Matt Kaeberlein recently noted that he tried, but could not get funding for, a rapamycin mouse study starting the mice later in life (most studies so far target early adulthood - e.g. 9 months for a mouse, equivalent to 20 to 30 in a human), or 20 months (40 to 60 in a human).
Matt wanted to start at 28 months of age for the mice), perhaps equivalent to the late 70s, or early 80s in human terms.
These comments were in the thread of commentary about the recent partial cellular reprogramming results that were posted by David Sinclaire, for mouse life extension: