Although much less of a public figure than his new boss, O’Neill is quite well-known in the increasingly well-funded and tight-knit longevity community. His acquaintances include the prominent longevity influencer Bryan Johnson, who describes him as “a soft-spoken, thoughtful, methodical guy,” and the billionaire tech entrepreneur Peter Thiel. In speaking with more than 20 people who work in the longevity field and are familiar with O’Neill, it’s clear that they share a genuine optimism about his leadership. “There’s nothing worse than getting a bunch of [early-stage unproven therapies] on the market,” she says. Those products might be dangerous and could make people sick while enriching those who develop or sell them.