Development of a secretable frataxin for enhanced efficacy in treating Friedreich’s Ataxia

Daniel M. DuBreuil, Michael Fleming, Yashvi Parikh, Mikaela Woo, Jie Bu, Swathi Ayloo, Ingeborg M. Langohr, Dinesh S. Bangari, Christian Mueller, Shyam Ramachandran, Development of a secretable frataxin for enhanced efficacy in treating Friedreich’s Ataxia, Molecular Therapy Advances, 2025, 201661, ISSN 3117-387X, doi:10.1016/j.omta.2025.201661. 

No disease-modifying therapies are approved for FA, and current gene therapy approaches fail to address the full disease, forcing patients to choose between cardiac protection or neurological benefit. Here, we present ‘Engineered Cross-Correction,’ in which the therapeutic protein is bioengineered for secretion, expanding the therapeutic footprint. We apply this approach to FA by engineering a secretable frataxin and delivering it via a single intra-cerebrospinal fluid (CSF) injection of an adeno-associated viral (AAV) vector equipped with a novel capsid and tissue-selective promoter. We achieved broad protein repletion across key target tissues—heart, dorsal root ganglia, and cerebellum—in mouse and non-human primate. In FA mouse models, we observed rescue of cardiac and neurological phenotypes, marking the first demonstration of dual correction with a single, minimally invasive administration. These benefits were achieved without widespread transduction, reducing vector burden and associated toxicity. Our findings establish a scalable platform that contrasts with intravenous BBB-penetrant gene delivery and offers a generalizable strategy for multi-system disorders. Beyond FA, this positions Engineered Cross-Correction as a new frontier for the next generation of gene therapies.

Using a discrete choice experiments to explore societal preferences for valuing new drugs for rare diseases

Vargas, C., Goodall, S., Street, D.J. et al. Using a discrete choice experiments to explore societal preferences for valuing new drugs for rare diseases. Orphanet J Rare Dis 20, 631 (2025). doi:10.1186/s13023-025-04141-0 

Results In general, respondents had a greater preference for drugs that increase survival, where there was greater confidence in the effectiveness of the new drug and which increased patients’ capacity to do their usual activities. Preferences were not homogenous, the latent class analysis identified three groups: Class 3 (58%) demonstrated a strong preference for improvements in survival; Class 2 (21%) showed a strong preference for confidence in the evidence; and Class 1 (21%) positively valued increased government expenditure. 

Conclusion These results are consistent with previous studies that used different methodologies in showing a preference for drugs with improved survival and quality of life. However, addressing a societal preference for greater confidence in the evidence - reducing evidential uncertainty - represents a methodological and policy challenge for the evaluation of drugs in rare diseases.