melphalan: clinical use

Prescribing considerations

• Restrict use to clinicians experienced with cytotoxic therapy.
• Assess marrow reserve, recent chemotherapy or radiotherapy, renal function, infection risk and concomitant nephrotoxins.
• Discuss fertility preservation before treatment where relevant.
• Assess thromboembolic risk when used with thalidomide- or lenalidomide-containing combinations.
• Balance expected benefit against mutagenicity and the risk of secondary haematological or solid malignancy.

Contraindications and cautions

• Hypersensitivity to melphalan or an excipient
• Breastfeeding

Monitoring

• Frequent full blood counts; counts may continue falling after treatment stops.
• Interrupt and reassess if leucocytes or platelets fall excessively.
• Monitor renal function closely in renal impairment or with nephrotoxic risk factors.
• Assess promptly for infection, bleeding, pulmonary toxicity, hepatic dysfunction and thromboembolism.
• Maintain longer-term vigilance for secondary malignancy.

Clinical pharmacology

A bifunctional alkylating nitrogen mustard that cross-links DNA through guanine residues. Oral absorption is highly variable, is reduced by food, and clearance may decrease with renal impairment.

Formulation and product differences

• The selected product is a refrigerated, film-coated oral tablet.
• Intact tablets may be handled, but they must not be divided; damaged tablets require cytotoxic-handling precautions.
• Oral absorption is variable; intravenous melphalan is a separate formulation used when predictable exposure is required.

Tablet

Route: Oral

Strengths: 2 mg