Low-dose oral fludarabine plus cyclophosphamide in elderly patients with chronic lymphoproliferative disorders.

A synergistic effect of fludarabine (FLU) and cyclophosphamide (CY) has been extensively demonstrated in the treatment of chronic lymphoproliferative disorders (CLD), although a high incidence of severe neutropenia and infectious complications, particularly in elderly patients, have been reported. Based on a previous clinical experience in elderly CLD patients treated with a combination of low-dose intravenous (i.v.) FLU and CY in whom we obtained good response rates and negligible toxicity, we tested efficacy and safety of the new oral formulation of FLU combined with CY at low doses. A total of 28 elderly patients with relapsed/refractory or untreated CLD were treated with oral FLU and CY (25 and 150 mg/m2 respectively, both for 4 days every 4 weeks). The treatment design consisted in four consecutive courses and the median value of courses per patient was 3. Overall, 25 out of 28 evaluable patients were responsive to the treatment (six CR and 19 PR; ORR 89\%), while the remaining three patients did not show any appreciable response (two progressive and one stable disease). Hematological toxicity was low in the majority of patients (grade 2-3 neutropenia/anemia in 8/28 cases); however, two fatal infections occurred and one additional patient died because of disease progression. Extra-hematological toxicity was generally mild. This preliminary report suggests that oral combination of FLU and CY at low dose is effective as the i.v. formulation and standard doses, since it may induce rapid responses in about 90\% of elderly patients with CLD, with an acceptable toxicity.