Post-Intervention Myocardial Remodeling and Frataxin Expression Following Intravenous Vector Infusion

Article Impact Level: HIGH
Data Quality: STRONG
Summary of  JAMA Cardiology. https://doi.org/10.1001/jamacardio.2026.1699 
Dr. Ronald G. Crystal et al.

Points

Genetic medicine researchers completed a Phase 1 clinical trial evaluating the safety and preliminary efficacy of an intravenous AAVrh.10hFXN gene therapy for Friedreich ataxia cardiomyopathy.
Investigators pooled longitudinal data from 17 adult patients across three escalating dose cohorts who were evaluated over a post-infusion window of 6 to 36 months.
Endomyocardial tissue biopsies obtained three months after the one-hour infusion confirmed that frataxin protein levels successfully increased in all evaluated patient heart samples.
Post-treatment cardiac MRI monitoring revealed a therapeutic decrease in left ventricular mass index alongside a reduction in circulating troponin I markers of myocardial damage.
The cardiotropic viral vector treatment was generally well tolerated by participants with only four serious adverse events recorded, all of which were completely resolved.

Summary

Initiated to address the underlying genetic etiology of a progressive and fatal inherited cardiac disease, this Phase 1 clinical trial evaluated the safety and preliminary efficacy of a novel gene therapy, AAVrh.10hFXN. Friedreich ataxia (FA) is an autosomal recessive disorder caused by pathogenic variants in the frataxin (FXN) gene, which lead to a severe depletion of the FXN protein necessary for mitochondrial cellular energy production. Because the heart is a highly energy-consuming organ, approximately 65% of FA patients succumb to hypertrophic cardiomyopathy and subsequent heart failure. The research sought to determine if systemic intravenous administration of a cardiotropic adeno-associated virus (AAV) vector containing the normal human FXN coding sequence could safely restore tissue frataxin levels and reverse structural myocardial damage.

Pooling data from two independent open-label cohorts from Weill Cornell Medicine and Lexeo Therapeutics, investigators evaluated a combined sample of 17 adults diagnosed with FA cardiomyopathy. Over a longitudinal monitoring window ranging from 6 to 36 months, participants received a single one-hour intravenous infusion of AAVrh.10hFXN across three escalating dose tiers. Safety assessments documented four serious adverse events, all of which successfully resolved, with three possibly related to the accompanying prednisone immunosuppression protocol. Preliminary efficacy was rigorously quantified in eight patients via post-therapy endomyocardial biopsies performed at three months, which demonstrated a uniform increase in tissue frataxin protein expression across all biopted subjects.

Concurrently, functional and structural evaluations indicated favorable myocardial remodeling and a reduction in active cellular injury. Longitudinal cardiac MRI scans revealed a post-infusion decrease in the left ventricular mass index, signaling a reduction in pathologically thickened heart walls. Circulating levels of troponin I, a highly sensitive structural marker of ongoing myocardial damage that is characteristically elevated in this patient population, also decreased following therapeutic intervention. While larger, placebo-controlled clinical trials are required to define explicit relative risk hazard ratios and evaluate long-term neurological stabilization on the modified Friedreich Ataxia Rating Scale (mFARS), these preliminary findings suggest that cardiotropic AAV gene replacement represents a viable therapeutic strategy to modify the natural history of FA cardiomyopathy.

Link to the article: https://jamanetwork.com/journals/jamacardiology/article-abstract/2850507#google_vignette

References

Crystal, R. G., Weinsaft, J. W., Kaminsky, S. M., Caragiulo, A., Savage, N., Patel, A., Gavrilova, R. H., Perlman, S. L., Galbraith, M., Kahlon, U., Krishnan, U., Kaner, R. J., Sanders, A., Vo, M., Sarva, H., Yoo, A., Sondhi, D., De, B. P., Mezey, J. G., … Zesiewicz, T. (2026). Aavrh. 10hfxn gene therapy for the cardiomyopathy of friedreich ataxia: A nonrandomized clinical trial. JAMA Cardiology. https://doi.org/10.1001/jamacardio.2026.1699