Greenwich LifeSciences, Inc. (Nasdaq: GLSI) announced that the European Medicines Agency (EMA) has completed its review and will allow the combination of both HLA-A*02 and non-HLA-A*02 patients in the FLAMINGO-01 Phase III clinical trial in Europe.

The decision aligns European sites with a protocol already in place at U.S. sites, where the Food and Drug Administration previously reviewed and allowed the same change. All 170 to 180 clinical sites across the U.S. and Europe are now operating under the same protocol. The company said data can also be analyzed by individual HLA types.

Non-HLA-A*02 patients represent approximately 55% of the general population and had previously been placed on waiting lists for up to a year. The company said combining the two patient groups more than doubles the enrollment rate of the pivotal arm of the study.

Greenwich LifeSciences also reported preliminary open-label data from the 250-patient non-HLA-A*02 arm, which is now fully enrolled. A preliminary analysis of recurrence rates after the Primary Immunization Series showed an approximately 70% to 80% reduction in recurrence rate. The company noted this observation is trending similarly to results from its earlier Phase IIb trial.

The company said the immune response and safety profile in non-HLA-A*02 patients is trending similarly to the HLA-A*02 arms of FLAMINGO-01 and to the Phase IIb study. Greenwich LifeSciences cautioned that the open-label data is preliminary, not fully reviewed, and is not a prediction of final study results.

Additional regulatory feedback is expected from UK and Canadian regulators. The company said the combined analysis of both patient groups could potentially double the market for its GP2 immunotherapy candidate, GLSI-100, which is being evaluated for the prevention of breast cancer recurrences in HER2-positive patients. The trial is led by Baylor College of Medicine.

More than 1,300 patients have been screened in FLAMINGO-01, with a current screening rate of approximately 800 patients per year, according to the company's statement.