FLUDARABINE IN RESISTANT OR RELAPSING B-CELL CHRONIC LYMPHOCYTIC-LEUKEMIA - THE SPANISH-GROUP EXPERIENCE

Fludarabine produces high response rates in patients with B-cell chron ic lymphocytic leukemia (CLL). Nevertheless, response to fludarabine o f patients with previously treated CLL varies from 17% to 74% (0% to 3 8% CR). In 68 patients with heavily pretreated and advanced CLL, an ov erall response rate to fludarabine of 28% (4% CR) was observed. Respon se correlated with sensitivity of the disease to previous treatments ( relapsing vs. refractory disease) (62% vs. 20%; p = 0.005) and, albeit not significantly, with the number of cycles of fludarabine (>3 vs. l ess than or equal to 3) that patients could receive (36% vs. 15%; p = NS). Responding patients had a longer survival (median, not reached) t han those not responding (median, 11 months) (p = 0.03). Severe toxici ty was observed in some cases. It is coneluded that fludarabine is a h ighly useful agent in CLL. However, in order to improve its effective ness and decrease its toxicity, fludarabine should be given as soon as a lack of response to front-line therapy is observed and before the d isease becomes completely resistant to therapy.