Chlorambucil

Brand Names: Leukeran

Drug Class: Alkylating Drug

Overview

DESCRIPTION LEUKERAN (chlorambucil) was first synthesized by Everett et al. It is a bifunctional alkylating agent of the nitrogen mustard type that has been found active against selected human neoplastic diseases. Chlorambucil is known chemically as 4-[bis(2-chlorethyl)amino]benzenebutanoic acid and has the following structural formula: Chlorambucil hydrolyzes in water and has a pKa of 5.8.

Mechanism of Action

CLINICAL PHARMACOLOGY Mechanism of Action Chlorambucil, an aromatic nitrogen mustard derivative, is an alkylating agent. Chlorambucil interferes with DNA replication and induces cellular apoptosis via the accumulation of cytosolic p53 and subsequent activation of Bax, an apoptosis promoter. PHARMACOKINETICS In a study of 12 patients given single oral doses of 0.2 mg/kg of LEUKERAN, the mean dose-adjusted (±SD) plasma chlorambucil C max was 492 ± 160 ng/mL, the AUC was 883 ± 329 ng.h/mL, the mean elimination half-life (t½) was 1.3 ± 0.5 hours, and the T max was 0.83 ± 0.53 hours. For the major metabolite, phenylacetic acid mustard (PAAM), the mean dose-adjusted (± SD) plasma C max was 306 ± 73 ng/mL, the AUC was 1204 ± 285 ng.h/mL, mean t½ was 1.8 ± 0.4 hours, and the T max was 1.9 ± 0.

Indications

  • INDICATIONS AND USAGE LEUKERAN (chlorambucil) is indicated in the treatment of chronic lymphatic (lymphocytic) leukemia, malignant lymphomas including lymphosarcoma, giant follicular lymphoma, and Hodgkin’s disease. It is not curative in any of these disorders but may produce clinically useful palliation.

Common Doses

  • 0.2 mg
  • 10 mg
  • 0.1 mg
  • 6 mg

Dosage

DOSAGE AND ADMINISTRATION The usual oral dosage is 0.1 to 0.2 mg/kg body weight daily for 3 to 6 weeks as required. This usually amounts to 4 to 10 mg per day for the average patient. The entire daily dose may be given at one time. These dosages are for initiation of therapy or for short courses of treatment. The dosage must be carefully adjusted according to the response of the patient and must be reduced as soon as there is an abrupt fall in the white blood cell count. Patients with Hodgkin’s disease usually require 0.

Black Box Warning

WARNING LEUKERAN (chlorambucil) can severely suppress bone marrow function. Chlorambucil is a carcinogen in humans. Chlorambucil is probably mutagenic and teratogenic in humans. Chlorambucil produces human infertility (see WARNINGS and PRECAUTIONS).

Contraindications

  • CONTRAINDICATIONS Chlorambucil should not be used in patients whose disease has demonstrated a prior resistance to the agent. Patients who have demonstrated hypersensitivity to chlorambucil should not be given the drug. There may be cross-hypersensitivity (skin rash) between chlorambucil and other alkylating agents.

Side Effects

  • ADVERSE REACTIONS To report SUSPECTED ADVERSE REACTIONS, contact Waylis Therapeutics LLC Toll-Free at 1-888-514-4727 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. Hematologic The most common side effect is bone marrow suppression, anemia, leukopenia, neutropenia, thrombocytopenia, or pancytopenia. Although bone marrow suppression frequently occurs, it is usually reversible if the chlorambucil is withdrawn early enough. However, irreversible bone marrow failure has been reported.

Interactions

  • Drug Interactions There are no known drug/drug interactions with chlorambucil.