Cytarabine - Cytosar®
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|NS, D5W, D5NS, LR
| Chemical Stability of Infusion Solutions:
Chemical stability studies were performed by a stability indicating HPLC assay on Cytarabine Injection in infusion solutions. These studies showed that when Cytarabine Injection was diluted with Water for Injection, 5% Dextrose Injection or Sodium Chloride Injection, in both glass and plastic infusion bags, 97-100% of the cytarabine was present after 8 days storage at room temperature.1
CYTARABINE injection, powder, lyophilized, for solution:
IV Infusion volumes: 100 to 1000 mL NS or D5W.
|Stability / Miscellaneous
A Pharmacy Bulk Package is a container of a sterile preparation for parenteral use that contains many single doses. The contents are intended for use in a pharmacy admixture program and are restricted to the preparation of admixtures for intravenous infusion.
Each mL contains 20 mg Cytarabine, USP and the following inactive ingredients: sodium chloride 0.68% and Water for Injection q.s. When necessary, the pH is adjusted with hydrochloric acid and/or sodium hydroxide to a target pH of 7.4. Each vial contains approximately 5.82 mEq sodium.
Cytarabine is an odorless, white to off-white, crystalline powder which is freely soluble in water and slightly soluble in alcohol and in chloroform.
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 nontoxic 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.
Human Pharmacology: Cytarabine is rapidly metabolized and is not effective orally; less than 20 percent of the orally administered dose is absorbed from the gastrointestinal tract.
Following rapid intravenous injection of cytarabine, labeled with tritium, the disappearance from plasma is biphasic. There is an initial distributive phase with a half-life of about 10 minutes, followed by a second elimination phase with a half-life of about 1 to 3 hours. After the distributive phase, more than 80 percent of plasma radioactivity can be accounted for by the inactive metabolite 1-β-D-arabinofuranosyluracil (ara-U). Within 24 hours about 80 percent of the administered radioactivity can be recovered in the urine, approximately 90 percent of which is excreted as ara-U.
Relatively constant plasma levels can be achieved by continuous intravenous infusion.
After subcutaneous or intramuscular administration of cytarabine labeled with tritium, peak-plasma levels of radioactivity are achieved about 20 to 60 minutes after injection and are considerably lower than those after intravenous administration.
Cerebrospinal fluid levels of cytarabine are low in comparison to plasma levels after single intravenous injection. However, in one patient in whom cerebrospinal levels were examined after 2 hours of constant intravenous infusion, levels approached 40 percent of the steady state plasma level. With intrathecal administration, levels of cytarabine in the cerebrospinal fluid declined with a first order half-life of about 2 hours. Because cerebrospinal fluid levels of deaminase are low, little conversion to ara-U was observed.
Immunosuppressive Action: Cytarabine is capable of obliterating immune responses in man during administration with little or no accompanying toxicity. Suppression of antibody responses to E. coli-VI antigen and tetanus toxoid have been demonstrated. This suppression was obtained during both primary and secondary antibody responses.
Cytarabine also suppressed the development of cell-mediated responses such as delayed hypersensitivity skin reaction to dinitrochlorobenzene. However, it had no effect on already established delayed hypersensitivity reactions.
Following 5-day courses of intensive therapy with cytarabine, the immune response was suppressed, as indicated by the following parameters: macrophage ingress into skin windows; circulating antibody response following primary antigenic stimulation; lymphocyte blastogenesis with phytohemagglutinin. A few days after termination of therapy there was a rapid return to normal.
INDICATIONS AND USAGE
DOSAGE AND ADMINISTRATION
Cytarabine Injection is not active orally. The schedule and method of administration varies with the program of therapy to be used. While Cytarabine Injection may be given by intravenous infusion or injection, or subcutaneously or intrathecally, THE PURPOSE OF THE PHARMACY BULK PACKAGE IS FOR THE PREPARATION OF INTRAVENOUS INFUSIONS. Thrombophlebitis has occurred at the site of drug injection or infusion in some patients, and rarely patients have noted pain and inflammation at subcutaneous injection sites. In most instances, however, the drug has been well tolerated.
Patients can tolerate higher total doses when they receive the drug by rapid intravenous injection as compared with slow infusion. This phenomenon is related to the drug’s rapid inactivation and brief exposure of susceptible normal and neoplastic cells to significant levels after rapid injection. Normal and neoplastic cells seem to respond in somewhat parallel fashion to these different modes of administration and no clear-cut clinical advantage has been demonstrated for either.
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 (Days 1-7) or 100 mg/m2 IV every 12 hours (Days 1-7).
The literature should be consulted for the current recommendations for use in acute lymphocytic leukemia.
Intrathecal Use in Meningeal Leukemia:
If used intrathecally, do not use a solution containing benzyl alcohol. This pharmacy bulk package is not intended to be used for the preparation of intrathecal doses.
Cytarabine given intrathecally may cause systemic toxicity and careful monitoring of the hemopoietic system is indicated. Modification of other anti-leukemia therapy may be necessary. Major toxicity is rare. The most frequently reported reactions after intrathecal administration were nausea, vomiting and fever; these reactions are mild and self-limiting. Paraplegia has been reported. Necrotizing leukoencephalopathy occurred in 5 children; these patients had also been treated with intrathecal methotrexate and hydrocortisone, as well as by central nervous system radiation. Isolated neurotoxicity has been reported. Blindness occurred in two patients in remission whose treatment had consisted of combination systemic chemotherapy, prophylactic central nervous system radiation and intrathecal cytarabine.
When cytarabine is administered both intrathecally and intravenously within a few days, there is an increased risk of spinal cord toxicity, however, in serious life-threatening disease, concurrent use of intravenous and intrathecal cytarabine is left to the discretion of the treating physician.
Focal leukemic involvement of the central nervous system may not respond to intrathecal cytarabine and may better be treated with radiotherapy.
Chemical Stability of Infusion Solutions:
This chemical stability information in no way indicates that it would be acceptable practice to infuse a cytarabine admixture well after the preparation time. Good professional practice suggests that administration of an admixture should be as soon after preparation as feasible.
Parenteral drugs should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.
Handling and Disposal: Procedures for proper handling and disposal of anti-cancer drugs should be considered. Several guidelines on this subject have been published.1-7 There is no general agreement that all of the procedures recommended in the guidelines are necessary or appropriate.
Direction for Dispensing From Pharmacy Bulk Package: The 50 mL Pharmacy Bulk Package is for use in the Pharmacy Admixtures Service only. The vials should be inserted into the plastic handling device provided, suspended as a unit in the laminar flow hood.
A single entry through the vial closure should be made with a sterile dispensing set or transfer device. Transfer individual doses to appropriate intravenous infusion solutions. Use of a syringe with needle is not recommended. Multiple entries will increase the potential of microbial and particulate contamination.
The above process should be carried out under a laminar flow hood using aseptic technique. Care should be exercised to protect personnel from aerosolized drug (see DOSAGE AND ADMINISTRATION, REFERENCES). Discard any unused portion within 4 hours after initial closure entry.
Cytarabine Injection 20 mg/mL (1000 mg) in a 50 mL flip-top vial (green cap), packaged individually. Store product at controlled room temperature, 15° - 30°C (59° - 86°F).
2 g/20 mL in a single dose flip top vial (green cap) packaged individually.
Cytarabine Injection 20 mg/mL (500 mg/25 mL) in a multidose flip-top vial (red cap), packaged individually. Store at controlled room temperature, 15° - 30°C (59° - 86°F).
1) [PACKAGE INSERT DATA] : cytarabine (CYTARABINE) injection, solution. Mayne Pharma (USA) Inc. Paramus, NJ 07652. Revision Date January 2004.
2) Solimando, Dominic A. Drug Information Handbook for Oncology: A Complete Guide to Combination Chemotherapy Regimens, 8th ed. Hudson, OH: Lexi-Comp, Inc.; 2010.
Handling and Disposal: Recommendations for the Safe handling of Parenteral Antineoplastic Drugs, NIH Publications No. 83-2621. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington , D.C. 20402. AMA Council Report, Guidelines for Handling Parenteral Antineoplastics, JAMA, 1985; 2.53 (11): 1590-1592. National Study Commission on Cytotoxic Exposure - Recommendations for Handling Cytotoxic Agents. Available from Louis P. Jeffrey, ScD., Chairman, National Study Commission on Cytotoxic Exposure, Massachusetts College of Pharmacy and Allied Health Sciences, 179 Longwood Avenue, Boston, Massachusetts 02115. Clinical Oncological Society of Australia, Guidelines and Recommendations for Safe handling of Antineoplastic Agents. Med J Australia, 1983; 1:426-428. Jones RB, et al: Safe Handling of Chemotherapeutic Agents: A Report from the Mount Sinai Medical Center. CA-A Cancer Journal of Clinicians, 1983; (Sept/Oct) 258-263. American Society of Hospital Pharmacists Technical Assistance Bulletin on Handling Cytotoxic and Hazardous Drugs. Am J. Hosp. Pharm, 1990; 47:1033-1049. Controlling Occupational Exposure to Hazardous Drugs. (OSHA Work Practice Guidelines), Am J. Health-Syst Pharm, 1996; 53: 1669-1685.