Comparison of recurrent and nonrecurrent ovarian and uterine cancer patients undergoing adjuvant folate receptor vaccine therapy.

5559 Background: Folate Receptor Alpha (FRa) (aka Folate Binding protein (FBP)) is an immunogenic protein that is over-expressed in breast, lung, endometrial (EC) and ovarian cancers (OC). In fact, FRa expression in malignant cells is 20-fold higher compared to normal cells. We are conducting a phase 1 clinical trial with E39, an HLA-A2 restricted, FRa peptide + GM-CSF vaccine, administered in the adjuvant setting to prevent recurrences in high-risk EC and OC patients (pts) rendered clinically disease-free after standard-of-care therapy. In this analysis, we compare in vivo immunologic responses (IR) and disease features between vaccinated recurrent (vR) and vaccinated non-recurrent (vNR) pts. Methods: HLA-A2+ pts enrolled into the vaccine group received 6 monthly intradermal inoculations of E39+250 mcg GM-CSF during the primary vaccine series (PVS). In vivo IR was assessed by both local reaction (LR) after each inoculation (R1-R5) and delayed hypersensitivity (DTH) reaction measured pre-vaccination (DTH1...