Metabolic fate of radioactive acyclovir in humans

Journal Article · Tue Jul 20 04:00:00 EDT 1982 · Am. J. Med.; (United States)

DOI:https://doi.org/10.1016/0002-9343(82)90094-8· OSTI ID:6705199

de Miranda, P; Good, S S; Krasny, H C; Connor, J D; Laskin, O L; Lietman, P S

The metabolic fate and the kinetics of elimination of (8-/sup 14/C)acyclovir in plasma and blood was investigated in five cancer patients. Doses of 0.5 and 2.5 mg/kg were administered by one-hour intravenous infusion. Radioactivity was distributed nearly equally in blood and plasma. The plasma and blood concentration-time data were defined by a two-compartment open pharmacokinetic model. The overall mean acyclovir plasma half-life and total body clearance +/- SD were 2.1 +/- 0.5 hours and 297 +/- 53 ml/min/1.73 m2. Binding of acyclovir to plasma proteins was 15.4 +/- 4.4 percent. The radioactive dose was excreted predominantly in the urine (71 to 99 percent) with less than 2 percent excretion in the feces and only trace amounts of radioactivity in the expired air. Reverse-phase high-performance liquid chromatography indicated that 9-carboxymethoxymethylguanine was the only significant urinary metabolite of acyclovir accounting for 8.5 to 14.1 percent of the dose. A minor metabolite (less than 0.2 percent of dose) had the retention time of 8-hydroxy-9-(2-hydroxyethoxymethyl)guanine. Unchanged urinary acyclovir ranged from 62 to 91 percent of the dose. There was no indication of acyclovir cleavage to guanine. The renal clearances of acyclovir were three times higher than the corresponding creatinine clearances.

• Research Organization: Wellcome Research Laboratories, Research Triangle Park, North Carolina
• OSTI ID: 6705199
• Journal Information: Am. J. Med.; (United States), Journal Name: Am. J. Med.; (United States) Vol. 73:1A; ISSN AJMEA
• Country of Publication: United States
• Language: English

Related Subjects

550201 -- Biochemistry-- Tracer Techniques
550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BLOOD
BLOOD PLASMA
BODY FLUIDS
CARBON 14 COMPOUNDS
CHEMOTHERAPY
CLEARANCE
DISEASES
DRUGS
EXCRETION
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MATERIALS
METABOLISM
METABOLITES
NEOPLASMS
PATHOLOGY
PATIENTS
REACTION KINETICS
RENAL CLEARANCE
THERAPY
TRACER TECHNIQUES
URINE
WASTES