Arimidex With or Without Faslodex In Postmenopausal Women With HR Positive Breast Cancer (PACT001)

Inclusion Criteria:

• All subjects must be female.

• Postmenopausal status, defined as any one of the following criteria:

  • Documented history of bilateral oophorectomy.
  • Age 60 years or more.

  • Age 45 to 59 and satisfying one or more of the following criteria:

    • Amenorrhea for at least 12 months and intact uterus.
    • Amenorrhea for less than 12 months and a follicle stimulating hormone (FSH) and estradiol concentration within postmenopausal range including: patients who have had a hysterectomy and patients who have received hormone replacement.
• Patients must have histologically confirmed invasive breast cancer with a primary tumor of 3 cm or more in greatest dimension as measured by clinical examination.
• Estrogen receptor and/or progesterone receptor positive disease.
• Patients must not have received any prior treatment for current or newly diagnosed breast cancer.
• Patients must have not received previous treatment with any of the study medications or similar drugs.
• No use of selective estrogen receptor modulators (SERM) such as raloxifene or similar agents in the past 2 years.
• WHO performance status of 0, 1, or 2.

• Adequate organ function defined as follows:

  • Adequate renal function, defined by a serum creatinine within 3 times the upper limits of normal.
  • Adequate liver function, defined by total bilirubin, AST, ALT, and alkaline phosphatase within 3 times the upper limits of normal.
  • Adequate bone marrow function, defined as a WBC greater than 3.0 ml, PLT greater than 75,000/ul, Hb greater than 9 gm/l.
• Willing to undergo breast core biopsies as required by the study protocol. - Ability to understand and sign a written informed consent for participation in the trial.
• Life expectancy of at least 1 year.

Exclusion Criteria:

• Premenopausal status.
• Other coexisting malignancies with the exception of basal cell carcinoma or cervical cancer in situ.
• Patients with brain metastasis.
• WHO performance status of 3 or 4.
• Is judged by the investigator, uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, significant cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
• Evidence of any other significant clinical disorder or laboratory finding that makes it undesirable for the subject to participate in the clinical trial. - Concurrent treatment with estrogens or progestins. Patients must stop these drugs at least two weeks prior to study entry.
• Treatment with a non-approved or investigational drug within 30 days before Day 1 of study treatment.
• Platelet count less than 75,000.
• In the opinion of the investigator, bleeding diathesis or anticoagulation therapy that would preclude intramuscular injections.
• History of hypersensitivity to castor oil.
• Any evidence of clinically active interstitial lung disease (patients with chronic stable radiographic changes who are asymptomatic need not be excluded) - Patients with recurrent breast cancer.
• Patients with contralateral second primary breast cancers are eligible.