Symptomatic congestive heart failure of New York heart Association Class III or IV Unstable angina pectoris, myocardial infarction within 6 months of start of study drug, serious uncontrolled cardiac arrhythmia or any other clinically significant cardiac disease Severely impaired lung function with a previously documented spirometry and DLCO that is 50% of the normal predicted value and/or 02 saturation that is 88% or less at rest on room air Uncontrolled diabetes Active (acute or chronic) or uncontrolled severe infections Liver disease such as cirrhosis, chronic active hepatitis or chronic persistent hepatitis A known history of HIV seropositivity as reported by the patient Impairment of gastrointestinal function or gastrointestinal disease (e.g., ulcerative disease, uncontrolled nausea, vomiting, diarrhea, malabsorption syndrome or small bowel resection) Patients with an active, bleeding diathesis