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The Clinical Pharmacokinetics of Famciclovir

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  • Drug Disposition
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Summary

Famciclovir is an oral prodrug of the antiherpesvirus nucleoside analogue, penciclovir. Following oral administration famciclovir undergoes extensive first pass metabolism to penciclovir and essentially no parent compound is recovered from plasma or urine. Penciclovir plasma concentrations reach a maximum less than 1 hour after famciclovir administration in fasting individuals, but are delayed if famciclovir is taken within 2 hours of a meal. The bioavailability of penciclovir, measured by urinary recovery, is approximately 60% and is not affected by food. Over the likely therapeutic dose range of famciclovir 125mg to 750mg, the pharmacokinetics of penciclovir are linear.

The volume of distribution of penciclovir after intravenous administration is more than 1 L/kg, indicating extensive distribution into the tissue. Penciclovir is predominantly eliminated unchanged by the kidney, partly by active tubular excretion and has a terminal phase elimination half-life (t½β) of between 2 and 2.5 hours and a renal clearance (CLR) of between 25 and 30 L/h in individuals with normal renal function. In those with severe renal impairment the CLR falls markedly and the t½β increases to over 18 hours. Haemodialysis appears to be effective in clearing penciclovir from plasma.

Elderly individuals tolerate famciclovir well, despite slower elimination secondary to age-related lower renal clearance. Uncomplicated herpes zoster does not affect the pharmacokinetic profile of penciclovir. In the limited studies undertaken so far, no significant drug interactions have been demonstrated.

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References

  1. de Miranda P, Blum MR. Pharmacokinetics of acyclovir after intravenous and oral administration. J Antimicrob Chemother 1983; 12 Suppl. B: 29–37

    PubMed  Google Scholar 

  2. Vere Hodge RA. Famciclovir and penciclovir: the mode of action of famciclovir including its conversion to penciclovir. Antivir Chem Chemother 1993; 4: 67–84

    CAS  Google Scholar 

  3. McMeekin JR, Fowles SE, Winton CF, et al. Rapid high-performance liquid Chromatographic method for the analysis of the active antiherpes agent, penciclovir and its precursor, BRL 43259, in human plasma and urine following administration of the oral prodrug, famciclovir. Analytical Proc 1992; 29: 178–80

    CAS  Google Scholar 

  4. Clarke SE, Harrell AW, Chenery RJ. Role of aldehyde oxidase in the in vitro conversion of famciclovir to penciclovir in human liver. Drug Metab Dispos 1995; 23: 251–4

    PubMed  CAS  Google Scholar 

  5. Winton CF, Fowles SE, Vere Hodge RA, et al. Assay of famciclovir and its metabolites, including the antiherpes agent penciclovir,in plasma and urine of rat, dog and man. In: Reid E, Wilson ID, editors. Analysis of drugs and metabolites. Cambridge (UK): Royal Society of Chemistry, 1990: 163–71

    Google Scholar 

  6. Pue MA, Pratt SK, Fairless AJ, et al. Linear pharmacokinetics of penciclovir following administration of single oral doses of famciclovir 125, 250, 500 and 750 mg to healthy volunteers. J Antimicrob Chemother 1994; 33: 119–27

    Article  PubMed  CAS  Google Scholar 

  7. Pratt SK, Fairless AJ, Pue MA, et al. The absolute bioavailability of the antiviral compound, penciclovir, following a single oral administration of 500mg famciclovir [abstract B118]. Programme and abstracts of the 3rd Congress of the European Academy of Dermatology and Venereology; 1993 Sep 26–30: Copenhagen

  8. Fowles SE, Pierce DM, Prince WT, et al. Effect of food on the bioavailability and pharmacokinetics of penciclovir, a novel antiherpes agent, following oral administration of the prodrug, famciclovir. Br J Clin Pharmacol 1990; 29: 620P–21P

    Google Scholar 

  9. Fowles SE, Fairless AJ, Pierce DM, et al. A further study of the effect of food on the bioavailability and pharmacokinetics of penciclovir after oral administration of famciclovir. Br J Clin Pharmacol 1991; 32: 657P

  10. Pue MA, Benet LZ. Pharmacokinetics of famciclovir in man. Antivir Chem Chemother 1993; 4 Suppl. 1: 47–55

    CAS  Google Scholar 

  11. Fowles SE, Pierce DM, Prince WT, et al. The tolerance to and pharmacokinetics of penciclovir (BRL 39, 123A), a novel antiherpes agent, administered by intravenous infusion to healthy subjects. Eur J Clin Pharmacol 1992; 43: 513–6

    Article  PubMed  CAS  Google Scholar 

  12. Vere Hodge RA, Cheng Y-C. The mode of action of penciclovir. Antivir Chem Chemother 1993; 4 Suppl. 1: 13–24

    Google Scholar 

  13. Earnshaw DL, Bacon TH, Darlison SJ, et al. Mode of action of penciclovir in MRC-5 cells infected with herpes simplex virus type 1 (HSV-1), HSV-2, and varicella-zoster virus. Antimicrob Agents Chemother 1992; 36: 2742–57

    Article  Google Scholar 

  14. Boyd MR, Safrin S, Kerne R. Penciclovir: a review of its spectrum of activity, selective and cross-resistant pattern. Antivir Chem Chemother 1993; 4 Suppl. 1: 3–11

    CAS  Google Scholar 

  15. Bacon TH. Moving forward: research and development of a novel antiviral agent. Res Clin Forums 1995; 17(3): 35–44

    Google Scholar 

  16. Boike SC, Pue MA, Freed MI, et al. Pharmacokinetics of famciclovir in subjects with varying degrees of renal impairment. Clin Pharmacol Ther 1994; 55: 418–26

    Article  PubMed  CAS  Google Scholar 

  17. Filer CW, Allen GD, Brown TA, et al. Metabolic and pharmacokinetic studies following oral administration of 14C-famciclovir to healthy subjects. Xenobiotica 1994; 24: 357–68

    Article  PubMed  CAS  Google Scholar 

  18. Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron 1976; 16: 31–41

    Article  PubMed  CAS  Google Scholar 

  19. Pratt SK, Fairless AJ, Pue MA, et al. The haemodialysis of penciclovir [abstract 1286]. Abstracts of 6th International Congress for Infectious Diseases; 1994 Apr 26–30; Prague

  20. Pue MA, Boike SC, Freed MI, et al. Pharmacokinetics of penciclovir in subjects with hepatic insufficiency following oral famciclovir. Br J Clin Pharmacol 1994; 37: 494P

  21. Fowles SE, Pue MA, Pierce D, et al. Pharmacokinetics of penciclovir in healthy elderly subjects following a single oral administration of 750 mg famciclovir. Br J Clin Pharmacol 1992; 35: 450P

  22. Gross G, Wood M, Siederer SK, et al. Penciclovir pharmacokinetics in patients with uncomplicated herpes zoster following oral administration of 250 mg famciclovir [abstract 856]. Abstracts of 7th European Congress of Clinical Microbiology and Infectious Diseases; 1995 Mar 26–30; Vienna. 166–7

  23. Pratt SK, Beerahee M, Pue MA, et al. The pharmacokinetics of penciclovir following oral administration of 500mg famciclovir to patients with uncomplicated herpes zoster infection [abstract B119]. Programme and abstracts of the 3rd Congress of the European Academy of Dermatology and Venereology; 1993 Sep 26–30; Copenhagen

  24. Daniels S, Schentag JJ. Drug interaction studies and safety of famciclovir in healthy volunteers: a review. Antivir Chem Chemother 1993; 4 Suppl. 1: 57–64

    CAS  Google Scholar 

  25. Siederer S, Scott S, Rousseau F, et al. Pharmacokinetics of penciclovir following co-administration of famciclovir with zidovudine to HIV positive patients [abstract 855]. Abstracts of 7th European Congress of Clinical Microbiology and Infectious Diseases; 1995 Mar 26–30; Vienna. 166

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Gill, K.S., Wood, M.J. The Clinical Pharmacokinetics of Famciclovir. Clin-Pharmacokinet 31, 1–8 (1996). https://doi.org/10.2165/00003088-199631010-00001

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