Retro Biosciences drugs aging itself — Sam Altman's $180M seed reaches first human trial

Retro Biosciences is Sam Altman's bet that aging itself — not any single age-related disease — is the treatable condition. Founded in 2022 by Joe Betts-LaCroix in San Francisco, it raised a $180M seed round funded entirely by Altman, then in January 2025 began raising a $1B Series A. Its pitch was deliberately unglamorous: take the best-proven aging biology — lysosomal cleanup, cellular reprogramming, microglia — and run it through the same randomized-trial machinery pharma uses for any disease.

By the end of 2025 the bet had its first verifiable milestone: Retro dosed the first participant in a Phase 1 trial of RTR242, an autophagy-restoring small molecule, in a randomized, double-blind, placebo-controlled study in healthy volunteers in Adelaide, Australia. The same period saw its OpenAI collaboration, in which a protein-engineering model redesigned the reprogramming factors Retro uses to rewind cells toward youth, and it kept three programs — autophagy, reprogramming, and microglia cell therapy — in development.

What has not happened yet is efficacy. The Phase 1 study is a safety-and-biomarker trial; no one has shown these drugs add years of healthy life in humans. Retro's declared first target is Alzheimer's, betting that cellular-clearance failure is upstream of neurodegeneration. Reported valuations have run ahead of the data — which is exactly why the company works so hard to have data at all.