A Study of Trastuzumab-MCC-DM1 in Patients With HER2- Positive Locally Advanced or Metastatic Breast Cancer

Inclusion Criteria:

Histologically or cytologically documented breast cancer
Locally advanced or metastatic breast cancer
HER2-positive breast cancer documented as FISH-positive, IHC 3 + or CISH-positive by local laboratory assessment
Histologically or cytologically confirmed invasive breast cancer: incurable, unresectable, locally advanced breast cancer previously treated with multimodality therapy or metastatic breast cancer
Prior treatment for breast cancer in the adjuvant, unresectable, locally advanced, or metastatic setting must include both: a taxane, alone or in combination with another agent, and Trastuzumab, alone or in combination with another agent in the adjuvant, unresectable, locally advanced, or metastatic setting
Documented progression of incurable unresectable, locally advanced, or metastatic breast cancer during their most recent treatment regimen
Progression must occur during or after most recent treatment for locally advanced/metastatic breast cancer or within 6 months after completing adjuvant therapy
Adequate hematologic and end organ function
Agreement to use an effective form of birth control throughout the study
Life expectancy ≥ 90 days as assessed by the investigator

Exclusion Criteria:

Less than 14 days from the first study treatment since the last anti-cancer therapy, including chemotherapy, biologic, experimental, immune, hormonal or endocrine therapy
Prior T-DM1 therapy
History of exposure to cumulative doses of select anthracyclines
History of intolerance or hypersensitivity to trastuzumab, murine proteins, or any of the excipients, that resulted in trastuzumab being permanently discontinued
Brain metastases that are untreated or progressive or currently require any type of therapy, including radiation, surgery, and/or steroids to control symptoms from brain metastases within 30 days before the first study treatment
Peripheral neuropathy of Grade ≥ 3 per National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE), version 4.0, at the time of the first study treatment
History of clinically significant cardiac dysfunction
Current known active infection with HIV, hepatitis B virus, or hepatitis C virus
Current severe, uncontrolled systemic disease
Major surgical procedure or significant traumatic injury within 28 days prior to first study treatment
Pregnancy or lactation

NOTE: The site selection process has been completed. Patients can enroll at participating sites.