Cell Genesys Granted Exclusive Rights to LentiVirus Patent

Cell Genesys Inc. (Foster City CA) announced that The Salk Institute (La Jolla, CA) has been issued a fundamental patent for lentiviral gene therapy technology (U.S. Patent No. 6,013,516) to which Cell Genesys is the exclusive worldwide licensee. Lentiviral vectors have demonstrated efficient and long-lasting gene transfer into a variety of human cells including non-dividing cells such as nerve, liver, muscle, and bone marrow stem cells. In addition, lentiviral vectors have a larger gene delivery capacity than other gene therapy vectors and can therefore be used to deliver a wider range of therapeutic genes.

The patent for lentiviral gene therapy includes composition of matter claims and methods of production claims for lentiviral gene delivery systems of both human and non-human origin. Cell Genesys is currently pursuing preclinical studies with lentiviral vectors for the treatment of hemophilia.

Cell Genesys currently has four different viral vector systems and is using this technology "toolbox" to capture multiple product opportunities. Viral vectors have demonstrated the ability to deliver genes to multiple cell types with substantially higher levels of gene expression and efficiency compared with non-viral vectors. The company's proprietary vector technologies include AAV, lentiviral, adenoviral, and retroviral vectors engineered to provide safe, efficient, long-term gene expression. The selection of a specific vector is based on several factors including the disease indication, safety considerations, and production efficiencies.

"The combination of the levels and duration of gene delivery seen with lentiviral vectors significantly exceeds that reported with non-viral gene delivery systems. Additionally, lentiviral vectors are an extremely effective method of gene delivery in both dividing and non-dividing cells," stated Stephen A. Sherwin, chairman and CEO of Cell Genesys. "The capacity of lentiviral vectors to deliver genes to a variety of cell types enables us to target multiple diseases including hemophilia, cancer and Parkinson's disease."

Cell Genesys currently has more than 220 issued or granted patents and over 335 pending patent applications. The portfolio includes issued or granted patents for multiple gene delivery systems, specific therapeutic genes and gene therapy applications, and multiple genetically modified cell types used in gene therapy independent of the gene delivery system or therapeutic gene. For example, the portfolio currently contains over 90 filings alone pertaining to the two types of gene delivery systems—lentiviral and adeno-associated viral (AAV)—with potential applicability to the treatment of hemophilia and other genetic deficiency diseases.

For more information: Jennifer Cook Williams, Manager, Corporate Communications, Cell Genesys Inc. 342 Lakeside Dr., Foster City, CA 94404. Tel: 650-425-4542. Fax: 650-425-4457.

Edited by Laura DeFrancesco