Common brand names

• Cytosar-U

How it is administered

Cytarabine is administered as a sterile solution for injection. It can be given in several ways:

• Intravenous (IV) infusion or injection: The most common method, either as a rapid injection or a slow infusion.
• Subcutaneous injection: Injected under the skin.
• Intrathecal injection: Injected directly into the spinal fluid (only preservative-free preparations are used for this route).

Cytarabine is not effective when taken by mouth, so it is always given by injection. The exact schedule and dose depend on the specific treatment plan and the type of leukemia being treated.

How it works

Cytarabine is a type of chemotherapy medication known as an antimetabolite. It works by interfering with the growth and division of cancer cells, particularly those that are rapidly dividing, such as leukemia cells.

Cytarabine is most active during the S-phase of the cell cycle, when DNA is being synthesized. It gets incorporated into the DNA of dividing cells and inhibits an enzyme called DNA polymerase, which is essential for DNA replication. This disruption prevents the cancer cells from multiplying and eventually leads to cell death.

Because cytarabine targets rapidly dividing cells, it also affects some normal cells in the body, which can lead to side effects. However, its main goal is to reduce the number of abnormal blood cells in conditions like leukemia.

Who should take it

Cytarabine is indicated for use in combination with other approved anti-cancer drugs for remission induction in acute non-lymphocytic leukemia (also known as acute myeloid leukemia, AML) in adults and children. It is also used in the treatment of acute lymphocytic leukemia (ALL) and the blast phase of chronic myelocytic leukemia (CML).

Additionally, cytarabine can be used intrathecally (injected into the spinal fluid) for the prevention and treatment of meningeal leukemia (leukemia involving the lining of the brain and spinal cord). While it is not specifically approved for chronic eosinophilic leukemia, it may be considered in certain cases of blood cancers as determined by your healthcare provider.

Who should not take it

Cytarabine should not be used in patients who are hypersensitive (allergic) to cytarabine or any of its components.

Cytarabine should be used with caution in patients who have pre-existing bone marrow suppression, liver or kidney dysfunction, or active infections, as these conditions can increase the risk of serious side effects. It is also not recommended for use in pregnant women unless the potential benefits outweigh the risks, as it can cause harm to the unborn baby. Breastfeeding is not recommended during treatment with cytarabine due to the potential for serious adverse reactions in nursing infants.

Commonly used with

Cytarabine is most often used in combination with other chemotherapy drugs to increase its effectiveness. Common combinations include:

• Daunorubicin (as in the combination regimen for AML)
• Other antineoplastic agents such as cyclophosphamide, vincristine, and prednisone

The specific combination depends on the type of leukemia and the treatment protocol being followed.

Commonly tested with

Cytarabine has been tested in combination with various other chemotherapy agents in clinical trials for leukemia and other blood cancers. These include:

• Daunorubicin (as in the standard "7+3" regimen for AML)
• Methotrexate and hydrocortisone (especially for intrathecal therapy)
• Asparaginase and etoposide (in some protocols for ALL)

Your healthcare team will determine the best combination based on your specific diagnosis and health needs.