Conditions: HER2-positive Breast Cancer Recurrent Breast Cancer Stage IIIA Breast Cancer Stage IIIB Breast Cancer Stage IIIC Breast Cancer Stage IV Breast Cancer
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 17
Healthy volunteers: no

Brief summary:
The purpose of this study is to see whether a combination of two different drugs - trastuzumab-MCC-DM1 (T-DM1) and BYL719 is safe, and if it might be effective in treating metastatic breast cancer. T-DM1 is a type of drug that contains an antibody (trastuzumab) linked to chemotherapy. The antibody in T-DM1 targets a marker on breast cancer cells called HER2, which allows the drug to go directly to the cancer cells. The use of T-DM1 in this study is considered standard treatment for the type of cancer in this study. Participants in this study have already been treated with trastuzumab and chemotherapy in the past, and their cancer has gotten worse in spite of those treatments. BYL719 is an oral drug (taken by mouth) that the researchers think may help T-DM1 to work better.

Detailed description:
PRIMARY OBJECTIVES:

I. Determine safety, tolerability, feasibility, and the maximum-tolerated dose (MTD) of dose-escalating BYL719 in combination with ado-trastuzumab emtansine (T-DM1) in patients with HER2-positive metastatic breast cancer (MBC) after progression on trastuzumab and taxane-based therapy.

SECONDARY OBJECTIVES:

I. Evaluate pharmacokinetics (PK) of BYL719 administered in combination with T-DM1.

II. Assess any preliminary evidence of efficacy of BYL719 and T-DM1 in combination in patients with HER2-positive MBC.

TERTIARY OBJECTIVES:

I. Explore efficacy in patients whose tumors have an alteration (mutation or amplification) of the PIK3CA gene and decrease of phosphatase and tensin homolog gene (PTEN) expression. (Optional) II. Examine other v-akt murine thymoma viral oncogene homolog 1 (Akt)/mechanistic target of rapamycin (mTOR) downstream markers by immunohistochemistry. (Optional)

OUTLINE: This is a dose-escalation study of PI3K inhibitor BYL719.

Patients receive PI3K inhibitor BYL719 orally (PO) daily on days 1-21 and ado-trastuzumab emtansine (T-DM1) intravenously (IV) over 30-90 minutes on day 1. Courses repeat every 21 days in the absence of disease progression or unacceptable toxicity, or at the discretion of the treating physician.

After completion of study treatment, patients are followed up every 3 months.

Arms:
arm 1: Patients receive PI3K inhibitor BYL719 PO daily on days 1-21 and ado-trastuzumab emtansine IV over 30-90 minutes on day 1. Courses repeat every 21 days in the absence of disease progression or unacceptable toxicity.

Interventions: intervention 1: PI3K inhibitor BYL719 intervention 2: ado-trastuzumab emtansine intervention 3: pharmacological study intervention 4: laboratory biomarker analysis
Intervention descriptions: intervention 1: Given PO intervention 2: Given IV intervention 3: Correlative studies intervention 4: Optional correlative studies

Protocol document: