CYTARABINE- cytarabine injection, solution
APP Pharmaceuticals, LLC
Rx only
For Intravenous, Intrathecal and Subcutaneous Use Only
BOXED WARNING
Only physicians experienced in cancer chemotherapy should use Cytarabine Injection.
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 injection 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 Injection. Before making this judgment or beginning treatment, the physician should be familiar with the following text.
DESCRIPTION
Cytarabine Injection, an antineoplastic, is a sterile solution of cytarabine for intravenous, intrathecal or subcutaneous administration. Each mL contains 100 mg cytarabine USP, in 2 g /20 mL (100 mg/mL) single dose vial and the following inactive ingredients: water for injection q.s. When necessary the pH is adjusted with hydrochloric acid and/or sodium hydroxide to a pH of 7.7.
Cytarabine is chemically 1-?-D-Arabinofuranosylcytosine. The structural formula is:
cytarabine-structure
C9 H13 N3 O5 M.W. 243.22
Cytarabine is an odorless, white to off-white crystalline powder which is freely soluble in water and slightly soluble in alcohol and in chloroform.
CLINICAL PHARMACOLOGY
Cell Culture Studies
Cytarabine is cytotoxic to a wide variety of proliferating mammalian cells in culture. It exhibits cell phase specificity, primarily killing cells undergoing DNA synthesis (S-phase) and under certain conditions blocking the progression of cells from the G1 phase to the S-phase. Although the mechanism of action is not completely understood, it appears that cytarabine acts through the inhibition of DNA polymerase. A limited, but significant, incorporation of cytarabine into both DNA and RNA has also been reported. Extensive chromosomal damage, including chromatoid breaks, have been produced by cytarabine and malignant transformation of rodent cells in culture has been reported. Deoxycytidine prevents or delays (but does not reverse) the cytotoxic activity.
Cellular Resistance and Sensitivity
Cytarabine is metabolized by deoxycytidine kinase and other nucleotide kinases to the nucleotide triphosphate, an effective inhibitor of DNA polymerase; it is inactivated by a pyrimidine nucleoside deaminase, which converts it to the non-toxic uracil derivative. It appears that the balance of kinase and deaminase levels may be an important factor in determining sensitivity or resistance of the cell to cytarabine.
