The Fortune Visionaries

In 2004, the serial entrepreneur created Sirtris Pharmaceuticals with Harvard Medical School researcher David Sinclair. Sinclair spearheaded research on resveratrol, which targets proteins that play a key role in the aging process.

Sirtris is in phase 2 clinical trials for potent drugs called New Chemical Entities, which replicate the effects of resveratrol. High-profile investors like famed investor Peter Lynch and Red Sox owner John Henry backed Sirtris before it was scooped up by GlaxoSmithKline (GSK) in 2008, for $720 million.

Mice given the company's drug exhibit Olympic athlete level stamina, but Westphal notes the drugs are intended to treat diseases associated with aging, like diabetes and Alzheimer's, not aging itself.

Says Westphal: "If instead of treating the symptoms when the disease has already occurred, we could successfully attack the root cause with one of our drugs, I think it could ultimately have a very profound effect on increasing health span or lifespan."

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