Last reviewed 2026-04-20 · How we verify

Cytarabine

Cytarabine inhibits DNA polymerase and incorporates into DNA/RNA, killing cells in S-phase.

Cytarabine is an antimetabolite nucleoside analog indicated for remission induction in acute non-lymphocytic leukemia and treatment of acute lymphocytic leukemia and blast phase chronic myelocytic leukemia, with intrathecal use for meningeal leukemia prophylaxis and treatment. It demonstrates potent cytotoxicity through DNA polymerase inhibition and incorporation into DNA/RNA with cell cycle specificity for S-phase. Primary risks include extensive chromosomal damage, rapid metabolism limiting oral bioavailability, and potential drug interactions affecting digoxin and antibiotic efficacy. The drug remains a foundational component of acute leukemia treatment regimens with established clinical utility across multiple hematologic malignancies.

At a glance

Mechanism of action

Cytarabine exhibits cell phase specificity, primarily killing cells undergoing DNA synthesis (S-phase) and under certain conditions blocking progression from G1 phase to S-phase. Although the mechanism of action is not completely understood, cytarabine appears to act through inhibition of DNA polymerase. A limited but significant incorporation of cytarabine into both DNA and RNA has been reported, producing extensive chromosomal damage including chromatoid breaks. Cytarabine is metabolized by deoxycytidine kinase and other nucleotide kinases to the nucleotide triphosphate, an effective inhibitor of DNA polymerase, and is inactivated by pyrimidine nucleoside deaminase which converts it to the nontoxic uracil derivative. The balance of kinase and deaminase levels appears to be an important factor in determining cell sensitivity or resistance to cytarabine.

Approved indications

• Acute lymphoid leukemia
• Acute myeloid leukemia, disease
• Acute promyelocytic leukemia, FAB M3
• Lymphomatous meningitis
• Meningeal Leukemia

Boxed warnings

• WARNING Only physicians experienced in cancer chemotherapy should use cytarabine. For induction therapy patients should be treated in a facility with laboratory and supportive resources sufficient to monitor drug tolerance and protect and maintain a patient compromised by drug toxicity. The main toxic effect of cytarabine is bone marrow suppression with leukopenia, thrombocytopenia and anemia. Less serious toxicity includes nausea, vomiting, diarrhea and abdominal pain, oral ulceration, and hepatic dysfunction. The physician must judge possible benefit to the patient against known toxic effects of this drug in considering the advisability of therapy with cytarabine. Before making this judgment or beginning treatment, the physician should be familiar with the following text.

Common side effects

• Febrile Neutropenia
• Nausea
• Diarrhoea
• Constipation
• Oedema Peripheral
• Cough
• Headache
• Fatigue
• Epistaxis
• Decreased Appetite
• Vomiting
• Rash

Drug interactions

• Beta-acetyldigoxin
• Gentamicin
• Fluorocytosine

Key clinical trials

• Phase III Study of CPX-351 Versus 7+3 in Patients 60-75 Years Old With Untreated High Risk (Secondary) Acute Myeloid Leukemia (PHASE3)
• Testing the Addition of the Anti-cancer Drug Venetoclax and/or the Anti-cancer Immunotherapy Blinatumomab to the Usual Chemotherapy Treatment for Infants With Newly Diagnosed KMT2A-rearranged or KMT2A-non-rearranged Leukemia (PHASE2)
• A Study to Investigate Blinatumomab in Combination With Chemotherapy in Patients With Newly Diagnosed B-Lymphoblastic Leukemia (PHASE3)
• Pediatric-Inspired Regimen Combined With Venetoclax and Immunotherapy for Adult Ph-Negative Acute Lymphoblastic Leukemia (NA)
• Testing the Addition of Venetoclax or Gemtuzumab Ozogamicin (GO) to Usual Treatment Regimen (Cytarabine and Daunorubicin, "7+3") for Core Binding Factor Acute Myeloid Leukemia (CBF-AML) to Improve Response (A MyeloMATCH Treatment Trial) (PHASE2)
• Ibrutinib Before and After Stem Cell Transplant in Treating Patients With Relapsed or Refractory Diffuse Large B-cell Lymphoma (PHASE3)
• Standard-dose vs Intermediate-dose Cytarabine Induction in the Treatment of Acute Myeloid Leukemia With RUNX1-RUNX1T1 (PHASE3)
• Comparing Cytarabine + Daunorubicin Therapy Versus Cytarabine + Daunorubicin + Venetoclax Versus Venetoclax + Azacitidine in Younger Patients With Intermediate Risk AML (A MyeloMATCH Treatment Trial) (PHASE2)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Cytarabine CI brief — competitive landscape report
• Cytarabine updates RSS · CI watch RSS
• Nippon Shinyaku Co., Ltd. portfolio CI