Simply put, we believe the gene therapy demonstrated in both animal species, especially in the cow, very well showcases the therapeutic potential for MSUD, in part because the diseased cow, without treatment, has a very similar metabolic profile as the patients, said Dan Wang, PhD, assistant professor of genetic & cellular medicine

Dr. Wang is co-principal investigator with Heather Gray-Edwards, DVM, PhD, assistant professor of genetic & cellular medicine; Guangping Gao, PhD, the Penelope Booth Rockwell Chair in Biomedical Research, director of the Horae Gene Therapy Center, director of the Li Weibo Institute for Rare Diseases Research and chair and professor of genetic & cellular medicine.

The study, published in Science Translational Medicine, was partially funded through an agreement with ASC Therapeutics, a privately held biopharmaceutical company developing in-vivo gene replacement, gene editing and allogeneic cell therapies

MSUD is a rare genetic inborn error of metabolism characterized by recurrent life-threatening neurologic crises and progressive brain injury that can only be managed with an exacting prescription diet or liver transplant from a donor.  

Researchers in the current study designed a dual-function recombinant adeno-associated virus serotype 9 vector to deliver a gene replacement to the liver, muscle, heart and brain. 

We believed gene therapy could be a breakthrough for patients with MSUD and, in August 2018, met on a cattle farm in Iowa to pursue that vision: to develop and test gene therapy in a unique animal model, a newborn calf with MSUD. In the years that followed, physicians at the Clinic for Special Children worked intently with scientists and veterinarians from UMass Chan Medical School to achieve that goal, drawing their inspiration from the hopes and struggles of the MSUD community. For people worldwide living with MSUD, this signifies major progress on the path to a brighter future.

Source: https://www.umassmed.edu/news/news-archives/2025/02/gene-therapy-developed-for-maple-syrup-urine-disease-shows-promise-new-umass-chan-study-reports/