---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-414118"
form_type: "8-K"
ticker: "KRRO"
cik: "0001703647"
company_name: "Korro Bio, Inc."
filed_at: "2026-10-05T20:10:13+00:00"
generated_at: "2026-10-12T14:50:19.080028+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# Korro Bio doses first cohort in Phase 1/2 ANCHOR trial of KRRO-121 for urea cycle disorders

## Summary
- First cohort of healthy volunteers received a single 2mg/kg dose of KRRO-121, a GalNAc-conjugated RNA-editing oligonucleotide (REO) targeting hyperammonemia in UCD and hepatic encephalopathy.
- ANCHOR Part 1: placebo-controlled SAD in up to 30 healthy volunteers across up to 5 cohorts, then MAD in up to 20 subjects across 2 cohorts; enrollment is in Australia (NCT07773246).
- ANCHOR Part 2: Phase 2 multiple-dose study in up to 15 UCD patients across all UCD genotypes, subject to regulatory approval.
- Dosing in UCD patients expected to begin in the first half of 2027, with an interim readout expected in the second half of 2027.
- CEO Ram Aiyar said KRRO-121 blunted ammonia excursions in multiple preclinical studies across different mutations; trial first aims to establish safety, then activity.

## SEC filing metadata
- accession: 0001193125-26-414118
- form_type: 8-K
- ticker: KRRO
- cik: 0001703647
- company_name: Korro Bio, Inc.
- filed_at: 2026-10-05T20:10:13+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1703647/000119312526414118/0001193125-26-414118-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1703647/000119312526414118/krro-20261005.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-414118
- JSON: https://secwatch.observer/filing/0001193125-26-414118.json
- Plain text: https://secwatch.observer/filing/0001193125-26-414118.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.