Milestones
- Pick first drug for trialsNowCurrent milestone.
- First human trialNot yet reached.
Most important updates
- Dec 2025
- Aug 2025
- May 2025
- 1 Aug 2022
- 19 Jan 2022
Current obstacles
- Safety windowThe dose that rejuvenates is close to the dose that erases a cell's identity, and it differs by tissue.
- Aging isn't a disease (to regulators)Regulators don't treat aging as a disease, so programs must target specific illnesses first.
Physics limits
- Youth and identity are erased by the same switchThe factors that wipe age marks also wipe the marks that make a liver cell a liver cell. Mice kept on the full four factors grow tumours (teratomas) within weeks, so dosing must stay in a narrow window.
- No carrier reaches every cell evenlyViruses and fat bubbles reach some organs, like the liver and eye, far better than others. Cells that get too much risk reverting fully and cells that get too little gain nothing.
- Not all aging is written in the marksReprogramming resets the chemical tags that control genes, but not DNA mutations, stiffened collagen or cells already lost. That damage keeps adding up and caps what a reset can recover.
How it works
Induce
Short burst of factors
Switch on reprogramming factors in old cells, or mimic them with other molecules, for a limited time rather than until cells fully revert.
Reset
Wipe the age marks
The pulse partly erases the chemical tags on DNA that build up with age, so genes act young again.
Retain
Keep cell identity
Stopping before cells lose their special job is the key safety rule.
Update log
Dec 2025
- Minor: PressResearch
Aug 2025
- Minor: PressPeople
May 2025
- Minor: PressCommercial
Mon 1 Aug 2022
- Minor: PressPeople
Thu 14 Jul 2022
- Minor: PressPeople
Thu 2 Jun 2022
- Minor: PressPartnership
Wed 19 Jan 2022
- Major: PressFunding
About Altos Labs
Altos Labs
Making old cells young again
Launched in Jan 2022 with $3B, the biggest start ever for an aging company. Altos runs research labs in the Bay Area, San Diego and Cambridge, UK, where top reprogramming scientists study how to make cells young and healthy again to reverse disease.
- Debuted in Jan 2022 with $3B, the largest launch funding in biotech, with former GSK research head Hal Barron as CEO.
- Its scientists include Juan Carlos Izpisua Belmonte, Wolf Reik, Manuel Serrano and Steve Horvath; Shinya Yamanaka advises.
- Hired aging-trial veteran Joan Mannick as chief medical officer, a sign of moving to trials; none announced yet.
- Founded
- 20215 yrs
- Headquarters
- United StatesUnited Kingdom
- Status
- Private
- Valuation
- private
- Raised
- $3B1 round
- Last round
- Launch financing · $3BJan 2022
- Works in
- LongevityCellular reprogramming
- Coverage
- 1 program · 7 updateslatest 1 Dec 2025checked 25 Sep
- People
- Hal Barron (opens altoslabs.com)CEORick Klausner (opens altoslabs.com)Founder and Chief ScientistJoan Mannick (opens altoslabs.com)Chief Medical Officer