Analyze Diet
Veterinary ophthalmology2020; 23(4); 640-647; doi: 10.1111/vop.12764

Utility of systemic voriconazole in equine keratomycosis based on pharmacokinetic-pharmacodynamic analysis of tear fluid following oral administration.

Abstract: To clarify the detailed pharmacokinetics (PK) of orally administered voriconazole in tear fluid (TF) of horses for evaluating the efficacy of voriconazole secreted into TF against equine keratomycosis. Methods: Five healthy Thoroughbred horses. Methods: Voriconazole was administrated through a nasogastric tube to each horse at a single dose of 4.0 mg/kg. TF and blood samples were collected before and periodically throughout the 24 hours after administration. Voriconazole concentrations in plasma and TF samples were analyzed using liquid chromatography-electrospray tandem-mass spectrometry. The predicted voriconazole concentration in both samples following multiple dosing every 24 hours was simulated by the superposition principle. Results: The mean maximum voriconazole concentrations in plasma and TF were 3.3 μg/mL at 1.5 h and 1.9 μg/mL at 1.6 h, respectively. Mean half-life in both samples were 16.4 and 25.2 h, respectively. The ratio of predicted AUC at steady state in TF (51.3 μg∙h/mL) to previously published minimum inhibitory concentration (MIC) of Aspergillus and Fusarium species was >100 and 25.7, respectively. Conclusions: This study demonstrated the detailed single-dose PK of voriconazole in TF after oral administration and simulated the predicted concentration curves in a multiple oral dosing. Based on the analyses of PK-PD, the simulation results indicated that repeated oral administration of voriconazole at 4.0 mg/kg/d achieves the ratio of AUC to MIC associated with treatment efficacy against Aspergillus species. The detailed PK-PD analyses against pathogenic fungi in TF can be used to provide evidence-based medicine for equine keratomycosis.
Publication Date: 2020-05-08 PubMed ID: 32383526PubMed Central: PMC7496923DOI: 10.1111/vop.12764Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigates the efficiency of a drug named voriconazole in treating horse eye infections known as equine keratomycosis. By studying how the drug moves and behaves in the horse’s body after oral administration, the research provides evidence suggesting that repeated dosages are effective in treating infections caused by a type of fungus.

Methodology

  • The study involved five healthy Thoroughbred horses, in which voriconazole was administered orally at a dosage of 4.0 mg/kg.
  • Both tear fluid and blood samples were collected from the horses before and after the drug administration for 24 hours.
  • The collected samples were then analyzed using a sophisticated technique called liquid chromatography-electrospray tandem-mass spectrometry. This procedure allowed the researchers to determine the concentration of voriconazole in the plasma and tear fluid.
  • The researchers predicted the level of voriconazole in these samples after multiple doses in a 24-hour period using a mathematical calculation known as the superposition principle.

Results

  • The experiment revealed that the highest concentrations of voriconazole in blood and tear fluid occurred 1.5 hours and 1.6 hours after drug administration, respectively, with mean maximum concentrations of 3.3 μg/mL in plasma and 1.9 μg/mL in tear fluid.
  • The study also found the half-life of the drug, which is the time it takes for the drug concentration to decrease by half, was 16.4 hours in plasma and 25.2 hours in tear fluid.
  • The predicted concentration of voriconazole in tear fluid (51.3 μg∙h/mL) was found to be significantly larger than the minimum inhibitory concentration (MIC) needed to prevent the growth of Aspergillus and Fusarium fungi, meaning the drug was effectively killing these organisms.

Conclusions

  • The study provided detailed information about the pharmacokinetics (behaviour of the drug in the body) of voriconazole in tear fluid after a single oral dose, as well as projected concentrations with multiple dosage.
  • Based on these analyses, the study concluded that repeated oral administration of voriconazole at 4.0 mg/kg/d should be effective against Aspergillus species.
  • This research provides evidence-based guidance for using voriconazole in treating equine keratomycosis.

Cite This Article

APA
Tamura N, Okano A, Kuroda T, Niwa H, Kusano K, Matsuda Y, Fukuda K, Mita H, Nagata S. (2020). Utility of systemic voriconazole in equine keratomycosis based on pharmacokinetic-pharmacodynamic analysis of tear fluid following oral administration. Vet Ophthalmol, 23(4), 640-647. https://doi.org/10.1111/vop.12764

Publication

ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English
Volume: 23
Issue: 4
Pages: 640-647

Researcher Affiliations

Tamura, Norihisa
  • Miho Training Center, Japan Racing Association, Racehorse Hospital, Ibaraki, Japan.
  • Japan Racing Association, Equine Research Institute, Tochigi, Japan.
Okano, Atsushi
  • Miho Training Center, Japan Racing Association, Racehorse Hospital, Ibaraki, Japan.
Kuroda, Taisuke
  • Miho Training Center, Japan Racing Association, Racehorse Hospital, Ibaraki, Japan.
Niwa, Hidekazu
  • Japan Racing Association, Equine Research Institute, Tochigi, Japan.
Kusano, Kanichi
  • Miho Training Center, Japan Racing Association, Racehorse Hospital, Ibaraki, Japan.
Matsuda, Yoshikazu
  • Miho Training Center, Japan Racing Association, Racehorse Hospital, Ibaraki, Japan.
Fukuda, Kentaro
  • Miho Training Center, Japan Racing Association, Racehorse Hospital, Ibaraki, Japan.
Mita, Hiroshi
  • Japan Racing Association, Equine Research Institute, Tochigi, Japan.
Nagata, Shunichi
  • Laboratory of Racing Chemistry, Tochigi, Japan.

MeSH Terms

  • Administration, Oral
  • Animals
  • Antifungal Agents / administration & dosage
  • Antifungal Agents / pharmacokinetics
  • Antifungal Agents / pharmacology
  • Antifungal Agents / therapeutic use
  • Area Under Curve
  • Aspergillus / drug effects
  • Eye Infections, Fungal / drug therapy
  • Eye Infections, Fungal / veterinary
  • Female
  • Horse Diseases / blood
  • Horse Diseases / drug therapy
  • Horses / metabolism
  • Male
  • Microbial Sensitivity Tests
  • Tears / metabolism
  • Voriconazole / administration & dosage
  • Voriconazole / pharmacokinetics
  • Voriconazole / pharmacology
  • Voriconazole / therapeutic use

References

This article includes 42 references
  1. GalÁn A, MartÍn‐SuÁrez EM, Gallardo JM, Molleda JM. Clinical findings and progression of 10 cases of equine ulcerative keratomycosis (2004–2007).. Equine Vet Educ 2009;21:236‐242.
  2. Coad CT, Robinson NM, Wilhelmus KR. Antifungal sensitivity testing for equine keratomycosis.. Am J Vet Res 1985 Mar;46(3):676-8.
    pubmed: 3994133
  3. Brooks DE. Equine keratomycosis: an international problem.. Equine Vet Educ 2009;21:243‐246.
  4. Nasisse MP, Nelms S. Equine ulcerative keratitis.. Vet Clin North Am Equine Pract 1992 Dec;8(3):537-55.
    pubmed: 1458328doi: 10.1016/s0749-0739(17)30440-6google scholar: lookup
  5. Hamor RE, Whelan NC. Equine infectious keratitis.. Vet Clin North Am Equine Pract 1999 Dec;15(3):623-46.
    pubmed: 10589471doi: 10.1016/s0749-0739(17)30136-0google scholar: lookup
  6. Brooks DE, Andrew SE, Dillavou CL, Ellis G, Kubilis PS. Antimicrobial susceptibility patterns of fungi isolated from horses with ulcerative keratomycosis.. Am J Vet Res 1998 Feb;59(2):138-42.
    pubmed: 9492925
  7. Ledbetter EC, Patten VH, Scarlett JM, Vermeylen FM. In vitro susceptibility patterns of fungi associated with keratomycosis in horses of the northeastern United States: 68 cases (1987-2006).. J Am Vet Med Assoc 2007 Oct 1;231(7):1086-91.
    pubmed: 17916036doi: 10.2460/javma.231.7.1086google scholar: lookup
  8. Wada S, Hobo S, Ode H, Niwa H, Moriyama H. Equine keratomycosis in Japan.. Vet Ophthalmol 2013 Jan;16(1):1-9.
  9. Sansom J, Featherstone H, Barnett KC. Keratomycosis in six horses in the United Kingdom.. Vet Rec 2005 Jan 1;156(1):13-7.
    pubmed: 15658562doi: 10.1136/vr.156.1.13google scholar: lookup
  10. Gaarder JE, Rebhun WC, Ball MA, Patten V, Shin S, Erb H. Clinical appearances, healing patterns, risk factors, and outcomes of horses with fungal keratitis: 53 cases (1978-1996).. J Am Vet Med Assoc 1998 Jul 1;213(1):105-12.
    pubmed: 9656035
  11. Andrew SE, Brooks DE, Smith PJ, Gelatt KN, Chmielewski NT, Whittaker CJ. Equine ulcerative keratomycosis: visual outcome and ocular survival in 39 cases (1987-1996).. Equine Vet J 1998 Mar;30(2):109-16.
  12. Marangon FB, Miller D, Giaconi JA, Alfonso EC. In vitro investigation of voriconazole susceptibility for keratitis and endophthalmitis fungal pathogens.. Am J Ophthalmol 2004 May;137(5):820-5.
    pubmed: 15126145doi: 10.1016/j.ajo.2003.11.078google scholar: lookup
  13. Johnson EM, Szekely A, Warnock DW. In-vitro activity of voriconazole, itraconazole and amphotericin B against filamentous fungi.. J Antimicrob Chemother 1998 Dec;42(6):741-5.
    pubmed: 10052897doi: 10.1093/jac/42.6.741google scholar: lookup
  14. Espinel-Ingroff A. In vitro activity of the new triazole voriconazole (UK-109,496) against opportunistic filamentous and dimorphic fungi and common and emerging yeast pathogens.. J Clin Microbiol 1998 Jan;36(1):198-202.
    pmc: PMC124833pubmed: 9431946doi: 10.1128/jcm.36.1.198-202.1998google scholar: lookup
  15. Radford SA, Johnson EM, Warnock DW. In vitro studies of activity of voriconazole (UK-109,496), a new triazole antifungal agent, against emerging and less-common mold pathogens.. Antimicrob Agents Chemother 1997 Apr;41(4):841-3.
    pmc: PMC163806pubmed: 9087501doi: 10.1128/aac.41.4.841google scholar: lookup
  16. Clode AB, Davis JL, Salmon J, Michau TM, Gilger BC. Evaluation of concentration of voriconazole in aqueous humor after topical and oral administration in horses.. Am J Vet Res 2006 Feb;67(2):296-301.
    pubmed: 16454636doi: 10.2460/ajvr.67.2.296google scholar: lookup
  17. Brooks DE, Matthews A, Clode AB. Diseases of the cornea. In: Gilger BC, eds. Equine Ophthalmology, 3rd ed Hoboken, NJ: John Wiley & Sons, Inc; 2016:252‐368.
  18. Smith KM, Maxwell L, Gull T, Payton ME, Gilmour MA. Stability of 1% voriconazole solution in a constant-rate infusion pump for topical ocular delivery to horses.. Vet Ophthalmol 2014 Jul;17 Suppl 1:82-9.
    pubmed: 24602272doi: 10.1111/vop.12155google scholar: lookup
  19. Matthews AG. Ophthalmic antimicrobial therapy in the horse.. Equine Vet Educ 2009;21:271‐280.
  20. Colitz CM, Latimer FG, Cheng H, Chan KK, Reed SM, Pennick GJ. Pharmacokinetics of voriconazole following intravenous and oral administration and body fluid concentrations of voriconazole following repeated oral administration in horses.. Am J Vet Res 2007 Oct;68(10):1115-21.
    pubmed: 17916020doi: 10.2460/ajvr.68.10.1115google scholar: lookup
  21. Passler NH, Chan HM, Stewart AJ, Duran SH, Welles EG, Lin HC, Ravis WR. Distribution of voriconazole in seven body fluids of adult horses after repeated oral dosing.. J Vet Pharmacol Ther 2010 Feb;33(1):35-41.
  22. Davis JL, Salmon JH, Papich MG. Pharmacokinetics of voriconazole after oral and intravenous administration to horses.. Am J Vet Res 2006 Jun;67(6):1070-5.
    pubmed: 16740104doi: 10.2460/ajvr.67.6.1070google scholar: lookup
  23. Collum LM, McGettrick P, Akhtar J, Lavin J, Rees PJ. Oral acyclovir (Zovirax) in herpes simplex dendritic corneal ulceration.. Br J Ophthalmol 1986 Jun;70(6):435-8.
    pmc: PMC1041036pubmed: 3521717doi: 10.1136/bjo.70.6.435google scholar: lookup
  24. Gerhardt N, Schulz BS, Werckenthin C, Hartmann K. Pharmacokinetics of enrofloxacin and its efficacy in comparison with doxycycline in the treatment of Chlamydophila felis infection in cats with conjunctivitis.. Vet Rec 2006 Oct 28;159(18):591-4.
    pubmed: 17071671doi: 10.1136/vr.159.18.591google scholar: lookup
  25. Baker A, Plummer CE, Szabo NJ, Barrie KP, Brooks DE. Doxycycline levels in preocular tear film of horses following oral administration.. Vet Ophthalmol 2008 Nov-Dec;11(6):381-5.
  26. Thomasy SM, Covert JC, Stanley SD, Maggs DJ. Pharmacokinetics of famciclovir and penciclovir in tears following oral administration of famciclovir to cats: a pilot study.. Vet Ophthalmol 2012 Sep;15(5):299-306.
  27. Hartmann A, Krebber R, Daube G, Hartmann K. Pharmacokinetics of pradofloxacin and doxycycline in serum, saliva, and tear fluid of cats after oral administration.. J Vet Pharmacol Ther 2008 Apr;31(2):87-94.
  28. Amorós-Reboredo P, Bastida-Fernandez C, Guerrero-Molina L, Soy-Muner D, López-Cabezas C. Stability of frozen 1% voriconazole ophthalmic solution.. Am J Health Syst Pharm 2015 Mar 15;72(6):479-82.
    pubmed: 25736943doi: 10.2146/ajhp140127google scholar: lookup
  29. Pfaller JB, Messer SA, Hollis RJ, Diekema DJ, Pfaller MA. In vitro susceptibility testing of Aspergillus spp.: comparison of Etest and reference microdilution methods for determining voriconazole and itraconazole MICs.. J Clin Microbiol 2003 Mar;41(3):1126-9.
  30. Lalitha P, Shapiro BL, Srinivasan M, Prajna NV, Acharya NR, Fothergill AW, Ruiz J, Chidambaram JD, Maxey KJ, Hong KC, McLeod SD, Lietman TM. Antimicrobial susceptibility of Fusarium, Aspergillus, and other filamentous fungi isolated from keratitis.. Arch Ophthalmol 2007 Jun;125(6):789-93.
    pubmed: 17562990doi: 10.1001/archopht.125.6.789google scholar: lookup
  31. Fukuda M, Murano H, Sasaki K. [Dynamics of fluoroquinolone agents in tear fluid--a comparison of the dynamic in tears of human and rabbit eyes].. Nippon Ganka Gakkai Zasshi 1994 Aug;98(8):721-6.
    pubmed: 7942332
  32. Mouton JW, Dudley MN, Cars O, Derendorf H, Drusano GL. Standardization of pharmacokinetic/pharmacodynamic (PK/PD) terminology for anti-infective drugs: an update.. J Antimicrob Chemother 2005 May;55(5):601-7.
    pubmed: 15772142doi: 10.1093/jac/dki079google scholar: lookup
  33. Theuretzbacher U, Ihle F, Derendorf H. Pharmacokinetic/pharmacodynamic profile of voriconazole.. Clin Pharmacokinet 2006;45(7):649-63.
  34. Hollis AR, Wilkins PA. Current controversies in equine antimicrobial therapy.. Equine Vet Educ 2009;21:216‐224.
  35. Vishkautsan P, Papich MG, Thompson GR 3rd, Sykes JE. Pharmacokinetics of voriconazole after intravenous and oral administration to healthy cats.. Am J Vet Res 2016 Sep;77(9):931-9.
    pubmed: 27580104doi: 10.2460/ajvr.77.9.931google scholar: lookup
  36. Lemetayer JD, Dowling PM, Taylor SM, Papich MG. Pharmacokinetics and distribution of voriconazole in body fluids of dogs after repeated oral dosing.. J Vet Pharmacol Ther 2015 Oct;38(5):451-6.
    pubmed: 25691353doi: 10.1111/jvp.12208google scholar: lookup
  37. Hyland R, Jones BC, Smith DA. Identification of the cytochrome P450 enzymes involved in the N-oxidation of voriconazole.. Drug Metab Dispos 2003 May;31(5):540-7.
    pubmed: 12695341doi: 10.1124/dmd.31.5.540google scholar: lookup
  38. Lepak AJ, Andes DR. Antifungal pharmacokinetics and pharmacodynamics.. Cold Spring Harb Perspect Med 2014 Nov 10;5(5):a019653.
    pmc: PMC4448584pubmed: 25384765doi: 10.1101/cshperspect.a019653google scholar: lookup
  39. Mavridou E, Bruggemann RJ, Melchers WJ, Verweij PE, Mouton JW. Impact of cyp51A mutations on the pharmacokinetic and pharmacodynamic properties of voriconazole in a murine model of disseminated aspergillosis.. Antimicrob Agents Chemother 2010 Nov;54(11):4758-64.
    pmc: PMC2976127pubmed: 20733046doi: 10.1128/aac.00606-10google scholar: lookup
  40. Manavathu EK, Cutright JL, Chandrasekar PH. Organism-dependent fungicidal activities of azoles.. Antimicrob Agents Chemother 1998 Nov;42(11):3018-21.
    pmc: PMC105986pubmed: 9797246doi: 10.1128/aac.42.11.3018google scholar: lookup
  41. Krishnan S, Manavathu EK, Chandrasekar PH. A comparative study of fungicidal activities of voriconazole and amphotericin B against hyphae of Aspergillus fumigatus.. J Antimicrob Chemother 2005 Jun;55(6):914-20.
    pubmed: 15824093doi: 10.1093/jac/dki100google scholar: lookup
  42. Purkins L, Wood N, Kleinermans D, Greenhalgh K, Nichols D. Effect of food on the pharmacokinetics of multiple-dose oral voriconazole.. Br J Clin Pharmacol 2003 Dec;56 Suppl 1(Suppl 1):17-23.

Citations

This article has been cited 1 times.
  1. Bowden AC, Allbaugh RA, Smith JS, Mochel JP, Sebbag L. Kinetics and minimal inhibitory concentrations of ceftiofur in tear film following extended-release parenteral administration (Excede(®)) in dogs.. Front Vet Sci 2022;9:975113.
    doi: 10.3389/fvets.2022.975113pubmed: 36213401google scholar: lookup