Common brand names

• Onureg
• Vidaza

How it is administered

Azacitidine is administered as an injection. It is available as a sterile powder that must be reconstituted for use. It can be given in two ways:

• Subcutaneous injection: Injected under the skin, usually in the thigh, abdomen, or upper arm. The injection site should be rotated with each dose.
• Intravenous infusion: Administered through a vein, typically over 10 to 40 minutes.

The typical starting dose for adults is 75 mg/m² daily for 7 days, repeated every 4 weeks. Your healthcare provider will determine the exact dosing and schedule for you. Azacitidine is not interchangeable with oral azacitidine products, and the dosing regimens are different.

How it works

Azacitidine is a type of chemotherapy called a nucleoside metabolic inhibitor. It works by interfering with the DNA in abnormal blood cells. Specifically, azacitidine is a pyrimidine nucleoside analog of cytidine. It is believed to work in two main ways:

1. Hypomethylation of DNA: Azacitidine can reduce the methylation (a chemical modification) of DNA. This hypomethylation may help restore the normal function of genes that control how blood cells grow and mature, which can be disrupted in blood cancers.

2. Direct cytotoxicity: Azacitidine is toxic to abnormal, rapidly dividing blood cells in the bone marrow. By targeting these cells, it helps reduce the number of abnormal cells and allows healthier blood cells to grow.

Non-dividing (resting) cells are less affected by azacitidine, making it more selective for cancerous or abnormal cells that are actively dividing.

Who should take it

Azacitidine is indicated for adults with certain types of myelodysplastic syndromes (MDS), which are a group of blood cancers that affect the bone marrow and blood cell production. These include:

• Refractory anemia (RA)
• Refractory anemia with ringed sideroblasts (RARS), especially if accompanied by low white blood cells or platelets, or if transfusions are needed
• Refractory anemia with excess blasts (RAEB)
• Refractory anemia with excess blasts in transformation (RAEB-T)
• Chronic myelomonocytic leukemia (CMMoL)

While not specifically approved for large granular lymphocytic leukemia (LGL), azacitidine is used in related blood cancers and may be considered in certain situations as determined by your doctor.

Who should not take it

You should not take azacitidine if you:

• Have advanced malignant hepatic (liver) tumors
• Are allergic to azacitidine or mannitol (an ingredient in the formulation)

Caution is needed if you have severe pre-existing liver or kidney problems, as you may be at higher risk for side effects. Azacitidine can cause harm to unborn babies, so it should not be used during pregnancy. Women of childbearing age and men with partners who could become pregnant should use effective contraception during and after treatment (6 months for women, 3 months for men).

Commonly used with

Azacitidine is often used as a single agent for treating myelodysplastic syndromes, but it may be combined with supportive care measures such as:

• Blood transfusions (red cells or platelets)
• Antibiotics for infections
• Medications to manage side effects (such as anti-nausea drugs)

It is not typically combined with other chemotherapy agents for MDS, but your doctor may adjust your treatment plan based on your specific needs.

Commonly tested with

Azacitidine has been tested in clinical trials against best supportive care, low-dose cytarabine, and combination chemotherapy regimens (such as cytarabine with anthracyclines) in patients with myelodysplastic syndromes. It is also studied in combination with other supportive therapies, but not usually with other chemotherapy drugs for initial treatment of MDS.