Study of Oral Ridaforolimus in Combination With Standard Chemotherapy for Soft Tissue Sarcoma

Inclusion Criteria: * Advanced or metastatic soft tissue sarcoma with histological or cytological proven disease. No more than 2 lines of chemotherapy in the metastatic setting in the dose escalation phase, and no more than one line of prior therapy in the expansion phase. * ECOG performance status of ≤ 1 * A minimum life expectancy \> 3 months * At least 4 weeks must have elapsed between prior investigational therapy, chemotherapy or radiotherapy and the first dose of ridaforolimus * Adequate hematological, hepatic and renal function (hemoglobin ≥ 9g/dl, absolute neutrophil count \[ANC\] ≥ 1.5 x 109/L; platelets ≥ 100 x 109/L; bilirubin ≤ ULN; alkaline phosphatase ≤ 2.5 x ULN; AST, ALT ≤ 2.5 x ULN; albumin ≥ 2.5mg/dL; creatinine ≤ 1.5 x ULN) * Serum cholesterol ≤ 350 mg/dL and triglycerides ≤400 mg/dL * Signed informed consent * Women of childbearing potential must have a negative serum pregnancy test within 7 days prior to start of therapy and must use an approved contraceptive method as appropriate from the time of screening until 30 days after the last dose of study drug. Exclusion Criteria: * Uncontrolled brain metastases, spinal cord compression, or carcinomatous meningitis. * Clinically significant unexplained bleeding within 28 days prior to entering the trial * Uncontrolled systemic vascular hypertension * Clinically significant cardiovascular disease * Newly diagnosed (within 3 months of enrollment) or poorly controlled type 1 or 2 diabetes * Have received \>350 mg/m2 total dose of Doxorubicin * Active infection requiring prescribed intervention * Other concurrent illness * Major surgery within 28 days before trial entry, or incompletely healed surgical incision; minor surgery or procedures within 7 days * Previous anthracycline lifetime exposure more than 350 mg/m2 would exclude patient form AIM Arm enrollment * Pregnant or breastfeeding * Known allergy to macrolide antibiotics * Concurrent treatment with medications that induce or inhibit cytochrome P450 (CYP3A). * Known history of HIV sero-positivity