IN-VITRO DRUG-INDUCED CYTOTOXICITY PREDICTS CLINICAL-RESPONSE TO FLUDARABINE IN B-CELL CHRONIC LYMPHOCYTIC-LEUKEMIA

We investigated the possible value of an in vitro drug-induced cytotox icity assay in predicting clinical response to fludarabine (FAMP) in c hronic lymphocytic leukaemia (CLL). The median FAMP-LD50 values for ca ses designated as complete response (CR), partial response (PR), no re sponse (NR) and progressive disease (PD) were 1.43, 2.05, 24.5 and 77. 9 mu g/ml, respectively (P=0.013), A significant lower mean FAMP-LD50 value was observed in the in vivo responding cases as compared to non- responding ones (3.0 +/- 0.82 SEM v 42.3 +/- 12.6 SEM. P=0.001). Only FAMP-LD50 less than or equal to 2.5 mu g/ml and more than four FAMP co urses significantly influenced the response rate in univariate and mul tivariate analyses, The MTT assay may be of value in predicting clinic al response to FAMP in CLL patients.