YOLT-101 by YolTech Therapeutics: status and timeline

Milestones

Next · Phase II development (planned)

FDA IND clearanceJun 2025Complete.
NMPA IND approval in ChinaJul 2025Complete.
Phase I interim data generatedApr 2025Complete.
Phase II development (planned)Target Q4 2026Current milestone.

Most important updates

FDA grants IND clearance for YOLT-101, first in vivo base editor for cardiovascular disease in the U.S.Jun 2025
YOLT-101 Phase I interim data show 52% LDL reduction in investigator-led trialApr 2025

Upcoming

Q4 2026Phase II development (planned) (next)
Q4 2026Expansion to Phase II trials

Current obstacles

Immune responses to LNP or base editor proteinImmune system may recognize and neutralize the therapy or damage liver cells.
Off-target editing at similar DNA sequencesBase editors may edit related genes with similar sequences, causing unintended changes.

Physics limits

LNP delivery capacityLipid nanoparticles carry only a small payload (typically 20–50 kb of genetic material). Complex genes or multi-protein therapies cannot fit, limiting the types of edits possible.
Liver is the only accessible organ via IV LNPCurrent LNPs accumulate in the liver and spleen. Editing other organs (muscle, brain, heart) requires new delivery methods.

How it works

3 parts

Base editing

Flipping one DNA letter

Base editor protein flips one DNA letter in PCSK9, disrupting it without cutting DNA.

In vivo therapy

Editing inside the body

LNP delivers editor mRNA intravenously. Liver cells translate it into editor protein that edits PCSK9.

Permanent effect

A permanent change in one cell division

Edited PCSK9 remains disrupted in liver cells. Rare cell division means lifelong effect.

Spec sheet

Spec	YOLT-101
LDL-C reduction at 4 months	50.4%^R (reported)
PCSK9 protein reduction at 4 months	75.8%^R (reported)
Route of administration	Intravenous, single dose^R (reported)
Highest dose tested	0.6 mg/kg^R (reported)

^R reported by the company

Update log

2 updates

Jun 2025

Major: FDA grants IND clearance for YOLT-101, first in vivo base editor for cardiovascular disease in the U.S.PressRegulatory

Apr 2025

Major: YOLT-101 Phase I interim data show 52% LDL reduction in investigator-led trialOtherResearch

About YolTech Therapeutics

The team behind YOLT-101

YolTech Therapeutics

In vivo base editing, PCSK9, LNP delivery, gene medicine

YolTech is a Shanghai-based gene medicine company focused on in vivo base editing therapies. Founded in 2021, YolTech develops genome editing and LNP delivery platforms to treat cardiovascular and metabolic diseases with single-dose therapies.

YOLT-101, a PCSK9 base editor, showed 50% LDL-C and 76% PCSK9 reduction in Phase I trials.
Raised $115M across Series B and C funding through May 2026.
First in vivo base editor for cardiovascular disease to enter clinical trials in China and the U.S.

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

Founded: 20215 yrs
Headquarters: China
Status: Private
Valuation: $400Mest. privateMay 2026estimate
Raised: $115M2 rounds
Last round: Series C · $70MMay 2026
Works in: BiotechGene editing & therapy
Coverage: 1 program · 4 updateslatest 1 May 2026checked 10 Oct
Lead investors: Loyal Valley CapitalAstraZeneca-CICC healthcare investment fund
Partners: Renji Hospital, Shanghai Jiao Tong University
People: Yuxuan Wu (opens yoltx.com)Co-founder and CEO

Spec

YOLT-101

LDL-C reduction at 4 months

50.4%^R (reported)

PCSK9 protein reduction at 4 months

75.8%^R (reported)

Route of administration

Intravenous, single dose^R (reported)

Highest dose tested

0.6 mg/kg^R (reported)