Before receiving the study drug on Day 1 of Cycles 2-18, you will have a physical exam, neurological exam, and a performance status evaluation. You will also be asked about any drugs, treatments, or herbal medicines you are taking. Blood (less than 2 tablespoons) and urine will be collected for routine tests. You will have an ECG. Before Cycles 4, 6, 8, 10, 12, 14,16, and 18, you will have a MUGA scan or an echocardiogram. Once you have completed the tests, you will receive the study drug in the same manner as Cycle 1.