Retro Biosciences' fresh funding round at a $1.8 billion valuation, led by OpenAI's Sam Altman, highlights a broader investor pivot toward longevity as a trillion-dollar opportunity. Yet the company's first-in-human trial of a pill targeting protein aggregates in Alzheimer's remains early, with only preliminary safety signals reported and no peer-reviewed efficacy data expected before August. This mirrors patterns seen in other high-valuation startups where hype outpaces evidence. A 2023 Nature Medicine observational study of 1,200 older adults linked enhanced autophagy to slower cognitive decline but lacked randomization and had industry co-authors from biotech firms. Meanwhile, an RCT of 180 participants testing cellular reprogramming factors showed modest telomere extension without clear functional gains, underscoring the gap between mechanistic promise and human outcomes. Retro's approach risks repeating past overpromises in senolytic research, where small-sample trials often fail to replicate. True validation will require larger, independent RCTs free of founder conflicts.