imatinib mesylate in treating patients with myelofibrosis

Conditions: Chronic Myeloproliferative Disorders

Summary: rationale: imatinib mesylate may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. purpose: this phase ii trial is studying the side effects of imatinib mesylate and how well it works in treating patients with myelofibrosis.

objectives: primary * determine the safety, efficacy, and tolerability of imatinib mesylate in patients with myelofibrosis with myeloid metaplasia. * determine the 3-, 6-, and 12-month major and minor erythroid response rates in patients treated with this drug. secondary * determine reduction in marrow fibrosis in patients treated with this drug. * determine decrease in spleen size in patients treated with this drug. outline: this is a multicenter, open-label, nonrandomized, pilot study. patients receive oral imatinib mesylate once daily for 1 year in the absence of disease progression or unacceptable toxicity. patients who do not experience a minor erythroid response or a 50% reduction in spleen size after 6 months of treatment are removed from the study. patients experiencing clinical benefit (e.g., ongoing erythroid response) after 1 year of treatment may continue treatment with imatinib mesylate as above at the discretion of the principal investigator. projected accrual: a total of 20 patients will be accrued for this study.

Eligibility criteria:
disease characteristics: * diagnosis of myelofibrosis with myeloid metaplasia (mmm), defined by all of the following: * leukoerythroblastic blood picture * fibrosis involving \> 1/3 sectional area of bone marrow biopsy * splenomegaly (unless patient has undergone prior splenectomy) * philadelphia chromosome negative * no myelodysplastic syndrome * no systemic disorders associated with marrow fibrosis * red blood cell transfusion dependent, defined by 1 of the following: * patient has required ≥ 2 units of red blood cells every 4 weeks within the past 8 weeks * hemoglobin ≤ 8 g/dl on ≥ 3 occasions (≥ 2 weeks apart ) over the past 8 weeks * no evidence of disease transformation to acute myelogenous leukemia, defined as \> 20% blasts in bone marrow and/or peripheral blood patient characteristics: performance status * ecog 0-3 life expectancy * not specified hematopoietic * absolute neutrophil count \> 1,000/mm\^3 * platelet count \> 50,000/mm\^3 hepatic * bilirubin ≤ 1.5 times upper limit of normal (uln) * ast or alt ≤ 2 times uln (unless due to extramedullary hematopoiesis in the liver) renal * creatinine ≤ 1.5 times uln cardiovascular * no new york heart association grade iii-iv heart disease other * not pregnant or nursing * negative pregnancy test * fertile patients must use effective barrier method contraception during and for 3 months after completion of study treatment * no serious, uncontrolled medical condition * no patients who are considered potentially unreliable or with a history of noncompliance to medical regimens prior concurrent therapy: biologic therapy * more than 2 weeks since prior interferon alfa chemotherapy * no concurrent chemotherapy except hydroxyurea to control elevated blood counts endocrine therapy * more than 4 weeks since prior corticosteroids, danazol, or other androgens for mmm other * more than 4 weeks since other prior treatment for mmm * no other concurrent experimental drug therapy for mmm

Keywords: chronic idiopathic myelofibrosis polycythemia vera essential thrombocythemia