 3. Co-existing active infection or any co-existing medical condition likely to interfere with trial procedures, including significant cardiovascular disease New York Heart Association Class III or IV cardiac disease, myocardial infarction within the past 6 months, unstable angina, congestive heart failure requiring therapy, unstable arrhythmia or a need for anti-arrhythmic therapy, or evidence of ischemia on ECG, marked baseline prolongation of QTQTc corrected QT interval interval, e.g., repeated demonstration of a QTc interval 500 msec; Long QT Syndrome; the required use of concomitant medication on PXD101 infusion days that may cause Torsade de Pointes. 