Cell Genesys, Inc. has commenced a Phase 1 clinical trial of CG0070, an oncolytic virus therapy with specificity for multiple cancers, which will be initially evaluated in patients with recurrent bladder cancer.

CG0070 is the first "armed" oncolytic virus therapy developed by the company, so-named because it has been engineered to include the therapeutic gene for GM-CSF, an immune stimulating hormone which also serves as the adjuvant in Cell Genesys' GVAX cancer vaccine platform.

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.

Joseph J. Vallner, president and chief operating officer of Cell Genesys said, "We are optimistic that the dual mechanism of action of CG0070 might result in enhanced local anti-tumour activity as well as systemic anti-tumour immunity following local administration."

This open-label, dose-escalation trial is designed to evaluate intravesical (into the bladder) administration of CG0070 in patients with bladder cancer who have failed previous therapy with bacillus Calmette-Guerin (BCG), the current standard therapy for recurrent bladder cancer. The trial is expected to enrol up to approximately 36 patients and will be conducted at up to 10 medical centres in the United States. 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.

In 2003, Cell Genesys entered into a global alliance with Novartis AG for the development and commercialization of certain oncolytic virus therapy products. The alliance provided Cell Genesys with preclinical stage product opportunities developed by Novartis, including CG0070.