The Safety and Tolerability of PGV001-based Personalized Multi-peptide Vaccines in the Adjuvant Setting.

This proof of concept study is designed to test the safety and tolerability of PGV001-based personalized multi-peptide vaccines in combination with CDX-301 in subjects with a history of aggressive prostate cancer, in the tumor free adjuvant setting. This study will also assess the capacity of PGV001-based a multi-peptide therapeutic vaccines to produce a robust tumor antigen-specific T lymphocytic response in the peripheral circulation when combined with CDX-301, and it will expand the collective body of knowledge regarding the identification, selection and use of mutation-derived tumor antigens for personalized immunotherapy in prostate cancer patients. The purpose of the proposed trial will be to assess the following hypothesis: Mutation-derived tumor antigens (MTA) may arise as a result of somatic non-synonymous variations-including nucleotide substitutions, as well as small insertions and deletions-which occur during tumorigenesis. Somatic mutations may be characterized through the use of high-throughput sequencing technologies, and the resulting sequence data used to identify TSA. Sequence data can inform the design of patient-specific immune-based therapies, which may be capable of inducing quantitative changes in the concentration of circulating antigen-specific T lymphocytes directed against TSA, which may in-turn lead to immune-mediated elimination of residual malignant cells.