- At study entry, patients who were treated with: imatinib mesylate within the past 48 hours; interferon-alpha within the past 48 hours; homoharringtonine within the past 14 days; low-dose cytosine arabinoside within 7 days, moderate dose within 14 days, or high dose within 28 days; etoposide, anthracyclines, or mitoxantrone within 21 days; busulfan within the past six weeks