Treatment of Polycythemia Vera With Gleevec

Inclusion Criteria: * Patients have diagnosis of Polycythemia Vera (PV). Patients may have newly diagnosed PV. * Patients may have previously interferon-alfa treated PV with documented resistance, refractoriness or intolerance to interferon-alfa. * Patients may have PV with inadequate control on hydroxyurea. * Performance status of 0, 1, or 2 * Adequate end organ function, defined as the following: 1. total bilirubin \<1.5 x upper limit of the normal range (ULN) 2. SGOT (AST) and SGPT (ALT) \< 2.5 x ULN 3. creatinine \< 1.5 x ULN 4. ANC \> 1.5 x 109/L * Written voluntary informed consent. Exclusion Criteria: * Female patients who are pregnant or breast-feeding. * Patients receiving busulfan within 6 weeks of Study Day 1. * Patients receiving interferon-alpha within 4 weeks of Study Day 1. * Patients receiving hydroxyurea within 2 weeks of Study Day 1. * Patients with Grade III or IV cardiac problems as defined by the New York Heart Association Criteria. * Patients with a history of non-compliance to medical regimens or who are considered potentially unreliable. * Patients previously treated with Gleevec. * Serum erythropoietin level \> or = 25 units/microliter * Abnormal O2 saturation (by pulse oximetry) or arterial pO2 (by arterial blood gas).