[Phase II clinical study of SH L 573 (fludarabine phosphate) in patients with chronic lymphocytic leukemia]

We conducted a multicenter phase II clinical study of fludarabine phosphate, a new purine nucleotide analogue, in patients with chronic lymphocytic leukemia (CLL). Fludarabine phosphate was administered at a dose of 20 mg/m2/day intravenously for 5 days every 4 weeks as one course. Six courses as a maximum were repeated. The response rate was 38.5% (95% confidence intervals: 20.2% to 59.4%), with 1 complete remission and 9 partial remissions out of 26 treated patients. Major drug-related adverse reactions were fever, nausea, weakness, and paresthesia of the fingers; as a grade-3 reaction, varicella was also reported. Neutropenia and thrombocytopenia were observed as manifestations of hematologic toxicity. Clinical laboratory test results revealed abnormalities in hepatic function, including increased GPT, but none of these was rated grade 3 or 4.