Melphalan, sold under the brand name Alkeran among others, is a chemotherapy medication used to treat multiple myeloma, ovarian cancer, melanoma, and AL amyloidosis. It is taken by mouth or by injection into a vein. Common side effects include nausea and bone marrow suppression. Other severe side effects may include anaphylaxis and the development of other cancers. Use during pregnancy may result in harm to the fetus. Melphalan belongs to the class of nitrogen mustard alkylating agents. It works by interfering with the creation of DNA and RNA. Melphalan was approved for medical use in the United States in 1964. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. Medical uses It is used to treat multiple myeloma, ovarian cancer, AL amyloidosis, and occasionally malignant melanoma. The agent was first investigated as a possible drug for use in melanoma, it was not found to be effective. In 2016, it was approved in the U.S. for: use as a high-dose conditioning treatment prior to hematopoietic progenitor (stem) cell transplantation in multiple myeloma (MM) patients the palliative treatment of MM patients for whom oral therapy is not appropriate Melphalan is used to treat ocular retinoblastoma, a pediatric solid tumor. This is accomplished via transarterial catheter based slow pulsed infusion into the ophthalmic artery. Side effects Common side effects include: Nausea Bone marrow suppression, including Decreased white blood cell count causing increased risk of infection Decreased platelet count causing increased risk of bleeding Less common side effects include: Severe allergic reactions Pulmonary fibrosis (scarring of lung tissue) including fatal outcomes (usually only with prolonged use) Hair loss Interstitial pneumonitis Rash Itching Irreversible bone marrow failure due to melphalan not being withdrawn early enough Cardiac arrest Mechanism of action Melphalan chemically alters the DNA nucleotide guanine through alkylation, and causes linkages between strands of DNA. This chemical alteration inhibits DNA synthesis and RNA synthesis, functions necessary for cells to survive. These changes cause cytotoxicity in both dividing and non-dividing tumor cells. Tumor cells spend less time in resting phases than normal cells so at any given time, they are more likely to be metabolically active than most normal host cells. The rationale behind incorporating an alkylating function in a molecule resembling a primary cellular metabolite was to get a greater safety margin by fooling tumor cells into taking up the toxin preferentially. Synthesis 4-Nitro-L-phenylalanine (1)