Pharmaceutical Business review

Genesys begins clinical trial of viral cancer therapy

CG0070 is the first “armed” oncolytic virus therapy developed by Genesys. Extensive preclinical studies have shown that CG0070 can potentially destroy cancer cells by two different mechanisms: direct cell killing by the virus and immune-mediated cell killing stimulated by GM-CSF.

The drug, acquired through an alliance with Novartis AG, is the company’s second oncolytic virus therapy to enter clinical trials. It is hoped the compound will prove affective in promoting local anti-tumor activity and systemic anti-tumor immunity resulting from its duel action when administered to a specific area, in this case the bladder.

The open-label trial will be recruit patients with bladder cancer who have experienced no benefit from previous therapy with bacillus Calmette-Guerin, the current standard therapy for recurrent bladder cancer. The trial is expected to enroll up to approximately 36 patients and will be conducted at up to 10 medical centers in the US. The primary endpoints of the study are safety and the determination of a maximum tolerated dose. Efficacy endpoints include clinical response and recurrence free survival.

Oncolytic (cancer cell killing) virus therapies represent a new approach in the treatment of patients with cancer. This novel therapy utilizes adenoviruses, a cause of the common cold, which are engineered to selectively replicate in targeted cancer cells, thereby killing these cells while leaving healthy normal cells largely unharmed.

The virus is designed to replicate in cancer cells until the cancer cell can no longer contain the virus and bursts. The tumor cell is destroyed and the newly created virus is believed to spread to neighboring cancer cells to continue the cycle of viral replication and tumor cell destruction and may then be cleared by the body’s immune system. Compared with traditional therapies, oncolytic virus therapies may have a higher therapeutic index (greater specificity) with respect to their ability to kill tumor cells.