Cytarabine may be used alone or in combination with other chemotherapy drugs for the treatment of certain types of leukemia and related conditions. It is mainly indicated for induction of remission in patients with Acute Myeloid Leukemia (AML) in both adults and children. Cytarabine has also been used for remission induction in Acute Lymphoblastic Leukemia, Chronic Myeloid Leukemia, and Erythroleukemia. In addition, Cytarabine is used in the treatment and maintenance therapy of Meningeal Leukemia and other cancers affecting the meninges (the membranes surrounding the brain and spinal cord). Children with Non-Hodgkin Lymphoma may also benefit from combination chemotherapy regimens such as the LSA2L2 program, which includes Cytarabine.

Cytarabine is an antineoplastic (anticancer) drug belonging to the antimetabolite class. It is a synthetic pyrimidine nucleoside that is converted inside cells into its active form, cytarabine triphosphate. Although the exact mechanism is not completely understood, the active metabolite interferes with DNA synthesis by inhibiting the enzyme DNA polymerase. This prevents cancer cells from replicating their DNA and dividing. Cytarabine acts mainly during specific phases of the cell cycle, making it a cell cycle–specific chemotherapy drug. In addition to its anticancer properties, Cytarabine also has immunosuppressive effects and has demonstrated antiviral activity in laboratory studies.

Cytarabine Injection is not active orally. The schedule and method of administration varies with the program of therapy to be used. Cytarabine Injection may be given by intravenous infusion or injection, subcutaneously, or intrathecally (preservative free preparation only). In the induction therapy of acute non-lymphocytic leukemia, the usual cytarabine dose in combination with other anticancer drugs is 100 mg/m²/day by continuous IV infusion (1 to 7 Days) or 100 mg/m² IV every 12 hours (1 to 7 Days). The literature should be consulted for the current recommendations for use in acute lymphocytic leukemia.

Intrathecal Use in Meningeal Leukemia: Cytarabine injection has been used intrathecally in acute leukemia in doses ranging from 5 mg/m² to 75 mg/m² of body surface area.

Use in Children: Appropriate studies with cytarabine have not been performed in the paediatric population. However, paediatric specific problems that would limit the usefulness of this medication in children are not expected.

Use in the Elderly: Although studies with cytarabine have not been performed in the geriatric population, geriatric specific problems that would limit the usefulness of this medication in the elderly are not expected. Elderly patients are, however, more likely to have age related renal function impairment, which may require reduction of dosage in patients receiving cytarabine.

Cytarabine may reduce the effectiveness of certain medications such as Flucytosine, Digoxin, and Gentamicin. When Cytarabine is administered intrathecally together with other cytotoxic drugs, there may be an increased risk of neurotoxicity.

Cytarabine should not be used in patients who have previously shown hypersensitivity or allergic reactions to the drug.

The primary adverse effect of cytarabine is haematological toxicity. Myelosuppression typically presents as megaloblastosis, leukopenia, anaemia, reticulocytopenia, and thrombocytopenia. Leukopenia mainly results from granulocyte suppression, while lymphocytes are minimally affected. The severity of these effects depends on the dose and schedule of administration.

Haematologic toxicity is generally minimal after a single intravenous dose of cytarabine; however, myelosuppression occurs in most patients receiving daily IV injections or continuous IV infusions.

Nausea and vomiting may occur during cytarabine therapy and are more frequent and severe with rapid intravenous administration compared to continuous infusion.

Infections of viral, bacterial, fungal, or parasitic origin—ranging from mild to severe and potentially fatal—may be associated with cytarabine use, either alone or in combination with other immunosuppressive agents that impair cellular or humoral immunity.

Neurotoxicity following intrathecal administration of cytarabine has been linked to diluents containing preservatives; therefore, the use of preservative-free diluents is recommended.

A cytarabine syndrome has been reported, characterized by fever, myalgia, bone pain, malaise, maculopapular rash, conjunctivitis, and occasionally chest pain. A “flu-like” syndrome may also occur and, if severe, can be treated with corticosteroids. Anaphylactoid reactions have been reported.

This syndrome typically develops within 6 to 12 hours after drug administration. Corticosteroids have been shown to be effective in both prevention and treatment. If symptoms occur, continuation of cytarabine along with corticosteroid therapy should be considered.

Peripheral motor and sensory neuropathies have been reported in patients with adult non-lymphocytic leukaemia following consolidation therapy with high-dose cytarabine, daunorubicin, and asparaginase. Additionally, a syndrome of acute respiratory distress progressing rapidly to pulmonary oedema and marked cardiomegaly has been observed after high-dose cytarabine therapy for relapsed leukaemia, which may be fatal.

Cytarabine may cause serious fetal harm and has been shown to be teratogenic in animal studies. Therefore, it should not be used during pregnancy, especially in the first trimester or in women who may become pregnant. It is not known whether Cytarabine passes into human breast milk. Due to potential risks to the infant, breastfeeding should be avoided during treatment.

Caution is advised in patients with a history of drug-induced bone marrow suppression, as well as in those with renal or hepatic impairment. Special consideration should also be given during pregnancy and lactation.

Overdose of Cytarabine may cause severe bone marrow suppression, gastrointestinal toxicity, and persistent vomiting. Treatment should be stopped immediately and supportive care provided. Blood transfusion may be necessary in cases of severe bone marrow depression. Preventive measures such as Allopurinol therapy, adequate hydration, and urine alkalinization may be used to prevent hyperuricemia. Antiemetic therapy may be given to control nausea and vomiting.

Cytotoxic Chemotherapy

Store the vial in its original carton at 15°C–30°C. Protect from light. Do not refrigerate and keep out of the reach of children.