Greenwich LifeSciences Advances Phase 3 FLAMINGO-01 Trial for Breast Cancer Immunotherapy GLSI-100

Greenwich LifeSciences, Inc. (NASDAQ: GLSI) provided an update on its Phase 3 FLAMINGO-01 trial evaluating GLSI-100, an immunotherapy designed to prevent breast cancer recurrence. The company announced that the study's Data Safety Monitoring Board recommended the trial continue without modification following its May 2026 review. Regulatory authorities in the U.S. and Europe have supported planned protocol changes that include expanding enrollment to as many as 2,000 patients, increasing enrollment rates by including all HLA types, and maintaining enrollment through interim analyses to strengthen the study design and increase the probability of success.

Greenwich LifeSciences stated that more than 1,500 patients have been screened across approximately 170 to 180 clinical sites in 11 countries, with plans to expand into additional European markets as well as the U.K. and Canada. The company also reported preliminary data from the fully enrolled open-label non-HLA-A*02 arm continues to show a 70% to 80% reduction in breast cancer recurrence following the primary immunization series, while maintaining that these findings remain preliminary and are not predictive of the final Phase 3 results.

The significance of this announcement lies in the potential of GLSI-100 to address a substantial unmet medical need in breast cancer recurrence prevention. The expanded study design and regulatory support indicate increased confidence in the trial's approach. For further details, the full press release is available at https://ibn.fm/elLnN. More information about Greenwich LifeSciences can be found at www.greenwichlifesciences.com.

The FLAMINGO-01 trial evaluates GP2, a 9 amino acid transmembrane peptide of the HER2 protein, which is expressed in 75% of breast cancers at low, intermediate, and high levels. If successful, GLSI-100 could offer a new therapeutic option for patients who have undergone surgery. The company is a clinical-stage biopharmaceutical firm focused on preventing breast cancer recurrences.