New companies are developing improved viral vectors for gene delivery to overcome challenges in lifespan extension.

“One word about those viruses is that it's still early days on gene delivery. One of the reasons we haven't immediately had success with extending the lifespan of mice, is that those viruses are very hard to distribute evenly through the body. Even in even humans, it's a struggle for diseases that want to be treated holistically. But there are advances, there're a number of new companies that have sprung up that allow these viruses to infect the body more evenly. And when that happens, I think we will be able to make mice that can live a decade or two.”