Onyx Awarded Patent For Viral Cancer Therapy.
The patent specifically covers the use of modified adenoviruses and other DNA viruses, which lack viral proteins that bind to the tumor suppressor protein p53, to treat cancer patients whose tumors lack p53 function.
"The idea of treating cancer with a modified adenovirus originated here at Onyx with our founder Dr. Frank McCormick," said Hollings Renton, president and chief executive officer of Onyx. "As a company we have pursued the concept through research, development, preclinical studies and into human clinical trials. This patent provides protection for our leading position as developer of this novel approach to cancer therapy."
Dr. McCormick is the sole inventor listed on the patent. He founded Onyx in 1992, and currently serves on the company's scientific advisory board.
The role of the p53 tumor suppressor gene is to prevent replication of abnormal DNA during the process of cell division. In normal cells, p53 detects errors in DNA and either halts the cycle of cell division until the errors are corrected, or forces the cell to undergo apoptosis or "cell suicide." If p53 has mutated and become inactive, the cell's DNA continues to replicate even if it contains many errors. As a result abnormal cells can survive and multiply.
Mutations in the p53 tumor suppressor gene are the most common genetic abnormalities found in human cancers, appearing in more than half of all cancers. One of the functions of this gene is to shut down the cell's reproductive machinery upon viral invasion. Viruses, however, can overcome this defense by producing special viral proteins that disable this regulating gene.
The viruses developed by Onyx are genetically modified such that they do not produce the proteins responsible for inactivating p53. As a result, these modified viruses do not replicate effectively in normal cells, but do replicate in and kill p53-deficient tumor cells. Preclinical studies of ONYX-015, which targets tumor cells that are either p53-deficient or that have non-functioning p53, have shown that once these mutated cancer cells are infected with the modified adenovirus, the virus growth cycle continues to proceed unchecked and the cancer cells burst and die.
In June 1997, Onyx completed enrollment in its first Phase I study of the ONYX-015 adenovirus in patients with recurrent and refractory cancer of the head and neck. The company is currently conducting Phase II trials in the same patient population. Onyx recently announced initiation of a second Phase II study treating head and neck cancer patients with ONYX-015 in combination with chemotherapy. In addition, Phase I trials are underway in pancreatic cancer, ovarian cancer, and in gastrointestinal cancers that have metastasized to the liver.
Onyx Pharmaceuticals was founded in 1992 for the purpose of discovering and developing novel therapeutics based upon the genetics of human disease, with an emphasis on cancer. The company focuses on defining the function of certain mutated genes which are known to cause cancer, and on developing innovative therapies to reverse the effects of the mutation or to kill the cancer cell. Onyx pursues a strategy of establishing corporate partnerships that provide complementary skills in chemistry, drug development, and marketing and sales.
This press release contains certain forward-looking statements with regard to the development of potential human therapeutic products that involve a number of risks and uncertainties. Actual events may differ from the company's expectations. In addition to the matters described in this press release, the timeline for clinical activity, results of pending or future clinical trials, and changes in the status of the company's collaborative relationships, as well as the risk factors listed from time to time in the company's periodic reports filed with the Securities and Exchange Commission, including but not limited to its Annual Report on Form 10-K, may affect the actual results achieved by the company.
CONTACT: Onyx Pharmaceuticals Inc.
Jana R. Cuiper, 510/262-8734
J. Kureczka Associates
Joan Kureczka, 415/821-2413