Inclusion Criteria:

1. Patients must be adult (age ≥ 18 years age) post-menopausal* women

2. Patients must be diagnosed with advanced breast cancer (histologically or cytological
confirmation required) i.e. TNM stage III or IV disease (locally advanced or
metastatic breast cancer) or locoregional recurrent disease, not suitable for
treatment by local surgery or radiation therapy

3. Measurable or evaluable disease

4. Patients with ER/PR positive tumour or ER/PR unknown status

5. Patients must be suitable for endocrine treatment with anastrozole

6. Prior adjuvant chemotherapy or endocrine therapy for early breast cancer is allowed,
provided such treatment was completed at least twelve months prior to study
enrollment

7. Performance status 0-2 (As per WHO Classification)

8. Concurrent use of bisphosphonates is permitted.

9. Patients must give their written informed consent for participation in the study

Exclusion Criteria:

1. Patients with tumors known to be estrogen and progesterone receptor-negative.

2. Estrogen hormone replacement therapy, concurrently or within 6 weeks before
randomization

3. Extensive visceral involvement (significant hepatic involvement, brain metastasis or
pulmonary involvement > 50% of the lungs); serum liver enzymes SGOT and SGPT should
be no greater than five times the upper limit of the reference range

4. Patients received bone marrow transplantation before randomization

5. Any concurrent medical illness (uncontrolled cardiac disease or diabetes mellitus) or
laboratory abnormalities that would compromise safety or prevent interpretation of
results

6. An estimated survival of less than 3 months from the start of Study drug treatment
based on clinical judgment.

7. Any systemic investigational drug within the thirty days of enrollment into study