DISEASE CHARACTERISTICS:

• Cytogenetically confirmed chronic myelogenous leukemia (CML) by standard conventional cytogenetic analysis of bone marrow*

  • Newly diagnosed disease (within the past 6 months) NOTE: *FISH cannot be used

• In chronic phase, as defined by the following:

  • Less than 15% blasts in peripheral blood and bone marrow
  • Less than 30% blasts plus promyelocytes in peripheral blood and bone marrow
  • Less than 20% basophils in peripheral blood
  • Platelet count ≥ 100,000/mm^3
  • No evidence of extramedullary leukemic involvement, except for hepatosplenomegaly

• Philadelphia chromosome-positive disease as demonstrated by (9;22) translocation (presence of Bcr-Abl)

  • A review of ≥ 20 metaphases is required
• No previously documented T315I mutations

PATIENT CHARACTERISTICS:

• ECOG performance status 0-2
• Total bilirubin < 1.5 times upper limit of normal (ULN)
• AST and ALT < 2.5 times ULN
• Estimated glomerular filtration rate ≥ 30 mL/min
• Serum amylase and lipase ≤ 1.5 times ULN
• Alkaline phosphatase ≤ 2.5 times ULN (unless related to CML)
• Potassium ≥ lower limit of normal (LLN)
• Magnesium ≥ LLN
• Phosphorous ≥ LLN
• Total calcium ≥ LLN (corrected for serum albumin)
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

• No impaired cardiac function including, but not limited to, any of the following:

  • LVEF < 45% or < LLN by ECHO
  • Inability to determine the QT interval on ECG
  • Complete left bundle branch block
  • Congenital long QT syndrome or a known family history of long QT syndrome
  • History of or presence of clinically significant ventricular or atrial tachyarrhythmias
  • Clinically significant resting bradycardia (< 50 beats/min)
  • QTc > 450 msec on an average of 3 serial baseline ECGs (using the QTcF formula)
  • Clinically documented myocardial infraction within the past 12 months
  • Unstable angina within the past 12 months
  • Other clinically significant heart disease (e.g., congestive heart failure or uncontrolled hypertension)
• No severe or uncontrolled medical condition (e.g., uncontrolled diabetes or active or uncontrolled infection)
• No history of significant congenital or acquired bleeding disorder unrelated to CML
• No history of non-compliance to medical regimens
• No other primary malignancy unless it is neither currently clinically significant nor requiring active intervention
• No impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of the study drug (e.g., ulcerative disease, uncontrolled nausea, vomiting, diarrhea, malabsorption syndrome, small bowel resection, or gastric bypass surgery)
• No acute pancreatitis within the past year
• No history of chronic pancreatitis
• No acute or chronic liver, pancreatic, or severe renal disease considered unrelated to CML

PRIOR CONCURRENT THERAPY:

• No prior therapy for CML other than hydroxyurea and/or anagrelide
• Prior imatinib mesylate allowed provided it was administered for ≤ 14 days
• More than 30 days since prior and no other concurrent investigational agents
• More than 4 weeks since prior major surgery and recovered
• No other concurrent anticancer agents, including chemotherapy and biologic agents
• No concurrent strong CYP3A4 inhibitors (e.g., erythromycin, ketoconazole, itraconazole, voriconazole, clarithromycin, telithromycin, ritonavir, mibefradil)
• No concurrent strong CYP3A4 inducers (e.g., dexamethasone, phenytoin, carbamazepine, rifampin, rifabutin, rifapentin, phenobarbital, St. John's wort)
• No concurrent medications that have the potential to prolong QT interval
• No concurrent grapefruit, star fruit, Seville oranges, or their derivatives