GLSI Stock Summary and Trading Ideas (Greenwich Lifesciences | NASDAQ:GLSI)

Greenwich LifeSciences Inc a clinical-stage biopharmaceutical company focused on its Phase III clinical trial, Flamingo-01, which is evaluating GLSI-100, an immunotherapy to prevent breast cancer recurrences. GP2 is a 9 amino acid transmembrane peptide of the HER2/neu protein, a cell surface receptor protein that is expressed in a variety of common cancers, including expression in 75 percent of breast cancers at low (1+), intermediate (2+), and high (3+ or over-expressor) levels. The combination of GP2 + GM-CSF is called GLSI-100. The company is currently expanding Flamingo-01 into Europe with plans to open up to 150 sites globally.

Greenwich Lifesciences trades on the NASDAQ stock market under the symbol GLSI.

As of June 18, 2026, GLSI stock price declined to $23.38 with 85,214 million shares trading.

GLSI has a beta of 2.26, meaning it tends to be more sensitive to market movements. GLSI has a correlation of 0.11 to the broad based SPY ETF.

GLSI has a market cap of $312.55 million. This is considered a Small Cap stock.

In the last 3 years, GLSI traded as high as $34.10 and as low as $7.58.

The top ETF exchange traded funds that GLSI belongs to (by Net Assets): VTI, IWM, VXF, IWO, VTWO.

GLSI has outperformed the market in the last year with a return of +162.1%, while the SPY ETF gained +26.9%. However, in the most recent history, GLSI shares have underperformed the stock market with its stock returning -12.5% in the last 3 month period and -1.2% for the last 2 week period, while SPY has returned +13.5% and -1.1%, respectively.

GLSI support price is $22.58 and resistance is $25.40 (based on 1 day standard deviation move). This means that using the most recent 20 day stock volatility and applying a one standard deviation move around the stock's closing price, stastically there is a 67% probability that GLSI shares will trade within this expected range on the day.