- Class III or IV heart failure as defined by the New York Heart Association (NYHA) functional classification system. Subjects who have experienced untreated and/or uncontrolled cardiovascular conditions and/or have symptomatic cardiac dysfunction (unstable angina, congestive heart failure, myocardial infarction within the previous year or cardiac ventricular arrhythmias requiring medication, history of 2nd or 3rd degree atrioventricular conduction defects). Subjects with a significant cardiac history (even if controlled) or prior doxorubicin exposure are required to have a Left Ventricular Ejection Fraction (LVEF) >=50%.