secwatch.observer — SEC 8-K summary
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Issuer:     Korro Bio, Inc. (KRRO)
CIK:        0001703647
Form:       8-K
Filed at:   2026-10-22T11:04:13+00:00
Accession:  0001193125-26-428306
Event type: other_material
Sentiment:  positive
Materiality: 0.60
Item codes: 8.01, 9.01
LLM model:  deepseek-v4.1-flash:cloud@v2

Korro's KRRO-111 shows 96% SERPINA1 editing, 95% liver Z-AAT cut; 1H 2027 filing planned
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- In NSG-PiZ mice, repeat-dose KRRO-111 reached 96% SERPINA1 mRNA editing, with M-AAT at 93% of circulating AAT and total AAT of 172 μM (~6-fold vs vehicle) at Day 57.
- In immunocompetent C57BL/6-PiZ mice, KRRO-111 reduced whole-liver Z-AAT by 95% versus vehicle at Day 57, measured by LC-MS/MS.
- Single-dose C57BL/6-PiZ: up to 91% editing and M-AAT up to 88% of total AAT, detectable through Day 42; EC50 ~1 nM, up to 98% editing in mouse and human hepatocytes.
- KRRO-111 is a subcutaneous GalNAc-conjugated oligonucleotide using ADAR to correct the pathogenic SERPINA1 transcript; Korro expects a regulatory submission in 1H 2027.
- CSO Loïc Vincent said the dual profile restores functional M-AAT while cutting toxic Z-AAT; CEO Ram Aiyar said Korro plans to advance KRRO-111 into the clinic in 1H 2027.

Source:
  EDGAR index:    https://www.sec.gov/Archives/edgar/data/1703647/000119312526428306/0001193125-26-428306-index.htm
  Primary doc:    https://www.sec.gov/Archives/edgar/data/1703647/000119312526428306/krro-20261022.htm
  HTML page:      https://secwatch.observer/filing/0001193125-26-428306

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