This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Firsov, A. A.
Right arrow Articles by Zinner, S. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Firsov, A. A.
Right arrow Articles by Zinner, S. H.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, November 1998, p. 2841-2847, Vol. 42, No. 11
0066-4804/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

A New Approach to In Vitro Comparisons of Antibiotics in Dynamic Models: Equivalent Area under the Curve/MIC Breakpoints and Equiefficient Doses of Trovafloxacin and Ciprofloxacin against Bacteria of Similar Susceptibilities

Alexander A. Firsov,1,* Sergey N. Vostrov,1 Alexander A. Shevchenko,1 Yury A. Portnoy,1 and Stephen H. Zinner2

Department of Pharmacokinetics, Centre of Science & Technology LekBioTech, Moscow 117246, Russia,1 and Division of Infectious Diseases, Roger Williams Medical Center, Rhode Island Hospital, Brown University, Providence, Rhode Island2

Received 30 January 1998/Returned for modification 19 May 1998/Accepted 10 August 1998

Time-kill studies, even those performed with in vitro dynamic models, often do not provide definitive comparisons of different antimicrobial agents. Also, they do not allow determinations of equiefficient doses or predictions of area under the concentration-time curve (AUC)/MIC breakpoints that might be related to antimicrobial effects (AMEs). In the present study, a wide range of single doses of trovafloxacin (TR) and twice-daily doses of ciprofloxacin (CI) were mimicked in an in vitro dynamic model. The AMEs of TR and CI against gram-negative bacteria with similar susceptibilities to both drugs were related to AUC/MICs that varied over similar eight-fold ranges [from 54 to 432 and from 59 to 473 (µg · h/ml)/(µg/ml), respectively]. The observation periods were designed to include complete bacterial regrowth, and the AME was expressed by its intensity (the area between the control growth in the absence of antibiotics and the antibiotic-induced time-kill and regrowth curves up to the point where viable counts of regrowing bacteria equal those achieved in the absence of drug [IE]). In each experiment monoexponential pharmacokinetic profiles of TR and CI were simulated with half-lives of 9.2 and 4.0 h, respectively. Linear relationships between IE and log AUC/MIC were established for TR and CI against three bacteria: Escherichia coli (MIC of TR [MICTR] = 0.25 µg/ml; MIC of CI [MICCI] = 0.12 µg/ml), Pseudomonas aeruginosa (MICTR = 0.3 µg/ml; MICCI = 0.15 µg/ml), and Klebsiella pneumoniae (MICTR = 0.25 µg/ml; MICCI = 0.12 µg/ml). The slopes and intercepts of these relationships differed for TR and CI, and the IE-log AUC/MIC plots were not superimposed, although they were similar for all bacteria with a given antibiotic. By using the relationships between IE and log AUC/MIC, TR was more efficient than CI. The predicted value of the AUC/MIC breakpoint for TR [mean for all three bacteria, 63 (µg · h/ml)/(µg/ml)] was approximately twofold lower than that for CI. Based on the IE-log AUC/MIC relationships, the respective dose (D)-response relationships were reconstructed. Like the IE-log AUC/MIC relationships, the IE-log D plots showed TR to be more efficient than CI. Single doses of TR that are as efficient as two 500-mg doses of CI (500 mg given every 12 h) were similar for the three strains (199, 226, and 203 mg). This study suggests that in vitro evaluation of the relationships between IE and AUC/MIC or D might be a reliable basis for comparing different fluoroquinolones and that the results of such comparative studies may be highly dependent on their experimental design and datum quantitation.


* Corresponding author. Mailing address: Department of Pharmacokinetics, Centre of Science & Technology LekBioTech, 8 Nauchny proezd, Moscow 117246, Russia. Phone: 7 (095) 332-3435. Fax: 7 (095) 331-0101. E-mail: Biotec{at}glas.apc.org.


Antimicrobial Agents and Chemotherapy, November 1998, p. 2841-2847, Vol. 42, No. 11
0066-4804/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Firsov, A. A., Lubenko, I. Y., Vostrov, S. N., Portnoy, Y. A., Zinner, S. H. (2005). Antistaphylococcal Effect Related to the Area under the Curve/MIC Ratio in an In Vitro Dynamic Model: Predicted Breakpoints versus Clinically Achievable Values for Seven Fluoroquinolones. Antimicrob. Agents Chemother. 49: 2642-2647 [Abstract] [Full Text]  
  • Mueller, M., de la Pena, A., Derendorf, H. (2004). Issues in Pharmacokinetics and Pharmacodynamics of Anti-Infective Agents: Kill Curves versus MIC. Antimicrob. Agents Chemother. 48: 369-377 [Full Text]  
  • Schentag, J. J, Meagher, A. K, Forrest, A. (2003). Fluoroquinolone AUIC Break Points and the Link to Bacterial Killing Rates: Part 1: In Vitro and Animal Models. The Annals of Pharmacotherapy 37: 1287-1298 [Abstract] [Full Text]  
  • Zhanel, G. G, Noreddin, A. M (2003). Fluoroquinolone AUIC Break Points and the Link to Bacterial Killing Rates: In Vitro Models. The Annals of Pharmacotherapy 37: 1331-1334 [Full Text]  
  • Bakker-Woudenberg, I. A. J. M., ten Kate, M. T., Guo, L., Working, P., Mouton, J. W. (2002). Ciprofloxacin in Polyethylene Glycol-Coated Liposomes: Efficacy in Rat Models of Acute or Chronic Pseudomonas aeruginosa Infection. Antimicrob. Agents Chemother. 46: 2575-2581 [Abstract] [Full Text]  
  • Zinner, S. H., Firsov, A. A., Gilbert, D., Simmons, K., Lubenko, I. Yu. (2001). The pharmacodynamics of gatifloxacin and ciprofloxacin for pneumococci in an in vitro dynamic model: prediction of equiefficient doses. J Antimicrob Chemother 48: 821-826 [Abstract] [Full Text]  
  • Bakker-Woudenberg, I. A. J. M., ten Kate, M. T., Guo, L., Working, P., Mouton, J. W. (2001). Improved Efficacy of Ciprofloxacin Administered in Polyethylene Glycol-Coated Liposomes for Treatment of Klebsiella pneumoniae Pneumonia in Rats. Antimicrob. Agents Chemother. 45: 1487-1492 [Abstract] [Full Text]  
  • Firsov, A. A., Lubenko, I. Yu., Vostrov, S. N., Kononenko, O. V., Zinner, S. H., Portnoy, Y. A. (2000). Comparative pharmacodynamics of moxifloxacin and levofloxacin in an in vitro dynamic model: prediction of the equivalent AUC/MIC breakpoints and equiefficient doses. J Antimicrob Chemother 46: 725-732 [Abstract] [Full Text]  
  • Delacher, S., Derendorf, H., Hollenstein, U., Brunner, M., Joukhadar, C., Hofmann, S., Georgopoulos, A., Eichler, H. G., Muller, M. (2000). A combined in vivo pharmacokinetic-in vitro pharmacodynamic approach to simulate target site pharmacodynamics of antibiotics in humans. J Antimicrob Chemother 46: 733-739 [Abstract] [Full Text]  
  • MacGowan, A., Rogers, C., Bowker, K. (2000). The use of in vitro pharmacodynamic models of infection to optimize fluoroquinolone dosing regimens. J Antimicrob Chemother 46: 163-170 [Full Text]  
  • Odenholt, I., Cars, T., Lowdin, E. (2000). Pharmacodynamic studies of trovafloxacin and grepafloxacin in vitro against Gram-positive and Gram-negative bacteria. J Antimicrob Chemother 46: 35-43 [Abstract] [Full Text]  
  • Vostrov, S. N., Kononenko, O. V., Lubenko, I. Y., Zinner, S. H., Firsov, A. A. (2000). Comparative Pharmacodynamics of Gatifloxacin and Ciprofloxacin in an In Vitro Dynamic Model: Prediction of Equiefficient Doses and the Breakpoints of the Area under the Curve/MIC Ratio. Antimicrob. Agents Chemother. 44: 879-884 [Abstract] [Full Text]