Major activity of cladribine in patients with de novo B-cell prolymphocytic leukemia

J Clin Oncol. 1997 Jan;15(1):37-43. doi: 10.1200/JCO.1997.15.1.37.


Purpose: De novo B-cell prolymphocytic leukemia (B-PLL) is a distinct clinicopathologic entity usually characterized by marked lymphocytosis, massive splenomegaly, an aggressive course, and refractoriness to therapy. Cladribine (2-chlorodeoxyadenosine [2-CdA]; Ortho Biotech, Raritan, NJ) is a newer purine analog with potent activity against indolent lymphoproliferative disorders.

Patients and methods: We treated eight patients with cladribine 0.1 mg/kg/d for 7 days by continuous infusion or 0.14 mg/kg/d over 2 hours for 5 days, every 28 to 35 days, for a median of three courses (range, two to five). There were five men and three women, with a median age of 62 years and a median pretreatment duration of 6 months; four patients were previously untreated.

Results: All eight patients were assessable: five achieved a complete response with a median response duration of 14 months (range, 1+ to 55+), and three achieved a partial response with a median duration of 3 months (range, 1 to 3). Of four patients who achieved a complete response and in whom a peripheral-blood immunophenotypic analysis was performed, two had no circulating B-PLL cells and one had no residual disease on Southern blot analysis. Myelosuppression and infection were the major toxicities: three patients developed grade 3 or 4 myelosuppression, four had bacterial infections, and two had herpes zoster infections.

Conclusion: In this small study of patients with de novo B-PLL, cladribine was an active agent that induced a high overall and complete response rate. These results require confirmation in larger numbers of B-PLL patients.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / therapeutic use*
  • Cladribine / adverse effects
  • Cladribine / therapeutic use*
  • Drug Administration Schedule
  • Female
  • Humans
  • Leukemia, Prolymphocytic / drug therapy*
  • Leukemia, Prolymphocytic / microbiology
  • Leukemia, Prolymphocytic / pathology
  • Male
  • Middle Aged
  • Neoplasm Staging


  • Antineoplastic Agents
  • Cladribine