Cerebrospinal Fluid and Plasma Pharmacokinetics of High Doses of 1-β-D-Arabinofuranosylcytosine in Nonhuman Primates

Jose A. Lopez, John G. Krikoriar, Ram P. Agarwal, G. Peter Beardsley, Ronald W. Mortara

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

The pharmacokinetics of 1-β-D-arabinofuranosylcytosine (ara-C) in plasma, cerebrospinal fluid (CSF), and urine was studied in nonhuman primates. Conventional and high-dose schedules of ara-C were administered i.v. and intraventricularly through indwelling Ommaya reservoirs. ara-C and its metabolite 1-β-D-arabinofuranosyluracil (ara-U) were measured by high-pressure liquid chromatography. Due to rapid peripheral deamination (230 nm ara-C/hr/ml plasma), the half-life of ara-C in plasma after a 140-mg/kg i.v. 1-hr infusion was short (3.7 min). Peak plasma concentrations of ara-C, ranging between <0.1 and 49 μg/ml, were dose dependent (ara-C, 15 to 140 mg/kg). Under these conditions, ara-C was undetectable in CSF. About 53% of the administered dose (140 mg/kg) was excreted in urine during the first 5 hr mostly as ara-U. Intraventricular administration of 50 and 250 mg of ara-C resulted in peak lumbar CSF levels of 435 and 2235 μg/ml, respectively, at about 155 and 80 min postinjection. Concomitant ara-U levels were one-tenth of those of ara-C and increased progressively, suggesting deamination of the drug in the central nervous system. The half-life of ara-C in CSF ranged between 50 and 60 min. Administration of 50 mg of ara-U intraventricularly resulted in peak lumbar ara-U levels of 595 μg/ml at about 180 min with a prolonged clearance. Concomitant plasma levels throughout the study were less than 0.1 μg/ml, suggesting slower equilibrium. No hematological or nervous system toxicity was observed during these studies. The clinical implications of these findings are discussed.

Original languageEnglish (US)
Pages (from-to)5190-5193
Number of pages4
JournalCancer Research
Volume43
Issue number11
StatePublished - Nov 1 1983

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

Fingerprint Dive into the research topics of 'Cerebrospinal Fluid and Plasma Pharmacokinetics of High Doses of 1-β-D-Arabinofuranosylcytosine in Nonhuman Primates'. Together they form a unique fingerprint.

  • Cite this

    Lopez, J. A., Krikoriar, J. G., Agarwal, R. P., Beardsley, G. P., & Mortara, R. W. (1983). Cerebrospinal Fluid and Plasma Pharmacokinetics of High Doses of 1-β-D-Arabinofuranosylcytosine in Nonhuman Primates. Cancer Research, 43(11), 5190-5193.