Korro Bio, Inc.
KRRO · Pharmaceutical Preparations · 14.4M shares · +491%/yr ↑ shares · EDGAR filings ↗
Reference price $14.60 · est. market cap ~$211M — last insider sale, 2026-06-24 (estimated from the dated SEC Form 4 price × shares outstanding — not a live quote)
Grade
D44Clinical/early-stage biotech — RNA-editing clinical, funded.
Strengths
- Liquidity — current ratio 6.9 (69th)
Risks
- Pre-revenue, deep losses — per metrics
- Pre-revenue/clinical-stage — history of losses & need for capital per risk factors
- Binary clinical & funding risk — per 10-K
Notable findings
- Chronic dilutionShare count +491%/yr over 2y (dilution)
- Cash burnNegative free cash flow (-79.1M)
- Fund exitedNotable fund(s) exited this quarter: VANGUARD GROUP INC
- Net lossNet loss (net margin -1834.5%)
- Insider buyingInsider buying — 10 open-market buy(s) by 10 insider(s) (cluster of 10 insiders, ~$21M, last 6mo) Form 4 ↗
- Insider sellingInsider selling — 15 open-market sale(s) by 6 insider(s) (cluster of 6 insiders, ~$3M, last 6mo) Form 4 ↗
- Revenue declineRevenue -100.0% YoY
- Notable holderHeld by 5 notable fund(s): CITADEL ADVISORS LLC, STATE STREET CORP, RENAISSANCE TECHNOLOGIES LLC +2 more (as of 2026-03-31)
Quarterly revenue
Last 4 quarters · from SEC filings.
Key metrics
Operating margin
-1906.4%
Net margin
-1834.5%
Return on assets
-103.3%
Revenue growth (QoQ)
-100.0%
Current ratio
6.9×
Free cash flow
-$79M
Cash & investments
$85M
Cash runway
4q
Stock comp / revenue
119.8%
Insider transactions · last 18 months
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| 2026-06-24 | FORMELA JEAN FRANCOIS | Sell | 114 | $14.98 |
| 2026-06-24 | FORMELA JEAN FRANCOIS | Sell | 41K | $14.60 |
| 2026-06-24 | FORMELA JEAN FRANCOIS | Sell | 666 | $14.98 |
| 2026-06-24 | FORMELA JEAN FRANCOIS | Sell | 7.0K | $14.60 |
| 2026-06-23 | FORMELA JEAN FRANCOIS | Sell | 102K | $14.25 |
| 2026-06-23 | FORMELA JEAN FRANCOIS | Sell | 17K | $14.25 |
| 2026-06-22 | FORMELA JEAN FRANCOIS | Sell | 3.4K | $13.95 |
| 2026-06-22 | FORMELA JEAN FRANCOIS | Sell | 580 | $13.95 |
| 2026-06-16 | Chappell Todd | Sell | 3.2K | $10.83 |
| 2026-06-16 | Vincent Loic A | Sell | 3.4K | $10.83 |
| 2026-06-16 | Cerio Jeffrey | Sell | 6.6K | $10.83 |
| 2026-06-16 | Dolan Oliver | Sell | 3.4K | $10.83 |
| 2026-05-29 | Aiyar Ram | Sell | 15K | $12.98 |
| 2026-05-28 | FORMELA JEAN FRANCOIS | Sell | 2.4K | $13.95 |
| 2026-05-28 | FORMELA JEAN FRANCOIS | Sell | 419 | $13.95 |
| 2026-05-26 | Aiyar Ram | Grant | 50K | $12.33 |
| 2026-03-31 | Lynx1 Capital Management LP | Buy | 520 | $10.60 |
| 2026-03-10 | Yang Rick | Buy | 207K | $11.11 |
| 2026-03-10 | SANDELL SCOTT D | Buy | 207K | $11.11 |
| 2026-03-10 | New Enterprise Associates 17, L.P. | Buy | 207K | $11.11 |
| 2026-03-10 | Behbahani Ali | Grant | 207K | $11.11 |
| 2026-03-10 | Chang Carmen | Buy | 207K | $11.11 |
| 2026-03-10 | BASKETT FOREST | Buy | 207K | $11.11 |
| 2026-03-10 | Mathers Edward T | Buy | 207K | $11.11 |
| 2026-03-10 | Walker Paul Edward | Buy | 207K | $11.11 |
| 2026-03-10 | Makhzoumi Mohamad | Buy | 207K | $11.11 |
| 2026-03-10 | Florence Anthony A. Jr. | Buy | 207K | $11.11 |
| 2026-02-02 | Aiyar Ram | Grant | 40K | — |
| 2025-12-15 | Chappell Todd | Grant | 20K | — |
| 2025-12-15 | Vincent Loic A | Grant | 22K | — |
| 2025-12-15 | Cerio Jeffrey | Grant | 42K | — |
| 2025-12-15 | Dolan Oliver | Grant | 21K | — |
All non-derivative Form 4 activity (SEC), newest first.
Clinical trials
| Trial | Title | Phase | Status | Primary completion |
|---|---|---|---|---|
| NCT06677307 ↗ | A Phase 1/2a, Single- and Multiple-dose Escalation Study of KRRO-110 Alpha-1 Anti-trypsin Deficiency, AATD | PHASE1/PHASE2 | Terminated | 2025-10-31 |
Source: ClinicalTrials.gov (U.S. NIH) · active studies first.
Notable events (8-K)
| Date | Items | |
|---|---|---|
| 2026-06-11 | Shareholder vote | filing ↗ |
| 2026-05-19 | OtherExhibits | filing ↗ |
| 2026-05-07 | ResultsExhibits | filing ↗ |
| 2026-03-12 | ResultsExhibits | filing ↗ |
| 2026-03-09 | Material agreementResults3.02Reg FDExhibits | filing ↗ |
| 2026-01-27 | OtherExhibits | filing ↗ |
| 2026-01-15 | OtherExhibits | filing ↗ |
| 2025-12-18 | Exec/director changeExhibits | filing ↗ |
Recent filings
| Form | Filed | Period | Accession |
|---|---|---|---|
| 8-K | 2026-06-11 | 2026-06-10 | 0001193125-26-267741 ↗ |
| 8-K | 2026-05-19 | 2026-05-19 | 0001193125-26-229610 ↗ |
| 8-K | 2026-05-07 | 2026-05-07 | 0001193125-26-210291 ↗ |
| 10-Q | 2026-05-07 | 2026-03-31 | 0001193125-26-210303 ↗ |
| 10-K | 2026-03-12 | 2025-12-31 | 0001193125-26-104156 ↗ |
| 8-K | 2026-03-12 | 2026-03-12 | 0001193125-26-104135 ↗ |
| 8-K | 2026-03-09 | 2026-03-09 | 0001193125-26-097575 ↗ |
| 8-K | 2026-01-27 | 2026-01-27 | 0001193125-26-023436 ↗ |
| 8-K | 2026-01-15 | 2026-01-15 | 0001193125-26-014087 ↗ |
| 8-K | 2025-12-18 | 2025-12-15 | 0001193125-25-324795 ↗ |
| 10-Q | 2025-11-12 | 2025-09-30 | 0001193125-25-277572 ↗ |
| 8-K | 2025-11-12 | 2025-11-07 | 0001193125-25-277556 ↗ |