2-CHLORODEOXYADENOSINE ACTIVITY IN PATIENTS WITH UNTREATED, INDOLENT NON-HODGKINS-LYMPHOMA

Based on the encouraging results of the use of 2-chlorodeoxyadenosine ([2-CdA], cladribine) in patients with advanced, low-grade lymphomas r esistant to conventional therapy and the acceptable toxicity profile e ncountered, we conducted a phase II trial of 2-CdA in patients with un treated indolent lymphomas. Twenty-eight patients with untreated low-g rade lymphomas were given 2-CdA at 0.1 mg/kg/d as a 7-day continuous i nfusion every 28 to 35 days. A total of 89 courses, median of three co urses per patient, of 2-CdA were administered. Seventeen men and 11 wo men with a median age of 58 years were treated. Fifteen patients had d iffuse small lymphocytic (8 with plasmacytoid features), 10 had follic ular small cleaved-cell, and there were single patients with monocytoi d B-cell, mantle cell and mucosa-associated lymphoid tissue (MALT) lym phoma histologies. All 28 patients were evaluable for toxicity and 26 were evaluable for response. Nine (35%) patients (4 with diffuse small lymphocytic, 3 with follicular small cleaved-cell, 1 with mantle cell , and 1 with MALT lymphoma) achieved a complete response, and 14 (54%) patients (8 with diffuse small lymphocytic, 5 with follicular small c leaved-cell, and 1 with monocytoid B-cell lymphoma) achieved a partial response, for an overall response rate of 88%. The median response du ration was 10 months (range, 3 to 44+). Myelosuppression was the princ ipal toxicity. Actuarial survival at 60 months from initial diagnosis was 60% (95% confidence interval, 35% to 82%) and at 48 months from tr eatment onset was 62% (95% confidence interval, 39% to 83%). These res ults establish the major activity of 2-CdA in patients with untreated indolent lymphoma, especially those with the diffuse small lymphocytic subtype. (C) 1995 by The American Society of Hematology.