Rituximab therapy of patients with B-cell chronic lymphocytic leukemia

Blood. 2001 Sep 1;98(5):1326-31. doi: 10.1182/blood.v98.5.1326.


Rituximab (IDEC-C2B8) is a chimeric antibody that binds to the B-cell surface antigen CD20. Rituximab has significant activity in follicular non-Hodgkin lymphomas. Much less is known about the effects in chronic lymphocytic leukemia (CLL). We have initiated a phase II trial to evaluate the efficacy and safety of rituximab in patients with CD20+ pretreated CLL. To avoid the rituximab-associated toxicity, we restricted the tumor cell load, as measured by the number of circulating lymphocytes and the spleen size, in the first 2 cohorts of patients included in the study. Patients received 4 intravenous infusions of 375 mg/m2 once a week over a period of 1 month. Of the 28 patients evaluable for response, 7 patients showed a partial remission (National Cancer Institute criteria) lasting for a median of 20 weeks, with 1 patient still in remission after 71 weeks. Based on lymphocyte counts only, we found at least a 50% reduction of lymphocyte counts lasting for at least 4 weeks in 13 (45%) of 29 patients. Fifteen patients from 3 institutions were monitored for the immunophenotype profile of lymphocyte subsets. The number of CD5+CD20+ cells decreased significantly and remained low until day 28 after therapy. T-cell counts were not affected. With the exception of one rituximab-related death, adverse events in the remaining patients were mild. The results suggest that rituximab has clinical activity in pretreated patients with B-CLL. Toxicity is tolerable. Response duration after withdrawal of rituximab is rather short. Therefore, other modes of application and the combination with other agents need to be tested.

Publication types

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

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antibodies, Monoclonal / adverse effects
  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / therapeutic use*
  • Antibodies, Monoclonal, Murine-Derived
  • Antigens, CD20 / immunology*
  • Antigens, Neoplasm / immunology*
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / immunology
  • Antineoplastic Agents / therapeutic use*
  • Cardiovascular Diseases / chemically induced
  • Disease Progression
  • Female
  • Fever / chemically induced
  • Humans
  • Immunophenotyping
  • Immunotherapy*
  • Infusions, Intravenous
  • Life Tables
  • Lymphocyte Count
  • Lymphoma, Follicular / immunology
  • Lymphoma, Follicular / mortality
  • Lymphoma, Follicular / therapy*
  • Male
  • Middle Aged
  • Multiple Organ Failure / chemically induced
  • Remission Induction
  • Rituximab
  • Survival Analysis


  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Murine-Derived
  • Antigens, CD20
  • Antigens, Neoplasm
  • Antineoplastic Agents
  • Rituximab