Folate Receptor Alpha Peptide Vaccine With GM-CSF in Patients With Triple Negative Breast Cancer

Triple negative breast cancers (TNBCs) occur in approximately 20-25% of all patients with breast cancer and are associated with a poor prognosis. Patients with TNBCs derive no benefit from targeted therapies. Excluding those patients who demonstrate a pathologic complete response following neoadjuvant chemotherapy, which is a minor fraction (i.e. 15%), overall survival is only 45% at 7 years. Following standard of care, there are windows of opportunity to further and safely treat patients to prevent recurrence. Stimulating the immune system to produce T cells immunity specific for tumor antigens may significantly delay recurrence and cure patients. The proposed vaccine is intended to induce T cells to survey for the reemergence of TNBCs and to prevent recurrence in the adjuvant setting. The vaccine strategy is antigen-specific and targets the Folate Receptor Alpha (FRα). FRα is an ideal target because of its limited expression in the healthy tissues and it high expression in 86% of TNBCs. Studies have shown that it is a biologically important marker that is associated with poorer clinical outcome and is retained in metastatic lesions. The FRα vaccine include a pool of 5 peptides that are immunogenic epitopes and safely generate tissue-surveying CD4 T cell immune responses in patients tested in a recently completed phase I clinical trial.