Comparison of fludarabine, cyclophosphamide/doxorubicin/prednisone, and cyclophosphamide/doxorubicin/vincristine/prednisone in advanced forms of chronic lymphocytic leukemia: preliminary results of a controlled clinical trial. The French Cooperative Group on Chronic Lymphocytic Leukemia.

In a multicenter clinical trial conducted by the French Cooperative Group on Chronic Lymphocytic Leukemia (CLL) between June 1, 1990, and October 1, 1992, 183 patients with stage B CLL and 79 patients with stage C CLL were randomized to receive either cyclophosphamide/doxorubicin/prednisone (CAP) (71 stage B patients and 25 stage C patients), or cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) (56 stage B patients and 27 stage C patients), or fludarabine (FDB) (56 stage B patients and 27 stage C patients). The mean follow-up was 14 months (standard deviation, 7 months). At the 6-month follow-up examination, the results suggested that FDB was more effective than CAP and CHOP in patients with stage B disease (n = 183), with 19% of FDB-treated patients achieving "clinical and hematological remission" (CR) compared with 11% of the CHOP-treated patients and 7% of the CAP-treated patients (P = .08; 6 degrees of freedom; chi-squared test). The rates of partial remission (PR) and overall response (CR + PR) were, respectively, 75% and 94% for the FDB-treated patients, 64% and 75% for the CHOP-treated patients, and 65% and 72% for the CAP-treated patients. However, in patients with stage C CLL (n = 77) at entry to the study, the remission status at 6 months showed slightly greater improvement in the CAP-treated group (n = 25), in which 84% of patients achieved remission (CR + PR) compared with 64% of patients in the FDB-treated group (n = 27) and 63% of patients in the CHOP-treated group (n = 27). Further analysis of the study data may help to clarify the significance of these findings and to determine whether FDB improves survival in patients with advanced CLL.