Combination of intravenously delivered cavatak (coxsackievirus A21) and immune-checkpoint blockade significantly reduces tumor growth and tumor rechallenge

Background Coxsackievirus A21 (CAVATAK) is a bio-selected oncolytic immunotherapy virus. Following intravenous (i.v) administration, CAVATAK can preferentially infect ICAM-1 expressing tumor cell, resulting in tumor cell lysis and generate a potential systemic immunemediated anti-tumor response. A Phase I/II trial of i.v delivered CAVATAK (NCT01227551) in advanced cancer patients displayed signs of anti-tumor activity in some lesions. Blockade of programmed death protein-1 (PD-1) and or CTLA-4 in patients with metastatic melanoma, NSCLC and metastatic Bladder cancer has resulted in substantial tumor responses via a mechanism involving reversal of tumor induced T cell suppression. We hypothesized that combinations of intravenous deliverved CAVATAK and PD-1 or CTLA-4 blockade may enhance anti-tumor responses, potentially leading to improved clinical activity.