Phase II study of pentostatin in advanced T‐cell lymphoid malignancies

Abstract

BACKGROUND The goal of the current study was to assess the toxicity, safety, and efficacy of pentostatin in patients with T‐cell lymphoid malignancies. METHODS Patients were eligible if they had biopsy‐proven T‐cell lymphoma or leukemia and failure to respond to previous therapy or an expected complete response rate to conventional therapy of < 20%. Pentostatin was administered at an initial dose of 3.75 or 5.0 mg/m² by intravenous bolus daily over a consecutive 3‐day period every 3 weeks. RESULTS Forty‐two of 44 patients enrolled in the study were evaluable. The median age of the patients was 62 years (range, 38–86 years). Patients received a median of 3 previous therapies (range, 0–10 previous therapies). Of these patients, 32 (76%) had mycosis fungoides/Sézary syndrome and 10 patients (24%) had other T‐cell leukemias or lymphomas. The overall response rate was 54.8% (complete remission, 6 patients [14.3%]; partial remission, 17 patients [40.5%]). Durable responses were observed mainly in patients with Sézary syndrome or peripheral T‐cell lymphoma. The median follow‐up period for surviving patients was 20 months (range, 1–83+ months). The median duration of response was 4.3 months (range, 1–61 months). The most common toxicities were neutropenia, nausea, and CD4 suppression. A transient early ‘flare’ of disease was observed in some responders. CONCLUSIONS At these doses, pentostatin was reasonably well tolerated and is an effective drug for the treatment of T‐cell lymphomas. Cancer 2004;100:342–9. © 2003 American Cancer Society.