Greenwich Lifesciences Completed Enrollment In Open-Label HLA-A*02 Arm of FLAMINGO-01 Phase 3 Trial Of GLSI-100, An Immunotherapy To Prevent Breast Cancer Recurrences

In the double-blinded arms of the Phase III trial, approximately 500 HLA-A*02 patients are currently planned to be randomized to GLSI-100 or placebo, and up to 250 patients of other HLA types (non-HLA-A*02) are planned to be treated with GLSI-100 in a third open label arm. The non-HLA-A*02 patients do not have the HLA-A*02 allele from either parent and represent about 55% of the patient population in FLAMINGO-01.

• FLAMINGO-01 has achieved a major milestone by completing enrollment in the 250 patient open label non-HLA-A*02 arm of the Phase III trial, which is a result of the high screen rate and ensuing enrollment rate. The Company is continuing its review of the most recent data of this arm, including recurrence rates, which can be updated and/or published at any time.
• The Company stopped enrolling in this arm earlier this year and is now approaching regulatory agencies to seek approval to continue enrollment of new non-HLA-A*02 patients in a randomized manner with a control arm. The Company has continued to screen a large number of these patients so that rapid enrollment of these screened patients can commence if regulatory approval is received.
• The Company previously reported promising observations earlier this year showing that the immune response at baseline prior to any GLSI-100 treatment, the increasing immune response during the primary immunization series, and the safety profile of non-HLA-A*02 patients is trending similarly to the HLA-A*02 arms of FLAMINGO-01 and to the Phase IIb study, where breast cancer recurrences were reduced up to 80% or more and no metastatic breast cancer recurrences were reported. A preliminary analysis suggests that these promising trends are continuing.