Know Cancer

forgot password

Phase 3
18 Years
Not Enrolling
Breast Neoplasms, Neoplasms, Hormone-Dependent

Thank you

Trial Information

Breast cancer cells are often very dependent on estrogens to continue to grow. Atamestane
blocks the formation of estrogens and androgenic precursors in the body. Toremifene blocks
circulating and intracellular estrogens from stimulating estrogen receptors in breast cancer
cells. The goal of therapy with atamestane, an aromatase inhibitor, in combination with the
estrogen receptor antagonist, toremifene, is to achieve maximal suppression of estrogen
stimulation of breast cancer cells. This study is designed to determine whether combination
therapy will lengthen the time to disease progression and the rate of objective response
compared to single agent aromatase inhibitor therapy with letrozole.

Inclusion Criteria:

- Women age 18 years or older

- Pathological or histological confirmation of breast cancer at initial diagnosis or at
the time of metastases

- ECOG performance status of 0, 1 or 2 or Karnofsky performance status of 60 or higher

- Predicted life expectancy of 12 weeks or more

- Postmenopausal endocrine status. LH/FSH levels in the postmenopausal range in women
whose menopause occurred less than 5 years ago

- Locally recurrent, locally advanced, locally metastatic disease not amenable to
radiation therapy or surgery and/or distant metastatic disease

- At least one tumor localization measurable in 2 dimensions (one diameter at least 2
cm for soft tissue/visceral disease assessed by CT/MRI scan or conventional X-ray
technique, one diameter at least 1 cm for bone lesions assessed by conventional X-ray

- Estrogen receptor and/or progesterone receptor positive (by laboratory/institutional
standard) at the time of initial diagnosis or determined during subsequent
biopsy/surgery of metastases

- Written informed consent obtained

Exclusion Criteria:

- Prior hormonal therapy to treat locally recurrent, locally advanced or metastatic

- Prior adjuvant therapy with aromatase inhibitors or antiestrogens/SERMs within 12
months prior to enrollment

- Progression of disease during therapy with antiestrogens (including SERMs
administered for prevention of osteoporosis)

- Life-threatening locally recurrent, locally advanced or metastatic disease or disease
requiring chemotherapeutic intervention (such as inflammatory breast cancer)

- History of known CNS metastases, significant neurological dysfunction including
active seizures, or clinical signs of other significant neurological diseases

- Other active malignancy (except basal cell carcinoma of the skin or in situ cervical
cancer). Patients with previous malignancies must be without evidence of disease for
at least five years

- Renal insufficiency (serum creatinine > 2.0 mg/dL)

- Aspartate aminotransferase, alanine aminotransferase or serum bilirubin levels more
than 2.5 times upper limit of normal

- Hemoglobin <9 g/dL

- Platelet count of less than 100,000 platelets per mm3

- Total white blood cell count of less than 2,000 cells per mm3

- Premenopausal endocrine status; pregnant or lactating females

- Usage of an investigational drug within the thirty (30) days prior to enrollment; or
the planned usage of an investigational drug other than the study medication during
the course of the current study

- Contraindication to use of toremifene, atamestane, letrozole or any of the inactive
components of their formulations

- Prior enrollment in this study

Type of Study:


Study Design:

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Principal Investigator

Paul Goss, M.D.

Investigator Role:

Study Chair

Investigator Affiliation:

Princess Margaret Hospital, Canada


United States: Food and Drug Administration

Study ID:

Biomed 777-CLP-29



Start Date:

June 2002

Completion Date:

January 2006

Related Keywords:

  • Breast Neoplasms
  • Neoplasms, Hormone-Dependent
  • Atamestane
  • Toremifene
  • Letrozole
  • Aromatase inhibitor
  • Receptor-positive
  • First line therapy
  • Estrogen blocker
  • Metastatic breast cancer
  • Locally advanced breast cancer
  • Locally recurrent breast cancer
  • stage IV breast cancer
  • ductal breast carcinoma
  • lobular breast carcinoma
  • stage IIIA breast cancer
  • stage IIIB breast cancer
  • recurrent breast cancer
  • Breast Neoplasms
  • Neoplasms
  • Neoplasms, Hormone-Dependent



California Cancer Care, Inc. Greenbrae, California  94904-2007
Virginia Oncology Associates Newport News, Virginia  23606
Georgia Cancer Specialists Decatur, Georgia  30033
Oncology Consultants Houston, Texas  77024
Sharp Memorial Hospital San Diego, California  92123
Arizona Clinical Research Center Tucson, Arizona  85712
Oncology Care Associates, PLLC Saint Joseph, Michigan  49085
Maryland Hematology/Oncology Associates Baltimore, Maryland  21236
Kansas City Oncology and Hematology Group Kansas City, Missouri  64111
Midwest Internal Medicine, PLLC Lake Havasu City, Arizona  86403
Innovative Medical Research of South Florida Inc. Miami Shores, Florida  33138
Great Falls Clinic-Oncology West Great Falls, Montana  59405
Slocum-Dickson Medical Group New Hartford, New York  13413
Hematology Oncology Consultants, Inc. Columbus, Ohio  43235
First Dynamic Healthcare Services, Inc. Killeen, Texas  76710
Cache Valley Cancer Treatment & Research Clinic Logan, Utah  84341
Western Washington Oncology Inc., P.S. Olympia, Washington  98502