PVSRIPO

PVSRIPO, or PVS-RIPO, is the name of a modified polio virus that has recently shown promise for treating cancer. It is the focus of clinical trials being conducted at Duke University.

PVS-RIPO consists of a genetically modified nonpathogenic version of the oral poliovirus Sabin type 1. The internal ribosome entry site (IRES) on the poliovirus was replaced with the IRES from human rhinovirus type 2 (HRV2), to avoid neurovirulence. Once administered, the virus enters and begins replicating within cells that express CD155/Necl5, which is an onco-fetal cell adhesion molecule that is common across solid tumors.

A website at Duke University describes many of properties of PVSRIPO, and historical background about using viruses to oppose cancer. According to that website, "The FDA approved clinical trials with PVS-RIPO in brain tumor patients recently. Since May 2012, five brain tumor patients have been treated. Remarkably, there have been no toxic side effects with PVS-RIPO whatsoever, even at the highest possible dose (10 billion infectious virus particles)."

The potential value of PVSRIPO was the focus of a 2015 story on 60 Minutes.

In May 2016, the US Food and Drug Administration granted it breakthrough therapy designation for glioblastoma.