Phase II calm extension study: Coxsackievirus A21 delivered intratumorally to patients with advanced melanoma induces immune-cell infiltration in the tumor microenvironment

Background CAVATAK, an oncolytic immunotherapy, is a bioselected oncolytic strain of Coxsackievirus A21 (CVA21). Following intratumoral (IT) injection, CVA21 preferentially infects ICAM-1 expressing tumor cells, resulting in viral replication, cell lysis, and a systemic anti-tumor immune response. The Phase II CALM study investigated the efficacy and safety of IT CVA21 in pts with advanced melanoma. The primary endpoint of the study was achieved with 22 of 57 (38.6%) evaluable pts with durable responses observed in both injected and uninjected melanoma metastases, suggesting the generation of significant host anti-tumor responses. Pre-clinical studies in an immune-competent mouse model of melanoma revealed that combinations of intratumoral CAVATAK and antiPD-1 or anti-CTLA-4 mAbs mediated significantly greater anti-tumor activity compared to use of either agent alone. Here we report on a continuation study aimed at understanding the immune mediated effects of CVA21.