How it is administered

Cytarabine is administered as a sterile solution by intravenous (IV) infusion or injection, subcutaneous (under the skin) injection, or intrathecal (into the spinal fluid) injection. It is not effective if taken orally. The specific method and schedule of administration depend on the treatment plan and the type of blood cancer being treated. Cytarabine is available in various concentrations and vial sizes, both as single-dose and multi-dose vials, with or without preservatives.

How it works

Cytarabine is a chemotherapy medication that targets rapidly dividing cells, such as cancer cells found in blood cancers. It works by interfering with the DNA synthesis process, specifically during the S-phase of the cell cycle when DNA is being copied. Cytarabine is converted inside the body into an active form that inhibits DNA polymerase, an enzyme essential for DNA replication. This action prevents cancer cells from multiplying and leads to their death.

Because cytarabine primarily affects cells that are actively dividing, it is especially effective against certain types of leukemia and other blood cancers. However, it can also affect normal cells that divide quickly, such as those in the bone marrow, which leads to some of its side effects.

Who Should take it

Cytarabine is indicated for use in combination with other approved anti-cancer drugs for the induction of remission 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 administered intrathecally (into the spinal fluid) for the prevention and treatment of meningeal leukemia (leukemia involving the central nervous system).

The decision to use cytarabine is based on the type of leukemia or blood cancer, the patient’s overall health, and other factors determined by the healthcare team.

Who should not take it

Cytarabine should not be used in patients who have a known hypersensitivity or allergy to the drug. It should be used with caution in patients with pre-existing bone marrow suppression, as it can further lower blood cell counts and increase the risk of infection and bleeding.

Cytarabine can cause severe side effects, including bone marrow suppression, liver and kidney problems, and serious central nervous system, gastrointestinal, or lung toxicities, especially at high doses. It can also cause fetal harm, so it should not be used during pregnancy unless absolutely necessary. Women of childbearing potential should avoid becoming pregnant while on cytarabine.

Commonly used with

Cytarabine is most commonly used in combination with other chemotherapy agents, such as daunorubicin, idarubicin, or other drugs, depending on the specific leukemia protocol. These combinations are designed to increase the effectiveness of treatment and improve remission rates.

For central nervous system involvement, cytarabine may be combined with other medications like methotrexate and hydrocortisone for intrathecal administration.

Commonly tested with

Cytarabine is often tested in clinical trials in combination with other chemotherapy drugs, such as daunorubicin (as in the "7+3" regimen for AML), idarubicin, or etoposide. It is also tested with newer targeted therapies or immunotherapies in various research studies to improve outcomes in blood cancers.

In some protocols, cytarabine is used with other agents for high-dose or consolidation therapy, and its effects are monitored in combination with supportive care medications to manage side effects.