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: Directly into a vein, either as a slow infusion over several hours or as a rapid injection.
• Subcutaneous injection: Injected under the skin.
• Intrathecal injection: Injected into the fluid around the spinal cord (for certain types of leukemia affecting the central nervous system). Only preservative-free preparations are used for this route.

Cytarabine is not effective if taken by mouth (orally). The specific dosing schedule and method depend on the treatment plan designed by your healthcare provider.

How it works

Cytarabine is a type of chemotherapy medicine known as an antimetabolite. It works by interfering with the growth of cancer cells, specifically targeting cells that are actively dividing.

Cytarabine is most effective during the S-phase of the cell cycle, which is when cells are making new DNA. It gets incorporated into the DNA of the cancer cell, blocking the action of an enzyme called DNA polymerase. This prevents the cancer cell from making new DNA, which is essential for cell division and growth. As a result, the cancer cell cannot multiply and eventually dies.

Because cytarabine targets rapidly dividing cells, it also affects some healthy cells in the body that divide quickly, such as those in the bone marrow, digestive tract, and hair follicles. This is why side effects can occur.

Who Should take it

Cytarabine is used in combination with other approved anti-cancer drugs for the treatment of:

• Acute non-lymphocytic leukemia (also called acute myeloid leukemia or AML) in adults and children, including remission induction and maintenance.
• Acute lymphocytic leukemia (ALL).
• The blast phase of chronic myelocytic leukemia (CML).
• It is also used by intrathecal administration (injection into the spinal fluid) for the prevention and treatment of meningeal leukemia (leukemia involving the central nervous system).

For patients with Chronic Myelomonocytic Leukemia (CMML), cytarabine may be used, especially if the disease transforms into an acute leukemia phase. Your doctor will determine if cytarabine is appropriate based on your specific diagnosis and treatment goals.

Who should not take it

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

Cytarabine is a potent bone marrow suppressant, so it should be used with caution in patients with pre-existing bone marrow suppression. It should be started cautiously in these patients, and only under close medical supervision.

Cytarabine can cause fetal harm and should not be used during pregnancy unless absolutely necessary. Women of childbearing potential should avoid becoming pregnant while on cytarabine. If you are pregnant or planning to become pregnant, discuss this with your doctor.

Cytarabine should also be used with caution in patients with poor liver or kidney function, as these conditions can increase the risk of side effects. Your doctor will monitor your organ function closely during treatment.

Commonly used with

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

• Daunorubicin or other anthracyclines (for example, in the "7+3" regimen for AML)
• Cyclophosphamide
• Vincristine
• Prednisone
• Methotrexate (especially for central nervous system involvement)

The specific combination depends on the type of leukemia being treated and the treatment protocol chosen by your doctor.

Commonly tested with

Cytarabine has been tested in clinical trials with various other chemotherapy agents, including:

• Daunorubicin (as in the "7+3" regimen)
• Etoposide
• Asparaginase
• Methotrexate (especially for intrathecal therapy)
• Cyclophosphamide

These combinations are designed to improve treatment outcomes for different types of leukemia, including acute myeloid leukemia and chronic myelomonocytic leukemia when it progresses to an acute phase.