Lexeo Reports Promising Interim Phase 1/2 Results for LX2006 in FA Cardiomyopathy, Plans Registrational Study

NEW YORK, April 07, 2025 (GLOBE NEWSWIRE)  – Lexeo Therapeutics, Inc. (Nasdaq: LXEO), a clinical-stage genetic medicine company focused on innovative treatments for cardiovascular diseases, today announced compelling positive interim data across all dose cohorts of LX2006, its AAV-based gene therapy, for Friedreich ataxia (FA) cardiomyopathy. Data from both the Lexeo-sponsored SUNRISE-FA Phase 1/2 trial (NCT05445323) and the Weill Cornell Medicine investigator-initiated Phase 1A trial (NCT05302271) demonstrated that treatment with LX2006 resulted in clinically significant improvements in cardiac biomarkers and functional measures, alongside increased frataxin protein expression in all participants who underwent cardiac biopsies.

“These data provide strong evidence that LX2006 is acting as a beneficial disease-modifying treatment candidate, supporting its continued development as a potential first- and best-in-class therapy for FA cardiomyopathy,” said Dr. Eric Adler, Chief Medical Officer and Head of Research at Lexeo Therapeutics. “The clinical and functional improvements we’ve observed across these studies could be transformational to the standard of care, especially given that cardiac dysfunction is the leading cause of death for people with FA.”

LX2006 is an AAV-based gene therapy designed to address the cardiac manifestations of Friedreich ataxia by delivering a functional frataxin gene to promote the expression of the frataxin protein in myocardial cells, aiming to restore mitochondrial function.

The interim analysis (data cutoff March 25, 2025, n=12 with >6 months follow-up) showed significant improvements in left ventricular mass index (LVMI), with 5 of 6 participants with abnormal baseline LVMI achieving >10% improvement and the majority reaching normal range. Dose-dependent improvements were observed, with mid- and high-dose cohorts showing greater and earlier benefits. Additionally, significant reductions were seen in lateral wall thickness and high-sensitivity troponin I. Notably, cardiac biopsies (n=8) showed increased frataxin protein expression in all participants at 3 months, with a mean increase of 115% in the high-dose cohort.

Dr. Sandi See Tai, Chief Development Officer at Lexeo, stated that these data exceed thresholds aligned with the FDA to support accelerated approval. The company expects to initiate a registrational study by early 2026, following alignment with the FDA on co-primary endpoints of LVMI (>10% improvement at 12 months) and frataxin expression (any increase from baseline at three months). Lexeo plans to begin enrollment in a prospective natural history study in Q2 2025 to serve as an external control arm. Treatment with LX2006 has been generally well tolerated with no Grade 3+ serious adverse events to date. LX2006 has received multiple regulatory designations from the FDA and the European Commission for the treatment of FA cardiomyopathy.