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for females ages 18 years and up (full criteria)
at San Francisco, California and other locations
study started
estimated completion:



RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using drugs such as anastrozole and fulvestrant may fight breast cancer by blocking the use of estrogen. It is not yet known whether anastrozole is more effective with or without fulvestrant in treating breast cancer.

PURPOSE: This randomized phase III trial is studying giving anastrozole together with fulvestrant to see how well it works compared to anastrozole alone as first-line therapy in treating postmenopausal women with metastatic breast cancer.

Official Title

Phase III Randomized Trial of Anastrozole Versus Anastrozole and Fulvestrant as First Line Therapy for Post Menopausal Women With Metastatic Breast Cancer



  • Compare the time to tumor progression in postmenopausal women with metastatic breast cancer treated with anastrozole with or without fulvestrant as first-line therapy.
  • Compare the clinical benefit (complete or partial response, confirmed or unconfirmed, or stable disease ≥ 24 weeks) and overall survival of patients treated with these regimens.
  • Compare adverse events in patients treated with these regimens.
  • Determine the prognostic significance of estrogen receptor positivity and HER2/neu status in patients treated with these regimens.
  • Determine parameters of estrogen and clinical pharmacology and estrogen levels in patients treated with these regimens.
  • Compare anastrozole plasma levels at 8, 16, and 24 weeks in patients treated with these regimens (closed as of 4/16/2009).
  • Compare estradiol serum levels at 8, 16, and 24 weeks in patients treated with these regimens (closed as of 4/16/2009).

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to prior adjuvant tamoxifen therapy (yes vs no). Patients are randomized to 1 of 2 treatment arms.

  • Arm I: Patients receive oral anastrozole once daily on days 1-28.
  • Arm II: Patients receive oral anastrozole as in arm I. Patients also receive fulvestrant intramuscularly on days 1, 14, and 28 during course 1 and then on day 28 of the subsequent courses.

In both arms, courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.

Patients are followed for up to 4 years.

PROJECTED ACCRUAL: A total of 690 patients (345 per treatment arm) will be accrued for this study within 3 years.


Breast Cancer stage IV breast cancer recurrent breast cancer Fulvestrant Anastrozole Estradiol


For females ages 18 years and up


  • Histologically confirmed breast cancer meeting 1 of the following criteria:
  • Metastatic disease (M1)
  • Multiple sites of new disease that is clinically obvious metastatic disease(e.g., multiple sites of new osseous disease)
  • Measurable or nonmeasurable disease
  • No known brain or CNS metastases
  • Hormone receptor status:
  • Estrogen-receptor positive* AND/OR
  • Progesterone-receptor positive NOTE: Positivity defined as estrogen binding of> 10 fmol/mg cytosol protein by ligand binding assay or positive by immunohistochemistry



  • Not specified


  • Female

Menopausal status

  • Postmenopausal, as defined by 1 of the following:
  • Prior bilateral oophorectomy
  • More than 12 months since last menstrual period with no prior hysterectomy
  • At least 55 years of age with prior hysterectomy
  • Under 55 years of age with a prior hysterectomy without oophorectomy and with estradiol and follicle-stimulating hormone levels consistent with menopause

Performance status

  • Zubrod 0-2

Life expectancy

  • Not specified


  • No bleeding diathesis (e.g., disseminated intravascular coagulation or clotting factor deficiency)


  • INR ≤ 1.6


  • Not specified


  • HIV negative
  • No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, or adequately treated stage I or II cancer currently in complete remission


Biologic therapy

  • No prior immunotherapy for recurrent or metastatic disease


  • No prior chemotherapy for recurrent or metastatic disease
  • More than 12 months since prior adjuvant or neoadjuvant chemotherapy
  • No concurrent chemotherapy for malignancy

Endocrine therapy

  • Prior adjuvant hormonal therapy allowed
  • At least 12 months since prior adjuvant luteinizing hormone-releasing hormone (LHRH)analogues
  • Menstrual periods must not have resumed since LHRH therapy
  • More than 12 months since prior adjuvant or neoadjuvant aromatase inhibitors (e.g.,anastrozole, letrozole, or exemestane)
  • More than 12 months since prior fulvestrant
  • No prior hormonal therapy for recurrent or metastatic disease
  • No other concurrent hormonal therapy for malignancy
  • No concurrent hormone replacement therapy


  • Not specified


  • Not specified


  • No long-term anticoagulant therapy (except antiplatelet therapy)


  • CCOP - Santa Rosa Memorial Hospital
    Sana Rosa, California, 95405, United States
  • University of California Davis Cancer Center
    Sacramento, California, 95817, United States
  • Tibotec Therapeutics - Division of Ortho Biotech Products, LP
    Marysville, California, 95901, United States
  • Tahoe Forest Cancer Center
    Truckee, California, 96161, United States
  • Glendale Memorial Hospital Comprehensive Cancer Center
    Glendale, California, 91204, United States
  • City of Hope Comprehensive Cancer Center
    Duarte, California, 91010-3000, United States
  • USC/Norris Comprehensive Cancer Center and Hospital
    Los Angeles, California, 90089-9181, United States
  • Loma Linda University Cancer Institute at Loma Linda University Medical Center
    Loma Linda, California, 92354, United States
  • University Medical Center of Southern Nevada
    Las Vegas, Nevada, 89102, United States
  • CCOP - Nevada Cancer Research Foundation
    Las Vegas, Nevada, 89106, United States


in progress, not accepting new patients
Start Date
Completion Date
Southwest Oncology Group
Phase 3
Study Type
Last Updated
February 1, 2017