Last updated: October 6, 2014
Trade Names: Leukeran
Drug Class: Alkylating agent
Preparations: 2-mg tablet
Dose: 0.05–0.1 mg/kg/day; usual dose range, 4–6 mg/day, with dose adjusted according to WBC count
Indications: Immunosuppressant, occasionally used as an alternative for patients who cannot tolerate cyclophosphamide
Mechanism of Action: Alkylation and cross-linking of DNA strands interfering with DNA replication
Contraindications: Hypersensitivity, bone marrow suppression, BCG and live virus vaccines
Precautions: Teratogenic; can cause severe immunosuppression and cytopenias; carcinogenic; caution and dose reduction in hepatic and renal impairment
Monitoring: CBC, platelet count, serum uric acid, and LFTs frequently after initiation, then every 4 weeks
Pregnancy Risk: D
Common: Myelosuppression, rash, GI intolerance, oral ulceration
Less common: Confusion, seizures, sterility, pulmonary fibrosis, liver necrosis, drug fever, secondary malignancy, Stevens-Johnson syndrome, azoospermia, irreversible bone marrow failure
Immunosuppressants: Concurrent use of chlorambucil increases risk of myelosuppression and infection.
Patient Instructions: Avoid live virus vaccines. Avoid pregnancy. Regular monitoring is required.
Comments: When possible, azathioprine and methotrexate are used in preference to alkylating agents because the risk of secondary neoplasms is lower. Decrease in neutrophils and lymphocytes progresses even after drug is discontinued.
Clinical Pharmacology: Well absorbed; food decreases absorption 20%. Half- life 2 hours; hepatic metabolism and renal excretion of metabolites
Steinberg AD. Chlorambucil in the treatment of patients with immune-mediated rheumatic diseases. Arthritis Rheum 1993;36:325–328.PMID:8452576