Onyx Receives Patent For Replicating Viral-Based Therapy

The U.S. Patent and Trademark Office has granted U.S. patent number 5,801,029 to Onyx Pharmaceuticals Inc., covering methods for treating cancer using replicating viral-based therapy. Dr. Frank McCormick, Onyx's founder in 1992, is the sole inventor listed on the patent.

The patent specifically covers the use of modified adenoviruses and adenoviral compositions, and other DNA viruses lacking viral proteins, that bind to the tumor suppressor protein Rb, to treat cancer patients whose tumors lack Rb function.

The retinoblastoma gene product (pRb) plays a key role in preventing the uncontrolled progression of normal cells from G1 into S phase of the cell cycle until the appropriate proliferation signals are received. pRb function appears to be lost in almost all cancer cells, occurring as a result of Rb deletion or through other mechanisms, thus causing cancer cells to progress continuously through the cell cycle.

Onyx scientists have created a number of novel adenoviruses that are mutated in the regions of the viral genome that interact with Rb. The company has reported encouraging activity with these viruses in preclinical models. Efforts are now underway at Onyx to optimize the anti-tumor efficacy of these novel viruses.

"The Rb program is a natural expansion of our therapeutic virus concept," said Hollings Renton, president and chief executive officer of Onyx. "We are following the same approach in developing the Rb-specific virus as we did in developing the ONYX-015 therapeutic virus, which targets p53-deficient tumor cells."

For more information: Douglas Blankenship, Onyx Pharmaceuticals, Inc., 3031 Research Drive, Richmond, CA 94806. Tel: 510-262-8725. Fax: 510-222-9758.