JUN_01 by Junevity: status and timeline

Milestones

Next · First-in-human trial start

Junevity founded from UCSF research2023Complete.
PNAS publication on transcription-factor reprogrammingJan 2026Complete.
Seed funding expanded to $20 millionDec 2025Complete.
First-in-human trial startTarget Q3 2026Not yet reached.

Upcoming

Q3 2026First-in-human trial start (next)

Current obstacles

Getting siRNA into the right cellsLarge, charged molecules struggle to reach liver and fat cells in sufficient concentration.
Safety and immune toleranceChronic siRNA dosing may trigger immune responses. Long-term tolerability in humans remains unproven.

Physics limits

siRNA molecules are unstableRNA is fragile and is rapidly degraded by cellular RNases and serum nucleases. Chemical modifications and delivery vehicles are needed to keep siRNA intact long enough to work.
Transcription factors are difficult targetsTranscription factors are in the nucleus and present in low copy numbers. siRNA designed to knock them down must achieve high potency and specificity simultaneously.

How it works

3 parts

Identify

Find transcription factor from disease data

ML identifies a transcription factor whose dysregulation drives obesity or diabetes.

Design

Design siRNA to silence the target

siRNA sequence matches the target gene, allowing the cell's RNAi machinery to silence it.

Restore

Network recovers its normal state

Silencing the master regulator restores downstream genes to normal, restoring metabolic health.

Spec sheet

Spec	JUN_01
Target dosing frequency	Twice per year^R (reported)
Preclinical weight loss (in studies)	Robust reduction^R (reported)
Lean mass preservation	Maintained in preclinical^R (reported)
Insulin sensitivity improvement	Improved in preclinical models^R (reported)

^R reported by the company

Papers & demos

1 item

Jan 2026paper
Single-target repression can reprogram cellular aging networks (opens pnas.org)Founding research showing that silencing one transcription factor restores gene networks in human aging cell models, published in PNAS.

About Junevity

The team behind JUN_01

Junevity

RESET platform, siRNA, cellular reprogramming, transcription factors

Junevity uses siRNA to reprogram cell networks by silencing transcription factors. The company was founded from UCSF research in 2023 and is developing therapeutics for obesity and metabolic disease, with lead programs expected to enter clinical trials in H2 2026.

Junevity silences transcription factors with siRNA to reprogram cell networks. Founders' PNAS study showed restoration of aging cells.
Lead JUN_01 targets obesity and diabetes with twice-yearly dosing. Human trials planned H2 2026.

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

Founded: 20233 yrs
Headquarters: United States
Status: Private
Valuation: private
Raised: $20M2 rounds
Last round: Seed (expanded) · $10MDec 2025
Works in: LongevityCellular reprogramming
Coverage: 1 program · 4 updateslatest 1 Jan 2026checked 10 Oct
Lead investors: Goldcrest CapitalGodfrey Capital
Partners: University of California, San Francisco (opens ucsf.edu)
People: John Hoekman (opens junevity.com)Co-founderJanine Sengstack (opens junevity.com)Co-founder and Chief Scientific OfficerRob Cahill (opens junevity.com)Co-founderHao Li (opens junevity.com)Co-founder

Spec

JUN_01

Target dosing frequency

Twice per year^R (reported)

Preclinical weight loss (in studies)

Robust reduction^R (reported)

Lean mass preservation

Maintained in preclinical^R (reported)

Insulin sensitivity improvement

Improved in preclinical models^R (reported)