Gene therapy companies Lexeo Therapeutics and Tenaya Therapeutics are pioneering treatments targeting cardiovascular diseases caused by single-gene mutations. Utilizing adeno-associated viruses (AAV) as delivery vectors, these therapies aim to correct defective genes in heart muscle cells through a single intravenous infusion, offering sustained therapeutic protein production. Both companies have candidates currently in Phase I/II trials, reflecting a growing trend towards applying gene therapy beyond rare genetic disorders into common cardiovascular conditions.