Anti-Tac for Treatment of Leukemia

ELIGIBILITY CRITERIA: Population Base. Patients diagnosed with smoldering or chronic human T-lymphotropic virus type 1 (HTLV-I)- associated adult T-cell leukemia. INCLUSION CRITERIA: Patients must have serum antibodies directed to HTLV-I. All patients must have a histologically confirmed diagnosis of adult T-cell leukemia/lymphoma. At least 5 percent of each patient's peripheral blood, lymph node, pulmonary or dermal malignant cells must react with the anti-Tac mAb as determined by immunofluorescent staining or, alternatively, the serum-soluble interleukin 2 (IL-2) receptor levels must be greater than 1,000 units/ml (normal geometric mean, 235; with a 95% confidence interval of 112 to 502 units/mL). Smoldering or chronic stage Tac-expressing adult T-cell leukemia defined by the Shimomyama Criteria (37) are eligible. To be diagnosed as smoldering Adult T-cell Leukemia (ATL), the patient must have a normal lymphocyte count (less than 4 times 10^3/mm^3), less than or equal to 5 percent abnormal lymphocytes on morphologic examination of the peripheral blood smear or on fluorescence activated cell sorting (FACS) analysis (cells with a homogenous staining pattern and a greater than 1 log increase in the magnitude of fluorescence emission of the anti-Tac peak over background expression), no hypercalcemia, lactate dehydrogenase less than or equal to 1.5 times the upper limit of normal, no lymphadenopathy, no involvement of extra nodal organs except skin or lung and no malignant pleural effusion or ascites. If the abnormal lymphocyte count is less than 5 percent, the patient must have at least one histologically proven skin ATL lesion to be diagnosed as smoldering ATL. Patients with >5% of circulating lymphocytes that are abnormal are considered to have measurable disease. The patient must have a granulocyte count of at least 500/mm^3 and a platelet count of 25,000/mm^3. Patients must have a creatinine of less than 3.0 mg/dl. Patients must have a Karnofsky performance score of greater than 60 percent. ATL patients without, as well as those with, previous chemotherapy will be eligible for inclusion in the study. Patients with previous therapy with a monoclonal antibody including anti-Tac will be eligible for the study provided that they do not have a positive HAHA (human antibody to humanized anti-Tac) value (i.e., such patients must have a value greater than 250 ng/ml). Omission of cytotoxic chemotherapy for ATL for 3 weeks prior to entry into the trial is required. However, patients receiving corticosteroids will not be excluded. Patients must have a life expectancy of greater than 2 months. Eligible patients must be greater than or equal to 10 years old. There is no upper age limit. Patients over the age of 18 years must be able to understand and sign an Informed Consent form. Eligible minors greater than or equal to 10 years old must give assent to participate in this study. EXCLUSION CRITERIA: Patients with symptomatic central nervous system disease that is due to the adult T-cell leukemia will be excluded. However, patients that have both ATL and another HTLV-I-associated disease, tropical spastic paraparesis (TSP), will be included. Furthermore, Tac-expressing T cells may be present in the cerebrospinal fluid (CSF) as long as the patient does not have symptomatic central nervous system (CNS) disease. Pregnant and/or nursing patients are not eligible for the study. Human immunodeficiency virus (HIV) positive patients are excluded from the study. Patients with serum glutamic oxaloacetic transaminase (SGOT) or serum glutamic pyruvic transaminase (SGPT) values 5.0-fold greater than the upper limit of normal or bilirubin greater than 2.9 mg/dl will be excluded. If a liver function test is judged to be elevated due to the underlying ATL, this parameter will be considered an unevaluable parameter for toxicity determinations. Acute or Lymphoma stage HTLV-1 associated adult T cell leukemia.