US Oncology Taking Part in One of the Largest Clinical Trials for Early Stage Breast Cancer; Specific Patients Sought for Study That May Lead to New Standard of Treatment.

Business Editors & Health/Medical Writers

US Oncology (Nasdaq:USON) is participating in one of the largest global clinical trials designed to study new approaches to the postoperative use of chemotherapy and the molecularly targeted drug Herceptin(R) (trastuzumab), also known as "adjuvant" therapy, for women with early stage breast cancer.

US Oncology is one of the selected research groups and institutions on five continents taking part in the landmark study, which has been initiated by a worldwide academic cooperative group of clinical investigators -- the Breast Cancer International Research Group (BCIRG). The study is headquartered at the Jonsson Cancer Center at the University of California, Los Angeles (UCLA).

Known as BCIRG-006, the study will focus on a particular type of aggressive breast cancer in which a gene called HER2-neu is altered. The gene is normally involved in regulating cell growth and cell death. Amplification of the HER2-neu gene is linked to rapid cancer growth and decreased patient survival and is found in approximately 20 to 25 percent of malignant breast tumors.

A recent study published in The New England Journal of Medicine stated that Herceptin plus chemotherapy extended survival for women with advanced breast cancer by 24 percent. Researchers now want to determine if the drug will work even better in patients with newly diagnosed breast cancer.

"This international, cutting-edge study is based on the most current scientific findings in breast cancer treatment," said Dr. Nicolas Robert, co-chair of the US Oncology Clinical Research Breast Committee and US Oncology principal investigator for the BCIRG study. "If this approach is shown to be successful, it may lead to a completely new treatment standard for breast cancer patients who are HER2 positive."

Patient enrollment for the trial is now under way within the US Oncology research network. The BCIRG-006 worldwide study will enroll 3,150 patients, who will be randomly assigned to the chemotherapeutic agent Taxotere(R) (docetaxel) in combination with one of three different regimens. Patients will receive one of the following treatments:

-- Adriamycin(R) (doxorubicin) and Cytoxan(R) (cyclophosphamide), known as AC and considered to be one of the current standard adjuvant chemotherapy regimens, followed by Taxotere

-- AC followed by Taxotere with Herceptin

-- Taxotere, Carboplatin and Herceptin

The objective of the study is to determine which of the three treatment regimens is the most effective in keeping patients free of disease and prolonging their survival.

The drugs being tested are currently being used to treat other stages of breast cancer and have been carefully chosen for this study. Taxotere is a widely used agent for the treatment of breast cancer that has been shown to increase survival in advanced disease. It also is the only drug to date that has shown superior efficacy to Adriamycin in a direct comparison.

Herceptin is a monoclonal antibody that has been shown in clinical trials to prolong the survival of patients receiving chemotherapy for metastatic breast cancer, which has the HER2-neu alteration.

A pilot study conducted at UCLA's Jonsson Cancer Center showed this combination to be a safe and effective treatment for advanced breast cancer with the HER2 alteration.

Aventis Pharmaceuticals, the major sponsor of the BCIRG trials, provides funding and Taxotere free of charge for all patients. Genentech Inc. provides funding and Herceptin for patients enrolled in the United States. The testing for HER-2 status will be done with the PathVysion(TM) HER-2 assay, provided by Vysis Inc.

About Breast Cancer

Breast cancer is an abnormal cell growth originating in breast tissue. If not diagnosed and treated early, these cells can invade surrounding tissue and spread through the blood and lymph node system.

More than 780,000 new cases of breast cancer are reported worldwide annually. In the United States, it is the most common cancer among women, excluding skin cancer, and the second leading cause of cancer death among women. The American Cancer Society estimates that 182,800 new cases of invasive breast cancer will be diagnosed among women this year, and more than 40,000 women will die from the disease.

Adjuvant Treatment of Breast Cancer

Adjuvant therapy is the use of medicines, such as chemotherapy or biological drugs, after a tumor has been surgically removed. Adjuvant therapy aims to eradicate any remaining tumor cells that may be too small to be seen, but that might cause a recurrence of disease.

The interest in adjuvant therapy in breast cancer is high, both in women whose disease has spread to the lymph glands under the armpit or have worrisome features such as HER2 positive cancer and a probability of cancer resurfacing in other parts of the body within a decade after surgery.

About BCIRG

BCIRG is the first academic global cooperative intergroup of oncology researchers dedicated to the global strategic development of promising new therapies for breast cancer. The goal of BCIRG is to identify and select the best compounds in their class (chemotherapy, hormone therapy, biological modifiers and gene therapy) and to create global pivotal strategies of development in order to test these new treatments and bring them to patients in a timely manner. BCIRG is a division of the Cancer International Research Group, a not-for-profit organization.

About US Oncology

US Oncology, headquartered in Houston, is America's premier cancer-care services company. The company supports the cancer-care community by providing oncology pharmaceutical services, cancer center services and cancer research services to community-based practices. US Oncology is affiliated with more than 860 physicians operating in over 450 locations, including 77 outpatient cancer centers, in 28 states.

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