About Estuary Bio
Estuary develops treatments for people with serious kidney diseases. It is building gene-based medicines for autosomal dominant polycystic kidney disease, or ADPKD.
The Yale spinout is based in Menlo Park, California. Wayne Sackett serves as chief executive officer.
Funding Rounds (SEC Form D)
| First sale | Filed with SEC | Amount sold | Investors | Avg. check | Terms | Filing |
|---|---|---|---|---|---|---|
| Jul 1, 2026 | Oct 16, 2026 | $40,654,685of $103.6M target | 25 | $1.6M | EquityRule 506(b) | Form D ↗ |
First sale is the date the first investor in the offering committed to invest. Companies must file Form D within 15 days of that date, so filing dates run later.
Rounds announced by Estuary Bio
What the company said publicly about its funding. Announced amounts can differ from Form D figures: an announcement can combine several closings, and some money is raised without a Form D.
| Announced | Round | Amount | Investors | Source |
|---|---|---|---|---|
| Oct 16, 2026 | Series A | $93 million | RA Capital Management (lead) | BioWorld ↗ |
Why Investors Backed Estuary Bio
Estuary is developing gene therapies for serious kidney diseases. Its public launch brought $103 million in financing. That capital is intended to support programs for polycystic kidney disease.
Progress so far
The company's candidates have not received regulatory approval. Their safety and efficacy remain unestablished.
We wrote this summary from public statements by Estuary Bio and its investors. It is not investment advice.
Estuary Bio in the News
- 'I want to zig when others are zagging': A Bay Area biotech startup targets a devastating kidney disease
- Biogen-backed Estuary nabs $93M for kidney disease
- Estuary Biotherapeutics launches to treat kidney disease with gene therapies
- Estuary emerges with $103M for kidney disease gene therapies
- Estuary Biotherapeutics launches with targeted gene therapies for ADPKD
- ADPKD Gene Therapy Development at Newly Launched Estuary Biotherapeutics
Leadership Team
Executive officers and directors listed on Estuary Bio's Form D filed Oct 16, 2026.