Korro Bio (KRRO)
Develops RNA-editing therapeutics around OPERA and GalNAc-delivered liver programs.
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Works as a research-stage RNA-editing biotech, using OPERA oligonucleotides to edit native mRNA and build genetic medicines. Its focus has shifted toward GalNAc-delivered liver programs led by KRRO-121, while no RNA-editing product is approved and its Novo Nordisk collaboration is paused.
Develops genetic medicines through OPERA, an oligonucleotide-promoted RNA-editing platform designed to edit native mRNA rather than DNA. The current portfolio is preclinical, led by KRRO-121 for hyperammonemia in urea cycle disorders and hepatic encephalopathy, with additional GalNAc liver work after the KRRO-110 pivot.
Operates from Cambridge, Massachusetts as a single-segment biotech focused on discovery, development, and potential commercialization. Execution centers on selecting delivery formats, translating RNA edits into functional protein effects, and advancing wholly owned programs alongside collaboration work.
No RNA-editing therapeutic product is approved in the United States or Europe. The business depends on clinical validation of preclinical programs, continued financing, and the Novo Nordisk collaboration, which is in a scheduled pause.
Company facts
Target rangeAs of Sep 22, 2026
Latest analyst notes
| Date | Firm | Action | Prior | Current |
|---|---|---|---|---|
| May 19, 2026 | H.C. Wainwright | Target | Target: $20 | Target: $15 |
| Mar 13, 2026 | Cantor Fitzgerald | Reiterate | Rating: —Target: $21 | Target: $22 |
| Mar 13, 2026 | Raymond James | Upgrade | Target: $18 | Target: $23 |
| Feb 19, 2026 | Clear Street | Upgrade | ||
| Feb 18, 2026 | Raymond James | Target | Target: — | Target: $18 |
EPSReportedEstimate
RevenueReportedEstimate
Balance sheet, Jun 30, 2026Cash & short-term investments $115.0M · Total debt $42.2M · Total assets $163.4M · Shareholders' equity $103.2M
- Revenue
- $0
- Operating income
- −$20.1M
- Net income
- −$18.9M
No dividends on record.
| Institutions | ≈ 98.13% | 14.45M shares | |
|---|---|---|---|
| 112 holders · as of Jun 30, 2026 · largest filers plus last quarter's tail | |||
| Insiders | 16.35% | 2.41M shares | |
| 7 holders · as of Sep 15, 2026 | |||
| Adds to | 114.48% | ||
14.73M company shares as of Sep 23, 2026 · institutions as of Jun 30, 2026 · holders as of their latest filing
Two share counts disagree (14.73M in the company's Sep 23, 2026 report, 9.95M elsewhere); stakes use the report.
This quarter's institutional total failed a plausibility check; shown: the largest filers plus last quarter's remainder.
These groups come from separate filings that can overlap, so they add to 114.48%; nothing is left for Other.
Top shareholders13F · 13D/G · Form 4
| Holder | Stake | Shares | Date |
|---|---|---|---|
Lynx1 Capital Management LPInstitution | 10.45% | 1.54M | as of Jun 30, 2026 |
Venrock Healthcare Capital Partners III, L.P.Institution | 10.11% | 1.49M | filed Mar 17, 2026 |
Ali Behbahani1,2Insiderdirector, 10 percent owner | 9.89% | 1.46M | filed Mar 12, 2026 |
Nea Management Company, LLCInstitution | 8.81% | 1.30M | as of Jun 30, 2026 |
VR Adviser, LLCInstitution | 6.86% | 1.01M | as of Jun 30, 2026 |
- Ali Behbahani's transaction reports restate only vehicles that traded; the 2026 ownership statement (1.46M) is used instead.
- Ali Behbahani reports a block also reported by another filer; it is counted once, under that filer.
Insider tradesForm 4
| Date | Insider | Role | Shares | Avg price |
|---|---|---|---|---|
| Sep 14, 2026 | Jean Francois Formela | director | −38,490 | $14.12 |
| Sep 11, 2026 | Jean Francois Formela | director | −10,200 | $13.99 |
| Sep 11, 2026 | Oliver Dolan | officer: Senior Vice President, Finance | −5 | $13.72 |
| Sep 9, 2026 | Oliver Dolan | officer: Senior Vice President, Finance | −6 | $13.60 |
| Sep 8, 2026 | Oliver Dolan | officer: Senior Vice President, Finance | −7,347 | $13.51 |
- Wave Life Sciences
Direct RNA-editing peer in AATD and GalNAc liver programs
- ProQR Therapeutics
ADAR RNA-editing platform peer across liver and CNS programs
- Beam Therapeutics
AATD and liver genetic-medicine peer using base editing
- Arrowhead Pharmaceuticals
RNAi peer in AATD liver disease and targeted delivery
- Alnylam Pharmaceuticals
Commercial RNAi leader with GalNAc liver-delivery overlap
- Ionis Pharmaceuticals
Antisense oligonucleotide peer in RNA-targeted medicines
Compare
| Company | Price | Change | |||||
|---|---|---|---|---|---|---|---|
| Korro Bio | $9.93 | −3.96% | $102.9M | — | — | 43.2 | +2.7% |
| Wave Life Sciences | $3.99 | −8.39% | $857.2M | — | — | 13.1 | −73.9% |
| ProQR Therapeutics | $1.72 | −9.74% | $200.1M | — | — | 9.4 | +122.6% |
| Beam Therapeutics | $24.41 | −5.88% | $2.67B | — | — | 17.1 | −94.2% |
| Arrowhead Pharmaceuticals | $67.20 | −6.49% | $10.12B | — | — | 15.1 | +171.0% |
| Alnylam Pharmaceuticals | $246.37 | −2.10% | $33.67B | 42.5 | 29.3 | 7.0 | +66.9% |
| Ionis Pharmaceuticals | $44.47 | −2.80% | $7.60B | — | — | 8.7 | −40.7% |
| Median | 42.5 | 29.3 | 11.3 | +13.1% |








