Phase Ib Trial of Two Folate Binding Protein Peptide Vaccines (E39 and J65) in Breast and Ovarian Cancer Patients

Overview

This is a single-center, randomized, single-blinded, three-arm phase Ib study of the folate binding protein vaccines E39 and J65. The study target population are patients with breast or ovarian cancer diagnosis who have been treated and are without evidence of disease. Disease-free subjects after standard of care multi-modality therapy will be screened and HLA typed. E39 and J65 are cytotoxic T-lymphocyte-eliciting peptide vaccines that are restricted to HLA-A2+ patients (approximately 50% of the U.S. population).

The study is a prospective, randomized, non-blinded, single-center Phase Ib trial. Patients will be identified that have a diagnosis of breast or ovarian cancer, have completed their standard courses of therapy and are disease-free. They will be properly screened, counseled and consented prior to enrollment. Once enrolled, each patient's blood will be tested for HLA-A2 status (approximately 50% will be HLA-A2+). Additionally, their tumors will be tested for FBP-expression and this information will be tracked for purposes of correlative science. Patients who are HLA-A2+ will be stratified based on cancer diagnosis (breast versus ovarian), then randomized by computer tables to one of three arms for the PVS. Each arm will receive 6 monthly injections of peptide + GM-CSF. Arm A will receive six inoculations with E39 peptide; arm B will receive three inoculations with E39 followed by three with J65; and arm C will receive three inoculations with J65, followed by three of E39. Since J65 has not been previously used in humans, a two week waiting period will be instituted between the first and second patients enrolled in either Arm B or C. Immunologic data will be assessed at 1 month and 6 months (±2 wks) after the PVS, specifically ex vivo immunologic recognition of E39 and J65 will be assessed by clonal expansion using a dextramer assay and the in vivo response will be assessed by Delayed Type Hypersensitivity (DTH). Immunologic recognition of E39 will be the primary endpoint, with recognition of J65 serving as an additional data point. The 6 month post-PVS immunologic data will then be used to assess each patient for significant residual immunity (SRI), defined as ≥2-fold increase in E39-specific CD8+ T-cells from the pre-vaccination level. Patients will then be sorted into two groups: those with SRI and those without. Patients within each group will then be randomized to receive one booster of either J65 or E39. Each patient will return to clinic within 1-2 weeks of their 6mo post-PVS visit to receive their single booster inoculation. This second randomization will result in four groups: 1) patients with SRI receiving E39; 2) patients with SRI receiving J65; 3) patients without SRI receiving E39; 4) patients without SRI receiving J65. Immunologic data will then again be gathered at 1 month (±2 wks) and 6 months (±2 wks) post-booster. This final immunologic data will be analyzed for differences between the four groups. Additionally, toxicity data will be gathered. Patients will be monitored closely for one hour after each inoculation with questioning, serial exams, and vital signs every 15 minutes. Patients will then be asked to return to the vaccine clinic 48-72 hours after each inoculation for questioning regarding any local or systemic toxicity and to examine and measure the local reaction at the vaccination sites. The graded toxicity scale (NCI Common Terminology Criteria for Adverse Events, v4.03) will be utilized to assess local and systemic toxicity. GM-CSF dose reduction may be required if \>10cm of erythema and induration is seen at the injection site after any given inoculation.