New Study Shows Promising Results for Herceptin / Safety and Efficacy Demonstrated in Women With Advanced HER2- Positive Breast Cancer

BASEL, Switzerland (PROTEXT) - Women with advanced (metastatic) breast cancer who were treated with Herceptin(R) (trastuzumab) demonstrated long-lasting, significant response to therapy with almost none of the side effects commonly seen with conventional chemotherapeutic agents, according to a study of 222 women with HER2-positive breast cancer published in the September Journal of Clinical Oncology. "These HER2-positive breast cancer patients had a very poor prognosis and despite aggressive treatment, their cancers had progressed," said Dr. Melody Cobleigh, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois, USA and lead investigator of the study. "Therefore, the response rate and the duration of response seen in this study are significant. Women treated with Herceptin also showed an initial stabilisation in their quality of life. Cancer patients experience a decrease in their quality of life brought on not only by the cancer but also by conventional chemotherapy, and this stabilisation is very important for the emotional well-being of these patients." The study examined 222 women with HER2-positive tumours who received Herceptin monotherapy for cancer that had progressed after at least one prior course of chemotherapy. According to an independent response evaluation committee comprised of radiologists and oncologists, 15 percent of patients responded to Herceptin treatment. Eight women (4 percent) who received Herceptin had a complete response, defined as no evidence of the cancer in their body, and 26 women (11 percent) had a partial response, defined as a decrease in tumour size of at least 50 percent. At six months, 22 percent of patients were free of disease progression. Among the 34 responders, average time-to- treatment failure (TTF), defined as the time from initiation of the study to disease progression, was 11 months. These same patients had an average TTF of only 5.1 months with their prior chemotherapy regimen. Herceptin targets the HER2 receptor (human epidermal growth factor receptor 2), a protein found in excessive amounts on the surface of some breast cancer cells. Approximately 30 percent of women with breast cancer overexpress HER2, and such overexpression of HER2 is associated with a more aggressive form of the disease. However, this study found that higher levels of HER2 expression correlated with a better response to Herceptin. Because Herceptin targets a specific cellular receptor and not all rapidly dividing cells, as do most chemotherapies, Herceptin treatment produces almost none of the commonly observed side effects associated with chemotherapy such as hair loss, nausea, vomiting, and immune system toxicity. "In the majority of cases, patients who have taken this drug have also received chemotherapy, and as far as they are concerned, it's like comparing day and night," said Dr. Martine Piccart, Assistant Professor in the Department of Internal Medicine and Head of the Chemotherapy Department, Jules Bordet Institute, Brussels, Belgium. "With Herceptin, they have a virtually normal life. They are not tired. They are not ill, and consequently the majority, if not all, patients much prefer this treatment to chemotherapy." The most common side effects in this study were mild-to- moderate and included fever, chills, pain, and shortness of breath. These side effects usually did not recur after the first infusion. Twenty-nine of the 222 patients suffered severe side effects, including ten women (less than 5 percent) who had symptoms of cardiac dysfunction. All ten had risk factors for cardiac complications, including anthracycline treatment or pre- existing cardiac disease, and most of the patients improved after standard medical treatment. Overall, only one percent of patients were withdrawn from the study due to side effects. 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 world-wide 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, 212-453-2425, or callahak@fleishman.com, or Melinda Winter, 212-453-2456, winterm@fleishman.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