Clinical efficacy of lenalidomide in patients with relapsed or refractory chronic lymphocytic leukemia: results of a phase II study

J Clin Oncol. 2006 Dec 1;24(34):5343-9. doi: 10.1200/JCO.2005.05.0401. Epub 2006 Nov 6.


Purpose: Patients with relapsed or refractory chronic lymphocytic leukemia (CLL) have profound immune defects and limited treatment options. Given the dramatic activity of lenalidomide in other B-cell malignancies and its pleotropic immunomodulatory effects, we conducted a phase II trial of this agent in CLL.

Patients and methods: Patients with relapsed or refractory B-cell CLL (B-CLL) were eligible if they required treatment as per the National Cancer Institute Working Group 1996 guidelines. Lenalidomide was administered orally at 25 mg on days 1 through 21 of a 28-day cycle. Response was assessed after each cycle. Patients were to continue treatment until disease progression, unacceptable toxicity, or complete remission. Rituximab was added to lenalidomide on disease progression.

Results: Forty-five patients were enrolled, with a median age of 64 years. Sixty-four percent of the patients had Rai stage III or IV disease, and 51% were refractory to fludarabine. The overall response rate was 47%, with 9% of the patients attaining a complete remission. Fatigue, thrombocytopenia, and neutropenia were the most common adverse effects noted in 83%, 78%, and 78% of the patients, respectively.

Conclusion: Lenalidomide is clinically active in patients with relapsed or refractory B-CLL. These findings are encouraging and warrant further investigation of this agent in the treatment of this disorder.

Publication types

  • Clinical Trial, Phase II
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / therapeutic use*
  • Fatigue / chemically induced
  • Female
  • Humans
  • Immunologic Factors / adverse effects
  • Immunologic Factors / therapeutic use*
  • Lenalidomide
  • Leukemia, Lymphocytic, Chronic, B-Cell / drug therapy*
  • Male
  • Middle Aged
  • Neoplasm Recurrence, Local / drug therapy
  • Neutropenia / chemically induced
  • Remission Induction
  • Thalidomide / adverse effects
  • Thalidomide / analogs & derivatives*
  • Thalidomide / therapeutic use
  • Thrombocytopenia / chemically induced


  • Antineoplastic Agents
  • Immunologic Factors
  • Thalidomide
  • Lenalidomide