Conditions: Breast Neoplasms Endocrine Breast Diseases Neoplasm Metastasis
Keywords: endocrine resistant everolimus lapatinib letrozole
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 7
Healthy volunteers: no

Brief summary:
About a third of patients with breast cancer are usually treated by hormone pills called tamoxifen and aromatase inhibitors. Aromatase inhibitors are drugs that stop female hormone production. Female hormone or estrogen is an important hormone for the growth of breast cancer cells. Letrozole is one of the aromatase inhibitors that is approved by the FDA and has been used to treat breast cancer since 1997. However, hormone pills usually work for about 6-10 months in most patients. Later on, breast cancer will start to grow again. This condition when hormone pills or endocrine therapy no longer work is called "endocrine resistant" breast cancer. The scientists here at University of Maryland have discovered how these cancer cells can become resistant to hormone pills. In our laboratory tests, the investigators found that lapatinib and everolimus can reverse this resistance and make letrozole work again. However, it is not known if the drugs can reverse the resistance in humans.

The purpose of this study is to find out whether the combination of letrozole, lapatinib, and everolimus is effective in women with breast cancer when hormone pills no longer work.

Lapatinib is an anti-cancer drug that is already approved by the Food and Drug Administration (FDA). It is the standard of care for the treatment of a particular type of breast cancer called human epithelial growth factor receptor 2 (HER2)-positive breast cancer. HER2 is a protein involved in the growth of some cancer cells. This study will also include patients with HER2-negative breast cancer. This means that the cancer cells in these patients do not depend on the HER2 protein. The use of lapatinib in these patients is considered experimental.

Everolimus is also an anti-cancer drug that is approved by the FDA for kidney cancer. Initial studies in mice and later studies in women with breast cancer have shown that everolimus may also slow the growth of breast cancer. The use of everolimus is experimental in this study.

Detailed description:
This is a single-institution clinical trial. Patients will be stratified according to the HER2 status:

Group 1: HER2-positive in the tumor tissue Group 2: HER2 negative in the tumor tissue

In the first part of the study, all of the patients will receive the combination of lapatinib 1,500 mg/day and letrozole 2.5 mg/day. We do not expect any significant toxicity from this combination since the previous study of lapatinib and letrozole showed that this combination is safe with no grade 3-4 toxicities observed. Restaging scans (CT scan, MRI, or bone scan) will be obtained after every 12 weeks of treatment. In those patients who progress from any group, everolimus 5 mg/day will be added to letrozole and lapatinib will be reduced to 1,250 mg/day as per the SWOG phase I study of lapatinib and everolimus. The outcome of each group will continue to be assessed separately. We do not expect to see additional serious toxicity from adding everolimus to the combination of lapatinib and letrozole. All of the treatment will be continued until disease progression.

Arms:
arm 1: Lapatinib 1,500 mg/day + letrozole 2.5 mg/day until progression followed by everolimus 5 mg/day + letrozole 2.5 mg/day + lapatinib 1,250 mg/day.

Interventions: intervention 1: letrozole intervention 2: lapatinib intervention 3: everolimus
Intervention descriptions: intervention 1: Drug is are to be taken orally. 2.5 mg once daily intervention 2: Drug is to be taken orally. 1,500 mg once daily in the first part of the study and then 1,250 mg once daily in the second part of the study (after initial progression) intervention 3: Drug is to be taken orally. 5 mg once daily.

Protocol document: