RJB-01

**RJB-01** is an adeno-associated virus gene-therapy combination developed by Rejuvenate Bio for canine myxomatous mitral valve disease and associated heart failure. It delivers genetic payloads encoding fibroblast growth factor 21 and soluble transforming growth factor beta receptor 2, aiming to increase FGF21 activity and suppress profibrotic transforming growth factor beta 1 signaling. In a pilot study in Cavalier King Charles Spaniels with myxomatous mitral valve disease, the program showed durable transgene expression, bioactivity, and a favorable reported safety profile; it remains investigational and has not been approved. ([businesswire.com](https://www.businesswire.com/news/home/20230518005611/en/Rejuvenate-Bio-Announces-Data-for-Gene-Therapy-RJB-01-in-Mitral-Valve-Disease-at-2023-Meeting-of-the-American-Society-of-Gene-and-Cell-Therapy-ASGCT))