ATLANTA, June 3 /PRNewswire/ -- Bayer HealthCare, a member of the Bayer Group , today announced findings from a study using Bayer Diagnostics' Serum HER-2/neu Test that demonstrated metastatic breast cancer (MBC) patients whose serum HER-2/neu levels decreased by less than 20 percent experienced decreased benefit from trastuzumab-based therapy. The data, from a pooled analysis of seven clinical trials in the United States and Western Europe of MBC patients who received trastuzumab (with or without chemotherapy), were presented today at the annual meeting of the American Society of Clinical Oncology (ASCO) in Atlanta, GA by Suhail Ali, M.D., Associate Professor, Division of Hematology Oncology, Penn State College of Medicine, the Penn State Milton S. Hershey Medical Center. The Serum HER-2/neu Test from Bayer Diagnostics is the only blood test cleared by the U.S. Food and Drug Administration for ongoing monitoring of changes in serum levels of HER-2/neu. HER-2/neu is a protein that helps control cell growth.
The findings allowed the 307 MBC patients who had the Serum HER-2/neu Test before and after trastuzumab-based treatment to be divided into those with a greater than 20 percent decrease in serum HER-2 /neu levels and those with a less than 20 percent decrease. The patients whose serum HER-2/neu levels decreased by less than 20 percent had a lower response rate; shorter duration of response; shorter time to progression; and decreased overall survival rate.
"In this analysis, measuring serum HER-2/neu levels provided an early predictor of the outcome of trastuzumab-based therapy in MBC patients. For instance, patients with < 20% decrease in serum HER-2/neu have a decreased disease free and overall survival with trastuzumab based therapies. Patients with < 20% should be considered for investigative agents in addition to trastuzumab. The Serum HER-2/neu Test represents a model for the future of personalized medicine in which a serum biomarker is used to direct therapy at an individual level," said Allan Lipton, M.D., Professor of Medicine and Oncology, Penn State College of Medicine, the Penn State Milton S. Hershey Medical Center and a co-author of the pooled analysis.
The standard method for determining HER-2/neu status is by testing tissue from the primary tumor, usually involving an invasive procedure. A simple blood test to determine serum HER-2/neu levels during the course of therapy is complementary to tissue testing because continuous monitoring of serum concentrations of HER-2/neu allows physicians to follow disease progression and therapy response, thereby guiding on-going treatment decisions. The Serum HER-2/neu Test is the only test that can track a woman's HER-2/neu level once she is diagnosed with MBC regardless of whether the treatment is hormone therapy, chemotherapy or trastuzumab-based therapy because it is a serum biomarker for HER-2/neu positive tumors.
"We are moving toward a new paradigm in the monitoring and management of breast cancer patients," said Dr. Ali. "There are patients on trastuzumab who are achieving great results from the therapy and some who are not receiving the maximum benefit. It is important for doctors to know about the latter group as early as possible so they can optimize treatment regimens."
The most prevalent cancer in the world is breast cancer, with approximately 4.4 million survivors up to five years following diagnosis.(i) In the United States alone, more than 200,000 women are diagnosed with breast cancer annually.(ii) Approximately 30-50 percent of these women are identified as having too much HER-2/neu, and may be candidates for HER-2/neu targeted therapy.(iii)
About the Study
The study included a pooled analysis of seven trials of first-line trastuzumab therapy (with or without chemotherapy) in MBC patients. A pretreatment and post-treatment (16-120 days) serum test was conducted on 307 patients. Patients whose serum HER-2/neu levels decreased by less than 20 percent had a lower response rate (28.4 percent vs. 56.5 percent, p<0.001); shorter duration of response (230 days vs. 369 days, p=0.008); shorter time to progression (182 days vs. 320 days, p<0.001); and decreased overall survival rate (593 days or 1.6 years vs. 898 days or 2.5 years, p=0.018).
About HER-2/neu
HER-2/neu, or Human Epidermal Growth Factor Receptor 2, is a protein that helps control cell growth. A cell with too many copies of the gene that codes for HER-2/neu may lead to excess production of the HER-2/neu oncoprotein, which plays a role in turning a normal cell into a cancer cell. In MBC patients, the portion of the HER-2/neu protein that is outside of the cell, the extracellular domain or ECD, is cleaved and released into the bloodstream while the remaining receptor is activated and promotes tumor cell growth. HER- 2/neu-targeted therapies such as trastuzumab inhibit cleavage of the HER-2/neu ECD. Rising serum HER-2/neu concentrations, as measured by the Serum HER-2/neu Test, are therefore associated with progressive metastatic disease and poor response to HER-2/neu targeted therapies and conventional hormone and chemotherapies.
About the Serum HER-2/neu Test
The Serum HER-2/neu Test is intended for in vitro diagnostic use in the quantitative determination of the HER-2/neu protein in human serum. HER-2/neu values obtained may be used in the follow-up and monitoring of patients with MBC whose initial serum HER-2/neu level is greater than 15 ng/mL. HER-2/neu values should be used in conjunction with information available from clinical and other diagnostic procedures in the management of breast cancer.
Recent clinical studies have also shown that up to 40 percent of breast cancer patients who had HER-2/neu negative tumors at first diagnosis later became HER-2/neu positive.(iv) The Serum HER-2/neu Test allows physicians to identify patients whose original tissue biopsies were HER-2/neu negative, not tested, not available for testing, or were stored for a long period of time, but who subsequently become positive after their cancers have spread.
This test should be used by or under the order of a physician. This assay can be performed on the ADVIA Centaur Immunoassay System or via the ELISA microtitre plate. It is not intended for use on any other system.
The clinical utility of measurement of HER-2/neu in serum as a prognostic indicator for early recurrence and in the management of patients on immunotherapy has not been fully established.
About Oncogene Science
Bayer Diagnostics' Oncogene Science Group (http://www.oncogene.com/) functions as a specialized center of excellence focused on clinical research and development of cancer diagnostic tests based on oncogenes, tumor suppressor genes and other gene targets whose proteins are directly involved in tumor growth or metastasis. These tests are designed to aid oncologists in the confirmation, monitoring, staging, screening or prognosis of human cancer. Bayer Diagnostic's Oncogene Science provides a pipeline of biomarker tests that may be used with specific cancer therapies, thus linking diagnostics with therapies through the development of biomarkers.
About Bayer HealthCare, Diagnostics Division
Bayer HealthCare Diagnostics Division is one of the world's market leaders in diagnostics for critical and intensive care, hematology, DCA (hemoglobin A1C), urinalysis, immunochemistry, clinical chemistry and molecular testing. With operations in more than 100 countries, Bayer Diagnostics offers an extensive portfolio of diagnostic systems, point of care testing, molecular diagnostics, laboratory automation and productivity solutions and services to hospitals and health care organizations, laboratories and physicians' offices across the world.
Bayer Diagnostics' extensive portfolio covers a myriad of congenital and acquired disease states, including: allergy, anemia, autoimmune disorders, cardiopulmonary care, cardiovascular/heart, diabetes, fertility, infectious diseases, HIV/AIDS, urinary tract infections, kidney and metabolic function, thyroid functions, oncology and virology, as well as immunosuppressant therapy and therapeutic drug monitoring.
Bayer HealthCare Diagnostics Division global headquarters is based in Tarrytown, New York, U.S.A, and operates as part of Bayer HealthCare LLC.
About Bayer HealthCare AG
Bayer HealthCare AG, a subsidiary of Bayer AG, is one of the world's leading, innovative companies in the health care and medical products industry. In 2004, the Bayer HealthCare subgroup generated sales amounting to some 8.5 billion Euro. Bayer HealthCare employed 35,300 people worldwide in 2004.
The company combines the global activities of the divisions Animal Health, Consumer Care, Diabetes Care, Diagnostics and Pharmaceuticals. Since January 1, 2006 the new Pharmaceutical Division consists of the former Biological Products and Pharmaceutical Division and now comprises three business units: Hematology/Cardiology, Oncology and Primary Care.
Bayer HealthCare's aim is to discover and manufacture innovative products that will improve human and animal health worldwide. The products enhance well-being and quality of life by diagnosing, preventing and treating disease.
DAKO A/S (http://www.dako.com/) is the worldwide distributor of the Serum HER-2/neu Test. Oncogene Science and Bayer HealthCare Diagnostics Division manufactures the Serum HER-2/neu Test and provides it on its fully automated ADVIA Centaur(R) Immunoassay System or via the ELISA microtitre plate.
(i) Parkin DM, et al. Global Cancer Statistics, 2002. CA Cancer J Clin 2005; 55:74-108. Abstract available at: http://caonline.amcancersoc.org/cgi/content/abstract/55/2/74?etoc. Accessed May 12, 2006.
(ii) Detailed Guide: Breast Cancer. What are the Key Statistics for Breast Cancer? American Cancer Society Web site. http://www.cancer.org/docroot/CRI/content/CRI_2_4_1X_What_are_the_key_statisti cs_for_breast_cancer_5.asp?sitearea=. Accessed May 15, 2006.
(iii) Schippinger W et al. The course of serum HER-2/neu levels as an independent prognostic factor for survival in metastatic breast cancer. Oncology Reports. June 2004;11(6):1331-6.
(iv) Carney, WP. Personalized Medicine 2005;2(4):317-324.
