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Rejuvenate Bio—Rejuvenate Bio raises $6M led by VCapital and signs an animal-health gene therapy R&D collaboration with Merck Animal Health

OSK partial reprogramming gene therapy

by Rejuvenate BioUS

ResearchStage 1 of 5

Lab stage; longer life reported in old mice.

Updated Jan 2024Checked 25 Sep0 updates this week

Milestones

Next · Big-animal and disease studies
  1. Mouse lifespan study publishedJan 2024Complete.
  2. Big-animal and disease studiesNowCurrent milestone.

Most important updates

Current obstacles

  • Small study, one labThe mouse result came from a small study and hasn't been repeated by another lab.

Physics limits

  • Viral carriers are one-shot and smallAAV, the harmless virus used as a carrier, holds only about 4.7 kilobases of DNA. The immune system then makes antibodies to its shell, so a second dose usually fails, and many people already carry such antibodies.
  • Leaky switches raise tumour riskDrug-controlled gene switches are never perfectly off. Low-level factor activity over years could push some cells toward tumour-forming stem cells.
  • Not all aging is written in the marksA reset of gene marks leaves mutations, cross-linked proteins and lost cells untouched, so it cannot reverse every part of aging.

How it works

3 parts
Black laboratory mice: the gene therapy extended remaining lifespan in very old mice like these
Black laboratory mice: the gene therapy extended remaining lifespan in very old mice like thesePhoto: Commissioned by Understanding Animal Research · CC BY-SA 4.0 (opens commons.wikimedia.org)
Deliver

Two harmless viruses carry the genes

One AAV virus carries three Yamanaka factors (Oct4, Sox2, Klf4); a second carries the switch that lets the antibiotic doxycycline turn them on.

Pulse

Antibiotic on, antibiotic off

Giving doxycycline on and off switches the factors in short bursts, partly resetting age marks without turning cells into stem cells.

Result

Longer life in very old mice

Mice treated at 124 weeks (about 77 in human years) lived on average 109% longer from that point than untreated mice.

Papers & demos

1 item
  1. Jan 2024paper
    Gene therapy-mediated partial reprogramming extends lifespan in aged mice (Cellular Reprogramming) (opens doi.org)Switching on three Yamanaka factors in very old mice roughly doubled their remaining lifespan.

Update log

2 updates

About Rejuvenate Bio

The team behind OSK partial reprogramming gene therapy

Rejuvenate Bio

Gene therapy, reprogramming in mice, dog hearts

San Diego gene-therapy company co-founded by George Church, working on diseases of aging in animals and people. It's testing a gene therapy for a heart-valve disease in dogs, and reported that reprogramming genes extended the remaining life of very old mice.

rejuvenatebio.com (opens rejuvenatebio.com)Company profile →

Headquarters
United States
Status
Private
Valuation
private
Works in
LongevityCellular reprogramming
Coverage
2 programs · 6 updateslatest 8 Jun 2026checked 25 Sep
People
George Church (opens en.wikipedia.org)Co-founderNoah DavidsohnCo-founder and Chief Scientific Officer
Primer