Abstract
A feasibility study was performed to evaluate the immunological efficacy and safety of a personalized peptide vaccine (PPV) for cervical cancer patients who have received platinum-based chemotherapy. A total of 24 patients with standard chemotherapy-resistant cervical cancer, including 18 recurrent cases, were enrolled in this study and received a maximum of 4 peptides based on HLA-A types and IgG levels to the vaccine candidate peptides in pre-vaccination plasma. The parental protein expression of most of the vaccine peptides was confirmed in the cervical cancer tissues. No vaccine-related systemic grade 3 or 4 adverse events were observed in any patients. Due to disease progression, 2 patients failed to complete the first cycle of vaccinations (sixth vaccination). Cytotoxic T-lymphocyte (CTL) or IgG responses specific for the peptides used for vaccination were augmented in half of cases after the first cycle. The median overall survival was 8.3 months. The clinical responses of the evaluable 18 cases consisted of 1 case with a partial response and 17 cases with disease progression; the remaining 6 cases were not evaluable. Performance status, injection site skin reaction and circulating PD-1(+) CD4(+) T-cells were significantly prognostic of overall survival, and multivariate analysis also indicated that the performance status and circulating PD-1(+) CD4(+) T-cells were prognostic. Because of the safety and immunological efficacy of PPV and the possible prolongation of overall survival, further clinical trials of PPV at a larger scale in advanced or recurrent cervical cancer patients who have received prior platinum-based chemotherapy are recommended.