Personalized peptide vaccines and their relation to other therapies in urological cancer

Immunotherapy is an important therapeutic modality for urological cancers and several immunological agents for their treatment, such as sipuleucel-T and immune checkpoint inhibitors, have been approved by the FDA. Personalized peptide vaccines (PPVs) are an immunotherapy that uses multiple cancer peptides that are selected to complement pre-existing host immunity. Vaccination with an appropriate, individualized selection of peptides, chosen from a list of candidates, induces stronger and more rapid antitumour immunity in comparison with inoculation of conventional peptide vaccines. Phase I and phase II trials have shown that PPVs are safe and effective in urological cancers. Randomized trials in patients with castration-resistant prostate cancer showed that PPVs can significantly improve progression-free survival and overall survival. However, further studies are needed to evaluate the utility of PPVs in other urological cancers, to identify those patients who will derive the greatest benefit from this approach and to optimize the protocols for combination therapies involving PPVs.