Aims: The study was carried out to investigate the efficacy and toxicity of fludarabine phosphate in the treatment of B-cell chronic lymphocytic leukemia (B-CLL) in previously treated patients.
Methods: Sixteen patients, 11 males and 5 females, 9 in stage B and 7 in stage C, according to the Binet Staging System, were treated with a maximum of 6 cycles of fludarabine (25 mg/m2) for 5 days, every 4 weeks. All patients had been pretreated, 10 were refractory to standard regimens, 5 were in relapse, and 1 patient was in partial remission.
Results: Thirteen patients were judged suitable for evaluation. Overall 9 patients were responsive to treatment; 4 complete and 5 partial responses were observed. Of the 4 patients in complete remission, 3 were alive at 6, 10 and 13 months, respectively, from the beginning of treatment. One patient died after 11 months for acute graft-versus-host disease after allogenic bone marrow transplantation by an HLA sibling donor. Two of the 5 patients in partial remission were alive at 7 and 17 months, respectively, and the other 3 died (2 of disease reexpansion after 14 and 16 months and 1 of septic shock following pneumonia). Four patients were not responsive to treatment: 1 died from disease progression after 8 months from the beginning of therapy, 1 from cardiac failure after 9 months, 1 from septic shock following meningitis, and 1 was alive after 7 months of follow-up. Treatment was well tolerated, with nausea and vomiting in only one patient. We observed two episodes of pneumonitis, without any evidence of the responsible agent, a tumor lysis syndrome with acute renal failure, a recurrence of autoimmune thrombocytopenia, and a Coombs-positive hemolytic anemia.
Conclusions: Fludarabine phosphate is effective in the treatment of patients with advanced B-CLL, even in those refractory to multiple chemotherapy regimens.