Systemic efficacy with oncolytic virus therapeutics: clinical proof-of-concept and future directions.

Oncolytic viruses that can destroy cancer cells have been engineered in a variety of ways with the aim of improving their selectivity and efficacy. Here, we review data from clinical investigations of these virotherapeutic agents, specifically those that have shown systemic efficacy: vaccinia, measles, mumps, viruses, Newcastle disease virus, and reovirus. Further directions for optimizing i.v. delivery and efficacy are discussed.