Immunotoxin Therapy in Treating Patients With Hairy Cell Leukemia

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00021983
Recruitment Status : Completed
First Posted : December 12, 2003
Last Update Posted : April 29, 2015
Information provided by:
National Cancer Institute (NCI)

Brief Summary:

RATIONALE: An immunotoxin can locate cancer cells and kill them without harming normal cells. This may be an effective treatment for hairy cell leukemia.

PURPOSE: Phase I trial to study the effectiveness of BL22 immunotoxin in treating patients who have refractory or recurrent hairy cell leukemia.

Condition or disease Intervention/treatment Phase
Leukemia Biological: BL22 immunotoxin Phase 1

Detailed Description:


  • Assess the toxicity and therapeutic efficacy of recombinant BL22 immunotoxin in patients with refractory or recurrent CD22+ hairy cell leukemia.
  • Define the pharmacokinetics of this drug, including the terminal elimination serum half-life area under the curve and volume of distribution, in these patients.
  • Evaluate the immunogenicity of this drug in these patients.
  • Determine the effect of this drug on various components of the circulating cellular immune system in these patients.

OUTLINE: This is a dose-escalation study.

Patients receive recombinant BL22 immunotoxin IV over 30 minutes on days 1, 3, and 5. Treatment repeats at least every 42 days for up to 4 courses in the absence of disease progression and sufficient neutralizing antibodies.

Cohorts of 3-6 patients receive escalating doses of recombinant BL22 immunotoxin until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which no more than 1 of 6 patients experiences dose-limiting toxicity.

PROJECTED ACCRUAL: A maximum of 46 patients will be accrued for this study within 3 years.

Study Type : Interventional  (Clinical Trial)
Primary Purpose: Treatment
Official Title: Phase I Study of BL22, a Recombinant Immunotoxin for Treatment of CD22+ Leukemias and Lymphomas
Study Start Date : December 1998

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Leukemia
U.S. FDA Resources

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No


  • Histologically confirmed refractory or recurrent hairy cell leukemia

    • Relapsed after less than 2 years of complete remission after purine analog therapy
    • Must have at least one of the following indications for therapy:

      • Progressive or massive splenomegaly
      • Cytopenia defined by the following:

        • Absolute neutrophil count less than 1,000/mm^3 OR
        • Platelet count less than 100,000/mm^3 OR
        • Hemoglobin less than 12 g/dL
      • More than 20,000 hairy cells/mm^3
      • Symptomatic adenopathy
      • Constitutional symptoms including tumor-related fever or bone pain
  • Evidence of CD22 positivity by 1 of the following:

    • More than 15% of malignant cells from a site must react with anti-CD22 by immunohistochemistry
    • More than 30% of malignant cells from a site CD22+ by fluorescent-activated cell sorter
    • More than 400 CD22 sites/cell (average) on malignant cells as assessed by radiolabeled anti-CD22 binding
  • No CNS disease requiring treatment
  • No patients whose serum neutralizes BL22 immunotoxin in tissue culture, due to either antitoxin or antimouse-IgG antibodies

    • No patients whose serum neutralizes more than 75% of the activity of 1 microgram/mL of BL22 immunotoxin



  • 18 and over

Performance status:

  • Karnofsky 60-100%

Life expectancy:

  • More than 6 months


  • See Disease Characteristics
  • Pancytopenia due to disease allowed


  • ALT and AST less than 2.5 times upper limit of normal (ULN)
  • Bilirubin less than 1.5 times ULN


  • Creatinine no greater than 2.0 mg/dL


  • FEV1 at least 60% of predicted
  • DLCO at least 55% of predicted


  • HIV negative
  • Not pregnant or nursing
  • Negative pregnancy test
  • Fertile patients must use effective contraception


Biologic therapy:

  • Prior bone marrow transplantation allowed
  • At least 3 weeks since prior interferon for the malignancy
  • More than 3 months since prior monoclonal antibody therapy (e.g., rituximab)


  • See Disease Characteristics
  • At least 3 weeks since prior cytotoxic chemotherapy for the malignancy

Endocrine therapy:

  • Not specified


  • At least 3 weeks since prior whole body electron beam radiotherapy for the malignancy
  • Radiotherapy within the past 3 weeks allowed provided less than 10% of total bone marrow was treated and patient has measurable disease outside the radiation port


  • Not specified


  • At least 3 weeks since prior retinoids for the malignancy
  • At least 3 weeks since any other prior systemic therapy for the malignancy
  • No concurrent therapeutic warfarin

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00021983

United States, Maryland
Warren Grant Magnuson Clinical Center - NCI Clinical Studies Support
Bethesda, Maryland, United States, 20892-1182
Sponsors and Collaborators
National Cancer Institute (NCI)
Study Chair: Robert Kreitman, MD National Cancer Institute (NCI)

Publications of Results:
Other Publications: Identifier: NCT00021983     History of Changes
Obsolete Identifiers: NCT00001792
Other Study ID Numbers: CDR0000066835
First Posted: December 12, 2003    Key Record Dates
Last Update Posted: April 29, 2015
Last Verified: January 2006

Keywords provided by National Cancer Institute (NCI):
refractory hairy cell leukemia

Additional relevant MeSH terms:
Leukemia, Hairy Cell
Neoplasms by Histologic Type
Lymphoproliferative Disorders
Lymphatic Diseases
Immunoproliferative Disorders
Immune System Diseases
Immunologic Factors
Physiological Effects of Drugs