 - Patients must have none of the following: Active infection Known HIV infection Past history of anaphylaxis following exposure to rat or mouse CDR-grafted humanised monoclonal antibodies Less than 3 weeks since prior chemotherapy Use of prior investigational agents within 6 weeks Pregnancy or lactation Uncontrolled diabetes mellitus Uncontrolled hypertension Active peptic ulcer disease Other severe concurrent diseases or mental disorders Serum urea or creatinine more than twice the upper limit of normal unless due to uretic obstruction or renal infiltration by CLLSLL Serum bilirubin more than twice the upper limit of normal unless due to haemlysis or liver infiltration with CLLSLL Persisting severe cytopenias due to previous therapy rather than disease neutrophils 0.5 x 109l or platelets 50 x 10l 