Greenwich LifeSciences (GLSI)
Runs a single Phase III trial for a peptide vaccine preventing HER2-positive breast cancer recurrence.
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Develops a single therapeutic candidate, GLSI-100, a peptide-based immune vaccine combining GP2 with GM-CSF designed to prevent recurrence in HER2-positive breast cancer after standard treatment. The company runs a global Phase III trial spanning roughly forty clinical sites across the US and Europe and has not yet generated product revenue, funding operations through equity issuance.
Runs on a single pipeline asset, GLSI-100, a peptide vaccine pairing the GP2 antigen with the adjuvant GM-CSF, aimed at preventing recurrence in HER2-positive breast cancer after standard treatment. The vaccine originated at a US military-linked research foundation and was in-licensed before the company's listing.
The current trial, FLAMINGO-01, is a global randomized Phase III study run mostly through academic and cooperative-group site networks across the US and Europe rather than an in-house clinical organization. It carries FDA Fast Track designation for the HLA-positive patient subgroup, and a parallel open-label arm for patients outside that subgroup has completed enrollment.
Ownership is concentrated among management and directors under an extended post-IPO lock-up, and the business remains pre-revenue, funding trials through periodic equity issuance rather than product sales. Commercial-scale manufacturing has begun, supplying ongoing dosing across the US site network.
Company facts
Target rangeAs of Sep 22, 2026
Latest analyst notes
| Date | Firm | Action | Prior | Current |
|---|---|---|---|---|
| Dec 30, 2025 | H.C. Wainwright | Target | Target: — | Target: $50 |
EPSReportedEstimate
RevenueReportedEstimate
Balance sheet, Jun 30, 2026Cash & short-term investments $8.9M · Total debt $0 · Total assets $8.9M · Shareholders' equity $3.1M
- Revenue
- $0
- Operating income
- −$4.0M
- Net income
- −$3.9M
No dividends on record.
| Institutions | 11.61% | 1.70M shares | |
|---|---|---|---|
| 60 holders · as of Jun 30, 2026 | |||
| Insiders | 78.15% | 11.47M shares | |
| 4 holders · as of Jul 30, 2026 | |||
| Other | 10.24% | 1.50M shares | |
| remainder | |||
14.68M company shares as of Sep 23, 2026 · institutions as of Jun 30, 2026 · holders as of their latest filing
Top shareholders13F · 13D/G · Form 4
| Holder | Stake | Shares | Date |
|---|---|---|---|
Snehal Patel1Insiderdirector, 10 percent owner, officer: CEO and CFO | 56.42% | 7.78M | filed Jul 30, 2026 |
WeinerInsider | 15.70% | 2.30M | filed Jun 22, 2022 |
David McWilliamsInsiderdirector | 4.23% | 620,301 | filed Dec 16, 2021 |
BlackRock, Inc.Institution | 3.31% | 485,854 | as of Jun 30, 2026 |
Vanguard Capital Management LLCInstitution | 1.90% | 278,190 | as of Jun 30, 2026 |
- Snehal Patel's transaction reports restate only vehicles that traded; the 2020 ownership statement (7.78M) plus the 504.0K net shares acquired since is used instead.
Insider tradesForm 4
| Date | Insider | Role | Shares | Avg price |
|---|---|---|---|---|
| Jul 28, 2026 | Snehal Patel | director, 10 percent owner, officer: CEO and CFO | +1,500 | $13.59 |
| Jul 29, 2026 | Snehal Patel | director, 10 percent owner, officer: CEO and CFO | +700 | $13.10 |
| Jul 27, 2026 | Snehal Patel | director, 10 percent owner, officer: CEO and CFO | +1,500 | $13.62 |
| Jul 23, 2026 | Snehal Patel | director, 10 percent owner, officer: CEO and CFO | +2,500 | $13.14 |
| Jul 24, 2026 | Snehal Patel | director, 10 percent owner, officer: CEO and CFO | +1,100 | $12.88 |
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Compare
| Company | Price | Change | |||||
|---|---|---|---|---|---|---|---|
| Greenwich LifeSciences | $17.51 | −10.11% | $285.9M | — | — | — | — |
| AstraZeneca (ADR) | $163.78 | −2.73% | $261.12B | 25.3 | 15.4 | 4.3 | +6.4% |
| Puma Biotechnology | $9.26 | −5.70% | $499.8M | 19.0 | — | 2.2 | +14.8% |
| BioNTech (ADR) | $98.70 | −2.15% | $25.34B | — | — | 8.4 | −60.7% |
| Moderna | $183.24 | +0.37% | $72.44B | — | — | 32.5 | +2.1% |
| Novartis (ADR) | $142.72 | +1.02% | $268.53B | 21.3 | 15.2 | 4.8 | +0.9% |
| Median | 21.3 | 15.3 | 4.8 | +2.1% |