Phase II Study of Rituximab in Patients With Immune Thrombocytopenic Purpura

PROTOCOL ENTRY CRITERIA: --Disease Characteristics-- Clinically confirmed immune thrombocytopenic purpura (ITP) Platelet count less than 75,000/mm3 on two occasions at least 1 week apart within past month Normal to increased numbers of megakaryocytes on bone marrow examination within past 6 months Failed prior steroid therapy (i.e., unable to achieve sustained platelet count greater than 75,000/mm3) No drug associated ITP No B cell malignancies No evidence of disseminated intravascular coagulation (DIC) --Prior/Concurrent Therapy-- Endocrine therapy: Concurrent steroids allowed as long as platelet count is less than 75,000/mm3 and dose is not changed within past 2 weeks or during study Other: No other concurrent medical therapy for immune thrombocytopenia purpura (ITP) At least 2 weeks since prior therapy for ITP (except steroids) At least 4 weeks since prior cyclosporine --Patient Characteristics-- Performance status: ECOG 0-2 Life expectancy: At least 6 months Renal: Creatinine no greater than 2.0 mg/dL Cardiovascular: No congestive heart failure or symptomatic coronary insufficiency Other: No clinically significant bleeding (i.e., other than mild mucosal bleeding or petechiae) No sepsis or fever No active infection requiring therapy No active chronic viral infection HIV negative No other concurrent or prior malignancy within past 5 years except squamous or basal cell carcinoma of the skin or carcinoma in situ of the cervix Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception