Abstract B37: VSV-GP: A vaccine vector and oncolytic virus

Abstract

Abstract Oncolytic viruses have recently shown significant clinical benefits in several cancers. Interestingly, in addition to debulking the tumor by direct oncolysis, they were found to act as a cancer vaccine by setting free tumor antigen in the presence of virus-induced danger signals, which have an adjuvant effect. However, as oncolytic viruses induce neutralizing antibodies that inactivate the virus, oncolytic viruses are not delivered efficiently to cancer tissue upon repeated systemic application. Thus, repeated applications of oncolytic viruses have been restricted to intratumoral injections, which clinically has not been convincingly effective in metastatic disease. We generated the oncolytic virus VSV-GP (Muik et al., Cancer Res, 2014) that is highly potent, lacks toxicity even at high doses (so far tested in mice and rabbits), can be produced at high titers and, above all, does not induce neutralizing antibodies readily. Thus, VSV-GP is unique among the oncolytic viruses in that it can be applied repeatedly without loosing efficacy. VSV-GP is highly effective leading to cure in several cancer mouse models, i.e. malignant glioma, melanoma, prostate cancer and ovarian cancer. In addition to oncolysis, VSV-GP induced a sound anti-tumor immune response and acted synergistically with other cancer immunotherapeutics. Moreover, VSV-GP was shown to be a highly promising vaccine vector and is the only replication competent viral vaccine vector that efficiently boosts the immune response upon repeated application. VSV-GP is thus a highly versatile replication competent viral vector platform for vaccination and cancer therapy. Citation Format: Alexander Muik, Janine Kimpel, Reinhard Tober, Carles Urbiola, Dorothee von Laer. VSV-GP: A vaccine vector and oncolytic virus. [abstract]. In: Proceedings of the AACR Special Conference: Tumor Immunology and Immunotherapy: A New Chapter; December 1-4, 2014; Orlando, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2015;3(10 Suppl):Abstract nr B37.