FDA Lifts Clinical Hold on Phase 3 Trial Assessing GLSI-100 in Patients With HER2/Neu-Positive Breast Cancer and HLA-A*02

The phase 3 FLAMINGO-01 trial (NCT05232916) assessing the safety and efficacy pf GLSI-100 in HER2/Neu-positive breast cancer in patients who are HLA-A*02 positive has been given FDA clearance to resume after the organization lifted a clinical hold, according to a press release from Greenwich LifeSciences.

The hold was previously placed on the trial by the FDA following concerns pertaining to manufacturing and pharmacy processes. The FDA indicated that the concerns had been adequately addressed following discourse with Greenwich LifeSciences and testing of the agent in the pharmacy process. The FLAMINGO-01 trial has been given the go-head to resume as previously planned and site visits have begun.

GLSI-100 is an immunotherapeutic agent created for the treatment of HLA-A*02-positive patients with HER2/neu-positive disease at high risk of recurrence following completion of neoadjuvant and adjuvant standard of care therapy.

The trial has an estimated enrollment of 598 patients. Treatment with GLSI-100 consists of 500 mcg/mL of the HER2/Neu peptide GP2 and 125 mcg/mL granulocyte-macrophage colony-stimulating factor (GM-CSF) administered intradermally once monthly for the first 6 months followed by every 6 months for the subsequent 2.5 years, or placebo.

The trial has a primary end point of invasive breast cancer–free survival, with secondary end points including invasive disease–free survival, distant disease–free survival, overall survival, and quality of life. The trial will also assess immune response measurements.

Patients were required to be HLA-A*02 positive with histologically confirmed HER or neu positivity with stage I, II, or III disease at presentation. Patients could not enroll with clinical evidence of residual or persistent breast cancer. Additional inclusion criteria were an ECOG performance status of 0 to 2, adequate organ function, a negative pregnancy test, and a willingness to use a highly effective contraceptive, if applicable.

Patients with stage IV, metastatic disease, or inflammatory disease were not eligible for enrollment. Moreover, patients who were receiving other investigational agents, chemotherapy, or who required systemic treatment with corticosteroids or other immunosuppressive therapies were not eligible. Other exclusion criteria included a history of immunodeficiency or active autoimmune disease, a history of serious allergic reactions to GM-CSF, or active infection. Patients with known human immunodeficiency virus viral load within 6 months of starting treatment and those with other malignancies with the exception of properly treated in situ cervical carcinoma or basal or squamous cell carcinoma of the skin were not able to enroll on the FLAMINGO-01 trial.

Reference

Greenwich LifeSciences announces removal of clinical hold permitting phase III clinical trial to proceed. News release. Greenwich LifeSciences. July 12, 2022. Accessed July 14, 2022. https://bit.ly/3Pn5zFG