Safety and Efficacy of Herceptin + Chemotherapy Further Supported by Studies Presented at Breast Cancer Conference

SAN ANTONIO (PROTEXT) - New advances in the study of Herceptin(R) (trastuzumab), when used in combination with common chemotherapies for the treatment of advanced (metastatic) breast cancer, were highlighted in two presentations at the 22nd Annual San Antonio Breast Cancer Symposium. Herceptin Plus Vinorelbine Combination Study Reports Encouraging Results In a study led by investigators at Dana-Farber Cancer Institute, Herceptin and the chemotherapy agent vinorelbine have been used to treat 34 women with HER2-positive, advanced breast cancer. Most women in this study had previously received chemotherapy treatments for their breast cancer. "The response rate to date of over 70 percent is encouraging, particularly when considering that these women with breast cancer have the more aggressive HER2-positive form of the disease," said Dr. Harold J. Burstein, a lead investigator on the study at Dana- Farber. "A gratifying aspect of the study is that the treatments have, so far, been very well tolerated with relatively few side effects." Dr. Eric P. Winer, head of breast oncology at Dana-Farber and senior investigator for the study, stated that, "while the data presented today are encouraging, they are still preliminary. We are continuing to care for women on this study, and are cautiously optimistic that this will prove a valuable regimen for treating advanced breast cancer." Herceptin and Weekly Taxol Therapy Appears to Show Higher Response Rates in HER2-Positive Patients In a separate study, preliminary analysis showed that among the 62 evaluable patients, Herceptin and weekly Taxol combination therapy increases response rates in HER2-overexpressing metastatic breast cancer patients compared to non-HER2 overexpressing patients. Francisco J. Esteva, M.D., assistant professor of medicine at The University of Texas M. D. Anderson Cancer Center reported that these preliminary results of HER2- positive patients receiving weekly doses of Herceptin plus Taxol had a 78 percent response rate compared to a 50 percent response rate in non-HER2 overexpressing patients. The highest response rates were noted in patients whose tumours were HER2 positive by a combination of monoclonal and polyclonal antibodies. Fluorescence in situ hybridization was also a good predictor for response to weekly Taxol plus Herceptin. "This study highlights the importance of optimizing HER2 testing methodology as a predictor for response to Herceptin- based therapy," said Dr. Esteva. Future trials are currently being planned to further investigate the use of Herceptin and weekly Taxol in HER2-overexpressing and HER2 non-overexpressing patients. HER2 and Breast Cancer HER2 is a protein produced by a specific gene with cancer- causing potential. This protein serves as a receptor for the growth hormones that circulate in the blood and influence the rate of cell growth and differentiation. Under normal conditions, there are two copies of the gene that produces HER2. Researchers discovered that sometimes this gene is amplified, resulting in more copies than are needed. This amplification, in turn, triggers an overproduction, or overexpression, of the growth- factor receptor HER2. Excess amounts of HER2 lead to the uncontrolled cellular growth that is the hallmark of cancer. Approximately 30 percent of women with breast cancer overexpress HER2. Because HER2 overexpression is related to poor overall prognosis with faster relapse time at all stages of breast cancer development, it is important that patients diagnosed with breast cancer are tested for their HER2 status. Roche Pharmaceuticals Herceptin was discovered and developed by Genentech, Inc., a leading U.S. biotechnology company in which Roche owns a majority share. In July 1998, Genentech granted Roche exclusive marketing rights for Herceptin outside the United States. Roche and Genentech will also work together in a joint global development program for other solid tumours, such as non-small cell lung and colorectal cancers. Roche, headquartered in Basel, Switzerland, is a worldwide leader in research-based healthcare with principal business in pharmaceuticals, diagnostics, vitamins, and fragrances and flavours. Roche discovers, develops and markets prescription drugs in key therapeutic areas such as diseases of the nervous system, virology, infectious diseases, oncology, cardiovascular diseases, inflammatory and autoimmune diseases, dermatology, metabolic disorders and respiratory diseases. ots Original Text Service: Roche Pharmaceuticals Internet: http://www.newsaktuell.de Contact: Kim Callahan, +1-212-453- 2425, callahak@fleishman.com, or Robin Gallon, +44-1235-554627, r.gallon@synapse-uk.com, both of Fleishman-Hillard for Roche Subscribers please note that material bearing the slug "PROTEXT" is not part of CTK's news service and is not to be published under the "CTK" slug. Protext is a commercial service providing distribution of press releases from clients, who are identified in the text of Protext reports and who bear full responsibility for their contents. PROTEXT