Lexeo May Gain Faster FDA Approval for Friedreich’s Ataxia Gene Therapy

NEW YORK, NY –October 7, 2025– Lexeo Therapeutics said today it could apply for an even earlier accelerated approval of its AAV gene therapy, LX2006, which treats heart muscle disease (cardiomyopathy) in people with Friedreich’s ataxia (FA). The company’s shares ($LXEO) surged 30% at market open following the news.

The U.S. Food and Drug Administration (FDA) is open to the idea of pooling clinical data from Lexeo’s current Phase 1/2 gene therapy trial with results from its planned pivotal trial. According to Lexeo CEO R. Nolan Townsend, this agreement could enable the company to run a smaller pivotal study.

Strong Clinical Data and AAV Delivery

LX2006 is being studied to treat Friedreich’s ataxia cardiomyopathy, the leading cause of death in people with the rare, degenerative condition. The disease is caused by a deficiency in the protein frataxin. The gene therapy uses viral envelopes called AAVs to deliver a functional frataxin gene to heart cells.

Updated Phase 1/2 Results:

Lexeo also reported updated results from its Phase 1/2 trial, showing strong efficacy signals:

• Five of six patients saw greater than 10% improvement on the primary endpoint, left ventricular mass index (LVMI), by one year.
• All six patients reached LVMI measures within the normal range as of their latest visit.

Higher LVMI indicates an abnormal thickening of the heart wall, making it harder for the heart to pump blood. The FDA previously agreed that the LVMI endpoint could be evaluated earlier than one year in the pivotal trial.

Regulatory Path:

• The company plans to start its pivotal trial in the first half of next year.
• To utilize pooled data, Lexeo must submit manufacturing comparability analysis and nonclinical results, as its future gene therapy manufacturing process will differ from the Phase 1/2 study.

Safety data from 17 participants across both the Lexeo-sponsored Phase 1/2 SUNRISE-FA trial and an investigator-sponsored Phase 1a study showed that the gene therapy “has been generally well tolerated” with “minimal, transient” elevations on liver enzyme tests.