The efficacy of cancer immunotherapy approaches can be significantly hampered by the tumor immune suppressive microenvironment. In the present study, a novel combinatorial strategy (i.e. metronomic chemotherapy plus vaccine) is evaluated in a mouse model in an aggressive therapeutic setting based on sub-cutaneous ectopic implantation of B16 melanoma cells. The chemotherapy is a multi-drug cocktail including taxanes and alkylating agents, administered in a daily metronomic fashion. The vaccine is a multi-peptide cocktail of universal tumor antigen hTERT epitopes adjuvanted in Montanide.

Immunizations have been performed comparing a standard sub-cutaneous delivery with a laser-assisted epidermal immunogen delivery by P.L.E.A.S.E.™ Professional (Pantec Biosolutions). The latter, indeed, creates evenly distributed micropores through to the epidermis and provides a great opportunity to efficiently deliver vaccine antigens to Langerhans cells (LC) in the epidermis.

An interim analysis shows that the immunogenicity as well as the therapeutic effect on tumor growth of the vaccine is significantly increased by the combination with metronomic chemotherapy, and the laser-assisted epidermal immunogen delivery appears to be a very effective strategy as vaccine delivery. Complete description of both immunogenicity and therapeutic effects on tumor growth will be described.

Citation Format: Maria Tagliamonte, Annacarmen Petrizzo, Maria Lina Tornesello, Antonio Luciano, Domenica Rea, Antonio Barbieri, Claudio Arra, Maria Napolitano, Gennaro Ciliberto, Luigi Aurisicchio, Claudio Coscia, Tobias Baechle, Franco M. Buonaguro, Luigi Buonaguro. Evaluation of novel metronomic chemotherapy and cancer vaccine combinatorial strategy. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr B130.