Overcoming Endocrine Resistance in Metastatic Breast Cancer

Inclusion Criteria:

1. Provision of written informed consent
2. Histological/cytological confirmation of breast cancer
3. Documented positive hormone receptor status (ER+ve and/or PgR+ve) of primary or metastaic tumor issue, according to the local laboratory parameters
4. Postmenopausal women
5. Confirmed progression of disease after an adjuvant therapy or a therapy for metastatic disease with an aromatase inhibitors
6. Patients demonstrating prior response to AI therapy
7. Patients with measurable disease as per RECIST criteria /Patients with bone lesions, lytic or mixed (lytic + sclerotic), in the absence of measurable disease as defined by RECIST criteria.
8. May have received prior radiotherapy as treatment for primary or metastatic tumour; however, is not required for study entry;
9. Life expectancy of at least 8 months
10. WHO performance status 0, 1 or 2
11. Patients with a history of other malignancies are eligible if they have been disease-free for at least 5 years and are deemed by the investigator to be at low risk for recurrence.
12. Are able to swallow and retain oral medication;
13. Are able to complete all screening assessments as outlined in the protocol;
14. Patients must have normal organ and marrow function
15. Left ventricular ejection fraction (LVEF) within the institutional normal range

Exclusion Criteria:

1. Previous therapy with Fulvestrant and/or Lapatinib;
2. Patients with HER 2 overexpressing, either IHC 3+ or FISH +;
3. Concurrent non study anti-cancer therapy (
4. Have unresolved or unstable, serious toxicity from prior administration
5. Have malabsorption syndrome,
6. Have a concurrent disease or condition that would make the patient inappropriate for study participation,
7. Have an active or uncontrolled infection;
8. Have dementia, altered mental status, or any psychiatric condition that would prohibit the understanding or rendering of informed consent;
9. Have a known history of uncontrolled or symptomatic angina, arrhythmias, or CHF;
10. Receive concurrent treatment with an investigational agent or participate in another clinical trial;
11. Receive concurrent treatment with prohibited medications
12. Used an investigational drug within 30 days or 5 half-lives, whichever is longer, preceding the first dose of study medication;
13. Have a known immediate or delayed hypersensitivity reaction or idiosyncrasy to drugs chemically related to fulvestrant, aromatase inhibitors or lapatinib or excipients.