Skip to main content

Greenwich LifeSciences, Inc.

corporate_fare Company Profile

Greenwich LifeSciences, Inc.

GLSI·NASDAQ·Life Sciences·CIK 0001799788

Greenwich LifeSciences, Inc. is a clinical-stage biopharmaceutical company focused on developing an immunotherapy to prevent breast cancer recurrences. The company's primary product candidate is GLSI-100, which is currently being evaluated in a Phase III clinical trial called Flamingo-01. GLSI-100 combines GP2, a 9 amino acid transmembrane peptide derived from the HER2/neu protein, with GM-CSF. The HER2/neu protein is expressed in 75% of breast cancers at low (1+), intermediate (2+), and high (3+ or over-expressor) levels. The Flamingo-01 trial is designed to assess the safety and efficacy of GLSI-100 in HER2/neu positive patients who have residual disease or a high-risk pathologic complete response at surgery, and who have completed both neoadjuvant and postoperative adjuvant trastuzumab-based treatment. Greenwich LifeSciences is expanding Flamingo-01 into Europe, with plans to open up to 150 sites globally. GP2 works by eliciting a targeted immune response against HER2/neu-expressing cancers. GM-CSF, or recombinant human granulocyte macrophage colony-stimulating factor (sargramostim, Leukine®), acts as an immunoadjuvant, enhancing the immune response. GLSI-100 is administered via an intradermal injection, mixing GP2 peptide and GM-CSF at the time of administration. GM-CSF is available in lyophilized form exclusively from one manufacturer. While GM-CSF is approved for sale in the U.S. by the FDA, it is available in other countries on a named patient basis through a specialized company.

Greenwich LifeSciences, Inc. (NASDAQ:GLSI) is a publicly traded company in the Life Sciences sector. Wiseek has independently scored 9 items for GLSI at importance 7 or higher on its 1–10 market-impact scale. Its most recent item scored 7 or higher is dated 2026-08-11, rated 8/10. Across its 9 most recent items scored 7 or higher, the top rating is 9/10, with 8 rated 8 or above. Recent SEC coverage for GLSI spans 10-Q, 10-K.

Recent high-impact activity:

  • Greenwich LifeSciences Q2 Loss Widens to $3.95M; Cash at $8.88M, Going Concern Warning Reiterated
  • UK Regulators Approve FLAMINGO-01 Expansion, Adding 5-10 Sites
  • EMA Greenlights Combined HLA Enrollment in FLAMINGO-01, Doubling Potential Market
  • Preliminary Phase III Data Shows 70-80% Recurrence Reduction for Greenwich LifeSciences' GP2
  • Greenwich LifeSciences Q1 Net Loss Doubles to $5.66M, Zero Revenue Persists

Financial Snapshot

Fiscal year ended December 31, 2025
Net Income
-$19.36M
Diluted EPS
-$1.43
Op. Cash Flow
-$9.91M
Operating Income
-$19.45M
Cash & Equivalents
$6.18M
Debt / Equity
0.00×
Shares Outstanding
14.3M sh
Source: 10-K · filed 2026-06-01 · accession 0001493152-26-026651

Short Interest & Short Volume

19.78 days to cover

FINRA reported short interest of 1,631,150 shares in GLSI as of the September 15, 2026 settlement, a 1.8% decrease from the prior period — about 19.8 days to cover at its recent average daily volume. On October 2, 2026, 80.7% of GLSI volume reported to FINRA trade-reporting facilities was marked short.

Short interest (bi-monthly positions)1,631,150 shares as of September 15, 2026
Change vs prior period▼ 1.8%
Days to cover19.78 at avg daily volume of 82,446
Daily short volume (FINRA facilities)80.7% of 53,613 shares on October 2, 2026
5-day average short volume78.8%

Daily short sale volume covers trades reported to FINRA trade-reporting facilities and is not the same as short interest (bi-monthly reported positions). Source: FINRA — FINRA is the owner and source of this short interest and short sale volume data; it may not be redistributed.

Browse all tickers starting with G →
$16.98
52-week range · as of 2026-08-11 $7.78 – $34.1
Market cap
$249.24M
Volume
175.4K (1.4× avg)
3-mo avg 126.5K
Live data · 2026-10-03 11:47 UTC · Market closed

show_chartPrice Chart

Loading chart...

feed GLSI - Latest Insights

GLSI
Aug 11, 2026, 4:30 PM EDT
Filing Type: 10-Q
Importance Score:
8
Price at Filing: $15.55
Real-time Price: $16.98 info
Change: +$1.43 (+9%) info
Market Cap: $249.236M info
GLSI
Jul 22, 2026, 6:00 AM EDT
Source: GlobeNewswire
Importance Score:
7
Price at Filing: $14.66
Real-time Price: $16.98 info
Change: +$2.32 (+16%) info
Market Cap: $249.236M info
GLSI
Jul 16, 2026, 7:30 AM EDT
Source: GlobeNewswire
Importance Score:
8
Price at Filing: $20.69
Real-time Price: $16.98 info
Change: -$3.71 (-18%) info
Market Cap: $249.236M info
GLSI
Jul 09, 2026, 6:00 AM EDT
Source: GlobeNewswire
Importance Score:
8
Price at Filing: $18.35
Real-time Price: $16.98 info
Change: -$1.37 (-7%) info
Market Cap: $249.236M info
GLSI
Jun 04, 2026, 6:11 AM EDT
Source: Wiseek News
Importance Score:
8
Price at Filing: $23.70
Real-time Price: $16.98 info
Change: -$6.72 (-28%) info
Market Cap: $249.236M info
GLSI
Jun 03, 2026, 6:19 PM EDT
Filing Type: 10-Q
Importance Score:
8
Price at Filing: $23.61
Real-time Price: $16.98 info
Change: -$6.63 (-28%) info
Market Cap: $249.236M info
GLSI
Jun 01, 2026, 4:56 PM EDT
Filing Type: 10-K
Importance Score:
9
Price at Filing: $27.62
Real-time Price: $16.98 info
Change: -$10.64 (-39%) info
Market Cap: $249.236M info
GLSI
Mar 17, 2026, 6:00 AM EDT
Source: GlobeNewswire
Importance Score:
9
Price at Filing: $29.80
Real-time Price: $16.98 info
Change: -$12.82 (-43%) info
Market Cap: $249.236M info
GLSI
Mar 03, 2026, 6:00 AM EST
Source: GlobeNewswire
Importance Score:
8
Price at Filing: $26.75
Real-time Price: $16.98 info
Change: -$9.77 (-37%) info
Market Cap: $249.236M info
Research tools: Filing Impact Index Dilution Tracker Split Calendar Open Datasets