Oral Deforolimus With Trastuzumab for Patients With HER2-positive Trastuzumab-Refractory Metastatic Breast Cancer (8669-009)

Inclusion Criteria:

* Female, 18 years of age or older
* Histologically confirmed HER2-positive metastatic breast cancer
* Trastuzumab-resistance
* Measurable disease, according to RECIST guidelines
* ECOG performance status less than or equal to 1
* Life expectancy greater than 3 months
* No prior treatment with temsirolimus, everolimus, rapamycin, or any other mTOR inhibitor
* At least 4 weeks must have lapsed between prior investigational therapy, chemotherapy or radiotherapy, and the first dose of ridaforolimus
* Left ventricular ejection greater than or equal to 50%
* Adequate cardiovascular function
* Adequate hematological, hepatic, and renal function
* Serum cholesterol less than or equal to 350 mg/dL and triglycerides less than or equal to 400 mg/dL
* Negative pregnancy test within 7 days prior to first dose of study drug and must use an approved contraceptive method from screening to 30 days after the last dose of study drug
* Availability and patient consent to obtain archival tissue samples
* Signed informed consent

Exclusion Criteria:

* Inadequate recovery from any prior surgical procedure or having undergone any major surgery within 2 weeks before trial entry
* Grade 1 or Grade 2 hypersensitivity reactions to prior trastuzumab therapy if these reactions prevented further trastuzumab administration
* Grade 3 or Grade 4 hypersensitivity reaction to prior trastuzumab
* Symptomatic intrinsic lung disease or extensive tumor involvement of the lungs, resulting in dyspnea at rest
* Known allergy to macrolide antibiotics
* Pregnant or breast-feeding
* Know history of HIV
* Diagnosis of brain metastasis or leptomeningeal carcinomatosis within 3 months
* Other malignancies within the past 3 years, except for adequately treated carcinoma of the cervix or basal or squamous cell carcinoma of the skin
* Active infection requiring prescription intervention
* Newly diagnosed or poorly controlled Type 1 or 2 diabetes
* Other concurrent illness which, in the Investigator's judgment, would either compromise the patient's safety or interfere with the evaluation of the safety of the study drug
* Concurrent treatment with medications that strongly induce or inhibit cytochrome P450.
* Any condition that renders patient unable to fully understand and provide informed consent and/or comply with the protocol