Cladribine in the treatment of advanced relapsed or refractory low and intermediate grade non-Hodgkin's lymphoma

Cladribine (2-chlorodeoxyadenosine) is a purine nucleoside analog with cytotoxic activity against both resting and proliferating cells. Clinical studies with cladribine have reported antitumor activity against various hematologic malignancies.

The authors studied responses to cladribine among patients with low and intermediate grade non-Hodgkin's lymphoma that had been refractory to or relapsed after prior chemotherapy. Cladribine was given intravenously over 2 hours at a dose of 0.14 mg/kg daily for 5 consecutive days, repeated every 4 weeks.

Twenty-eight patients (16 males, 12 females) with a median age of 58 years (range, 41-75 years) were accrued. Twenty-three patients had low grade and 5 had intermediate grade lymphoma. Stage IV disease was present in 22 (79%), and 17 (61%) had systemic B-symptoms. The majority (57%) had received 2 or more prior chemotherapy regimens (median, 2; range, 1-5); 6 had had prior fludarabine therapy. Major responses were documented in 32% (9 of 28 patients), with 4 complete remissions (CR) and 5 partial remissions (PR) after a median of 4 cycles (range, 1-9). One CR occurred in one patient with intermediate grade diffuse large cell lymphoma, and three of six patients who had had prior fludarabine therapy experienced CR or PR with cladribine. Severe hematologic toxicities included reversible neutropenia, protracted thrombocytopenia, and lymphopenia. Other reported adverse effects included mild-to-moderate fatigue, nausea, and diarrhea.

Cladribine is an active single agent in the treatment of patients with refractory or relapsed advanced stage indolent lymphoma, with major responses in one third of patients.