio will obtain exclusive access to use a component of AB-1009 developed by Genethon that is patented by the latter company and several other French institutions.³ According to the Genethon press release, a team at Genethon led by Giuseppe Ronzitti, PhD, the director of scientific forecasting at Genethon, developed a gene therapy approach for LOPD that provides a gene for a truncated form of the disease-targeted enzyme acid alpha-glucosidase (GAA). The company noted that the gene therapy approach demonstrated the ability to correct the accumulation of glycogen in the central nervous system and in muscle, and that it improved muscular and respiratory dysfunction and cardiac hypertrophy.

“Genethon is delighted with this agreement with AskBio, which enables the development of a gene therapy for patients suffering from this particularly severe condition,” Frédéric Revah, PhD, the CEO of Genethon, said in a statement.³

AB-1009 is not the only gene therapy AskBio is developing for a neurology indication. At the 4th Annual Advanced Therapeutics in Movement and Related Disorders (ATMRD) Congress, held by the PMD Alliance June 27 to 30, 2025, the company presented data from a phase 1b trial evaluating AB-1005, an investigational AAV vector-based gene therapy for the treatment of Parkinson disease.^4,5 In the phase 1b trial, a 1-time infusion of AB-1005 into the putamen was well tolerated, with no serious adverse events associated with the gene therapy at 36 months. After the congress, Nisha Chhabria, MD, FAAN, medical director of CNS clinical development at AskBio, who presented the data, spoke with NeurologyLive® to provide further details on the outcomes from the study.

REFERENCES
1. AskBio Announces FDA Acceptance of Investigational New Drug (IND) Application for AB-1009 Gene Therapy for Treatment of Late-Onset Pompe Disease (LOPD). News release. AskBio Inc. January 8, 2026. Accessed January 21, 2026.  https://www.askbio.com/fda-acceptance-of-investigational-new-drug-ind-application-for-ab-1009-gene-therapy/
2. First patient dosed with gene therapy in phase 1/2 study of ACTUS-101 in patients with Pompe disease. News release. AskBio Inc. January 22, 2019. Accessed January 21, 2026. https://www.askbio.com/first-patient-dosed-with-gene-therapy-in-phase-1-2-study-of-actus-101-in-patients-with-pompe-disease/
3. Genethon signs licensing agreement with AskBio for the development of an investigational gene therapy for Pompe disease. News release. Genethon. January 14, 2026. Accessed January 21, 2026. https://www.genethon.com/genethon-signs-licensing-agreement-with-askbio-for-the-development-of-an-investigational-gene-therapy-for-pompe-disease/
4. AskBio presents 18-month phase 1b trial results of AB-1005 gene therapy for patients with Parkinson disease. News release. AskBio. April 16, 2024. Accessed August 14, 2025. https://www.globenewswire.com/news-release/2024/04/16/2863581/0/en/AskBio-presents-18-month-Phase-Ib-trial-results-of-AB-1005-gene-therapy-for-patients-with-Parkinson-s-disease.html
5. Phielipp N, Christine C, Merola A, et al. Preliminary efficacy of GDNF gene therapy (AAV2-GDNF; AB-1005) in Parkinson’s disease: 36-month follow-up from a phase 1b study. Presented at: ATMRD 2025; June 27-30, 2025; Washington, DC.