AskBio Inc., a wholly owned subsidiary of Bayer AG, has secured Investigational New Drug (IND) clearance from the United States Food and Drug Administration for AB-1009, an investigational gene therapy for the treatment of late-onset Pompe disease. The regulatory greenlight enables AskBio to begin Phase 1/2 clinical trials in the United States, with patient enrollment expected to begin in early 2026. The therapy uses an adeno-associated virus (AAV) vector developed in partnership with Belief BioMed, which provided capsid licensing and manufacturing support.

What this milestone means for late-onset Pompe treatment and gene therapy progress

The IND clearance for AB-1009 introduces a new front in the effort to treat late-onset Pompe disease using AAV-mediated gene therapy. While enzyme replacement therapy (ERT) has been the standard of care, its limitations—especially in skeletal muscle targeting and long-term durability—have left a significant therapeutic gap. AB-1009 aims to address that gap by delivering a functional copy of the GAA gene directly into muscle cells, potentially offering sustained therapeutic expression and reduced treatment burden.

This marks one of the first programs to target late-onset Pompe with a systemic AAV approach designed to overcome muscle-specific delivery challenges. Gene therapies such as Spark Therapeutics’ SPK-3006 and Audentes’ AT845 have explored similar territories, but AskBio’s approach brings new capsid innovations from Belief BioMed into the clinic, which may influence biodistribution and expression kinetics.

What Belief BioMed’s role reveals about China–U.S. gene therapy integration

The advancement of AB-1009 into clinical testing also illustrates the growing technical integration between Chinese and Western gene therapy ecosystems. Belief BioMed, a Shanghai-based gene therapy company, supplied the AAV capsid used in AB-1009 and led the vector manufacturing for the IND-enabling batch. This collaboration signals a cross-border R&D model increasingly common in next-gen biologics, where capsid design, vector engineering, and manufacturing scale are modularized across geographies.

Industry observers suggest that Belief BioMed’s involvement not only validates its technical capacity in AAV production but also positions it as a vector partner for future ex-China programs. With its own hemophilia B gene therapy already approved by the National Medical Products Administration in China, Belief BioMed appears to be using the AskBio alliance to build clinical referenceability in Western regulatory pathways.

What this program changes in Pompe disease drug development dynamics

The therapeutic landscape in Pompe disease has been historically dominated by enzyme replacement therapies such as alglucosidase alfa (Myozyme) and avalglucosidase alfa (Nexviazyme), both developed by Sanofi. These therapies require chronic infusions and often fail to halt disease progression, especially in late-onset phenotypes.

Gene therapy efforts in Pompe have seen limited clinical translation, partly due to concerns around immunogenicity, vector redosing limitations, and insufficient targeting of skeletal muscle. AB-1009, if successful, may introduce a one-time treatment paradigm that could redefine expectations around disease management, especially for adult patients who are less responsive to traditional ERT.

Clinicians tracking the field will be watching whether AB-1009 can demonstrate both adequate expression levels and long-term durability across skeletal and respiratory muscles. This will require more than just safety—it will depend on biomarker response, strength improvement, and respiratory function preservation across age cohorts.

What could go wrong: unanswered questions around immunogenicity and clinical design

Despite the optimism around AB-1009, the program will need to address long-standing concerns around AAV immunogenicity, especially in late-onset populations who may harbor pre-existing antibodies. Moreover, the durability of transgene expression and the immune response to the GAA protein itself could influence long-term efficacy and safety outcomes.

Another key consideration is the trial’s inclusion and exclusion criteria—how early in the disease course patients are enrolled will significantly affect efficacy readouts. Skeletal muscle degradation may already be advanced by the time of enrollment in adult cases, limiting the perceived benefit in clinical endpoints.

Regulatory watchers note that while FDA’s acceptance of the IND is a positive signal, it does not imply downstream approval ease. The agency may require extended follow-up data and comparator analysis against ERT or other standards of care to support a future Biologics License Application.

Strategic implications for AskBio and Bayer’s broader cell and gene therapy pipeline

For AskBio and its parent Bayer AG, AB-1009 represents more than a single-asset bet—it is a validation play for their AAV platform and a marker of maturity in their neuromuscular pipeline. Bayer has invested heavily in gene therapy infrastructure, including a cell and gene therapy manufacturing facility in Berkeley, and this IND clearance adds clinical weight to that portfolio.

Bayer’s pipeline has historically leaned toward cardiovascular and oncology assets, but with the integration of AskBio and BlueRock Therapeutics, its ambitions in cell and gene therapy are clearly expanding. AB-1009 offers a bridge between rare disease biology and scalable vector design, and if successful, may set the tone for similar approaches in other lysosomal storage disorders.

Strategically, the success of AB-1009 may also enhance AskBio’s visibility in the context of Bayer’s broader innovation funnel and capital allocation decisions. A proof-of-concept success in late-onset Pompe could act as a catalyst for additional licensing partnerships, technology synergies, or even asset prioritization shifts.

What industry will watch next as trials begin

With first patient recruitment expected in early 2026, the field will closely track how quickly the trial accrues patients and what initial safety signals emerge. Skepticism remains around the scalability of systemic AAV gene therapies in adults, especially considering dosing limitations, immune suppression needs, and manufacturing constraints.

Manufacturing readiness will be another critical benchmark. AskBio will need to demonstrate GMP-grade vector supply consistency across the clinical trial’s progression, especially if dose-ranging studies are incorporated.

For Belief BioMed, the trial marks an opportunity to position its capsid platform as validated and clinically active in the U.S. regulatory environment—a move that may open doors to co-development deals or CDMO contracts from Western biotech firms seeking AAV expertise beyond crowded U.S. players.

As gene therapy for rare metabolic and neuromuscular conditions continues to evolve, AB-1009 will serve as a closely watched test case not only for Pompe disease innovation but also for trans-Pacific biotech collaboration.

  AAV vector, AB-1009, AskBio, Bayer AG, Belief BioMed, FDA IND, gene therapy, late-onset Pompe disease, lysosomal storage disorder