Hope on the Horizon: IntraBio Submits First-Ever Drug for Ataxia-Telangiectasia Approval

AUSTIN, TX – March 20, 2026 – In a move that could mark a pivotal moment for thousands of families worldwide, IntraBio Inc. has officially submitted an application to the U.S. Food and Drug Administration (FDA) for the first-ever approved treatment for Ataxia-Telangiectasia (A-T), a rare and devastating neurodegenerative disorder. The Austin-based biopharmaceutical company is seeking to expand the use of its drug, levacetylleucine, to treat the progressive condition that currently has no disease-modifying therapies.

The drug, marketed as AQNEURSA®, is already approved in the United States for treating neurological manifestations of another rare condition, Niemann-Pick disease type C (NPC). This supplemental New Drug Application (sNDA) represents a beacon of hope for the A-T community, which has long navigated the relentless progression of the disease without a single approved pharmaceutical intervention.

A Breakthrough for a Devastating Disease

For patients and families affected by Ataxia-Telangiectasia, the news represents a potential turning point. A-T is an inherited, autosomal recessive disorder that typically manifests in early childhood, just as toddlers are learning to walk. The disease is characterized by the progressive degeneration of the cerebellum, the brain's center for coordination and balance. This leads to a cascade of debilitating symptoms, including worsening ataxia (loss of coordination), impaired speech, and abnormal eye movements.

Most children with A-T become dependent on a wheelchair by the age of 10. The disease's reach extends beyond motor function, often causing immune deficiencies that lead to life-threatening infections, chronic lung disease, and a dramatically increased risk of cancer. Life expectancy is significantly shortened, with many patients succumbing to the disease in early adulthood. To date, the standard of care has been entirely supportive, focusing on managing symptoms through physical therapy and treating secondary complications, rather than slowing the disease itself.

The profound unmet need makes the results from IntraBio's clinical trial particularly significant. Dr. Franziska Hoche, a principal investigator in the study and an assistant professor of neurology at Mass General Research Institute, called the findings a "breakthrough for patients and families affected by Ataxia-Telangiectasia." In a statement, she highlighted the historic nature of the results, noting they provide "compelling evidence of levacetylleucine’s meaningful impact on the lives of patients with A-T."

This sentiment is echoed by patient advocacy groups like the A-T Children's Project, which has worked for decades to fund research and accelerate the development of therapies. Brad Margus, the organization's founder, stated that the drug offers "real hope that families will soon have access to their first effective and safe treatment approved for A-T."

The Science Behind the Submission

The company's confidence is built on a foundation of robust clinical data from its pivotal Phase III trial, known as IB1001-303. The study, which enrolled both pediatric and adult patients with A-T, was designed as a randomized, double-blind, placebo-controlled crossover trial—a gold standard in clinical research. This design allows each participant to serve as their own control, providing a powerful comparison of the drug's effect versus a placebo.

The trial met its primary goal with high statistical significance. After 12 weeks of treatment, patients taking levacetylleucine showed a clinically meaningful improvement of -1.92 points on the Scale for the Assessment and Rating of Ataxia (SARA), a standard measure of disease severity. In stark contrast, patients on placebo saw a negligible change of -0.14 points. The difference between the two groups was highly statistically significant (p<0.001).

Key secondary endpoints reinforced these positive findings. Patients on levacetylleucine also demonstrated significant improvements on the International Cooperative Ataxia Rating Scale (ICARS) and the Investigator's Clinical Global Impression of Improvement (CGI-I) scale. According to IntraBio, the clinical benefit was consistent across all patient subgroups, regardless of age, gender, or disease severity at the start of the trial.

Crucially, levacetylleucine was reported to be generally safe and well-tolerated, with no drug-related serious adverse events observed. This safety profile is consistent with its existing track record in patients with Niemann-Pick disease type C, which likely provides regulators with an additional layer of confidence.

Navigating the Regulatory Gauntlet

Submitting the first-ever application for a disease is a major regulatory milestone. To encourage the development of drugs for rare conditions like A-T, the FDA has established several programs to expedite the review and approval process. IntraBio's levacetylleucine is well-positioned to benefit from these pathways.

The drug has already been granted both Orphan Drug Designation (ODD) and Rare Pediatric Disease Designation (RPDD) by the FDA. ODD provides incentives like tax credits, waived user fees, and a potential seven years of market exclusivity upon approval. The RPDD, which acknowledges the serious unmet need in children, makes IntraBio eligible to receive a Priority Review Voucher if the drug is approved. These vouchers can be used to shorten the FDA review of a future drug from 10 months to 6 months and can be sold to other pharmaceutical companies, often for tens of millions of dollars.

Given the positive Phase III data and the lack of any existing treatments, IntraBio is likely to seek Priority Review for the application itself. If granted, this would set an accelerated review timeline of six months, potentially leading to an approval decision before the end of the year.

A Strategic Move in a Competitive Field

For IntraBio, this submission is a key part of a broader corporate strategy focused on leveraging its platform to address multiple rare neurological disorders. By seeking to expand the label of an already-approved drug, the company is following an efficient and well-trodden path to maximize the value of its asset while addressing significant unmet medical needs. The company, which recently relocated its headquarters to Austin, has secured over $40 million in new funding to support its commercialization efforts.

While IntraBio may be first to the regulatory finish line, it is not alone in the race to treat A-T. Quince Therapeutics is also advancing its candidate, EryDex, through a Phase III trial. The company recently announced it had enrolled over 75% of its target participants and aims to submit its own application to the FDA in 2026 if the trial is successful. This emerging competition underscores the growing scientific interest in tackling A-T after decades of limited progress.

With a diagnosed patient population of approximately 4,600 in the U.S., the market for an A-T therapy falls squarely within the rare disease category. The first therapy to gain approval will not only have a first-mover advantage but will also set a new standard of care. For now, the A-T community, researchers, and investors will be watching the FDA closely as it begins its review of an application that carries the weight of decades of hope.