What it's for (Indications)
- Melphalan is an alkylating agent indicated for the palliative treatment of patients with multiple myeloma.
- It is often used in combination with corticosteroids like prednisone for standard-dose regimens, or as a high-dose conditioning regimen prior to autologous hematopoietic stem cell transplantation (HSCT) for patients with multiple myeloma.
- Additionally, melphalan is indicated for the palliative treatment of patients with epithelial ovarian cancer.
- Its use may extend to other neoplastic diseases, such as neuroblastoma or specific lymphomas, typically in highly specialized, high-dose protocols as part of a conditioning regimen.
- The decision to use melphalan is based on a careful assessment of the disease stage, patient's overall health, and potential benefits versus significant risks associated with this potent chemotherapy agent.
Dosage Information
| Type | Guideline |
|---|---|
| Standard | Melphalan dosage is highly individualized and depends on the specific indication, patient's body surface area (BSA) or weight, renal function, and whether it is administered as a standard or high-dose regimen. For standard-dose multiple myeloma, typical oral regimens might involve 6 mg/m² daily for 4-7 days every 4-6 weeks, often combined with prednisone. For high-dose conditioning prior to HSCT, intravenous melphalan doses commonly range from 100-200 mg/m² administered as a single dose or divided over 2-3 days. Dosage adjustments are crucial for patients with renal impairment or significant myelosuppression. Close monitoring of hematologic parameters (complete blood counts with differential) is essential throughout treatment to guide dose modifications and mitigate severe toxicity. Administration must be supervised by a physician experienced in chemotherapy. |
Safety & Warnings
Common Side Effects
- Melphalan is associated with a range of dose-dependent and potentially severe side effects.
- The most prominent and dose-limiting toxicity is severe myelosuppression, leading to leukopenia, thrombocytopenia, and anemia, which can result in life-threatening infections and hemorrhage.
- Gastrointestinal toxicities are common and include severe nausea, vomiting, mucositis (stomatitis), diarrhea, and abdominal pain.
- Other significant adverse effects can include alopecia (hair loss), skin rash, pruritus, and occasional skin hyperpigmentation.
- Less common but serious side effects involve pulmonary toxicity (e.
- g.
- , interstitial pneumonitis, pulmonary fibrosis), hepatic dysfunction (transient elevations in liver enzymes), and renal impairment.
- Long-term use carries a substantial risk of secondary malignancies, particularly acute non-lymphocytic leukemia and myelodysplastic syndrome.
- Reproductive toxicity, including infertility and amenorrhea, is also a concern for both male and female patients.
Serious Warnings
- Black Box Warning: BLACK BOX WARNING: **MYELOSUPPRESSION:** Melphalan causes severe and prolonged myelosuppression, leading to significant leukopenia, thrombocytopenia, and anemia. This profound bone marrow depression can result in life-threatening infections and hemorrhage. Complete blood counts with differential must be monitored frequently, and dosage adjustments, including dose reductions or temporary cessation of treatment, are often required based on hematologic parameters and recovery. Patients should be informed of the signs and symptoms of myelosuppression and advised to seek immediate medical attention if they occur. **SECONDARY MALIGNANCIES:** Melphalan is a human carcinogen and leukemogen. There is an increased risk of developing secondary primary malignancies, particularly acute non-lymphocytic leukemia (ANLL) and myelodysplastic syndrome (MDS), several years after treatment with melphalan. The risk of these secondary cancers must be weighed against the potential therapeutic benefits of melphalan, especially in non-life-threatening conditions. **EMBRYOFETAL TOXICITY:** Melphalan can cause severe fetal harm when administered to a pregnant woman. Animal studies demonstrate teratogenic, embryotoxic, and mutagenic effects. Advise pregnant women of the potential risk to the fetus. Females of reproductive potential must use effective contraception during treatment with melphalan and for at least 6 months following the last dose. Males with female partners of reproductive potential must use effective contraception during treatment and for at least 3 months after the last dose.
- Melphalan carries several serious warnings due to its potent cytotoxic nature.
- Profound and prolonged myelosuppression, primarily leukopenia and thrombocytopenia, is expected and requires diligent monitoring of complete blood counts; dose adjustments or treatment interruptions may be necessary.
- Melphalan is a known human carcinogen, increasing the risk of secondary malignancies, notably acute non-lymphocytic leukemia and myelodysplastic syndrome, years after treatment.
- Hypersensitivity reactions, including anaphylaxis, have been reported, requiring immediate discontinuation and appropriate medical management.
- It is embryotoxic, teratogenic, and mutagenic; therefore, effective contraception is mandatory for patients of reproductive potential during and after treatment.
- Renal impairment necessitates careful dose modification to avoid increased toxicity.
- Pulmonary toxicity, though rare, can be severe, including interstitial pneumonitis and fibrosis.
- Extravasation during intravenous administration can cause severe local tissue damage.
How it Works (Mechanism of Action)
Melphalan is an alkylating agent of the nitrogen mustard type, a well-established class of cytotoxic chemotherapy drugs. Its primary mechanism of action involves the formation of covalent bonds with nuclear DNA, specifically targeting guanine bases. This alkylation leads to intra-strand and inter-strand cross-linking of DNA molecules. These cross-links impede essential cellular processes such as DNA replication and transcription, ultimately inhibiting protein synthesis and RNA synthesis. The cumulative effect of these molecular disruptions is profound damage to the DNA structure, triggering cell cycle arrest and inducing apoptosis in rapidly dividing cancer cells. Melphalan's action is largely cell cycle non-specific, meaning it can kill cells in various phases of the cell cycle, contributing to its broad cytotoxic efficacy against neoplastic cells.
Commercial Brands (Alternatives)
No other brands found for this formula.