Pharmacokinetic / pharmacodynamic relationships of liposomal amphotericin b and miltefosine in experimental visceral leishmaniasis Articles uri icon

authors

  • Voak, Andrew A.
  • Harris, Andy
  • Coteron Lopez, Jose Miguel
  • FERRER BAZAGA, SANTIAGO
  • Angulo Barturen, Iñigo
  • Croft, Simon L.
  • Seifert, Karin

publication date

  • March 2021

start page

  • 1

end page

  • 16

issue

  • 3

volume

  • 15

International Standard Serial Number (ISSN)

  • 1935-2727

Electronic International Standard Serial Number (EISSN)

  • 1935-2735

abstract

  • Background There is a continued need to develop effective and safe treatments for visceral leishmania-sis (VL). Preclinical studies on pharmacokinetics and pharmacodynamics of anti-infective agents, such as anti-bacterials and anti-fungals, have provided valuable information in the development and dosing of these agents. The aim of this study was to characterise the phar-macokinetic and pharmacodynamic properties of the anti-leishmanial drugs AmBisome and miltefosine in a preclinical disease model of VL. Methodology / Principal findings BALB/c mice were infected with L. donovani (MHOM/ET/67/HU3) amastigotes. Groups of mice were treated with miltefosine (orally, multi-dose regimen) or AmBisome (intravenously, single dose regimen) or left untreated as control groups. At set time points groups of mice were killed and plasma, livers and spleens harvested. For pharmacodynamics the hepatic parasite burden was determined microscopically from tissue impression smears. For phar-macokinetics drug concentrations were measured in plasma and whole tissue homogenates by LC-MS. Unbound drug concentrations were determined by rapid equilibrium dialysis. Doses exerting maximum anti-leishmanial effects were 40 mg/kg for AmBisome and 150 mg/kg (cumulatively) for miltefosine. AmBisome displayed a wider therapeutic range than miltefosine. Dose fractionation at a total dose of 2.5 mg/kg pointed towards concentration-dependent anti-leishmanial activity of AmBisome, favouring the administration of large doses infrequently. Protein binding was >99% for miltefosine and amphotericin B in plasma and tissue homogenates. Conclusion / Significance Using a PK/PD approach we propose optimal dosing strategies for AmBisome. Additionally, we describe pharmacokinetic and pharmacodynamic properties of miltefosine and compare our findings in a preclinical disease model to available knowledge from studies in humans. This approach also presents a strategy for improved use of animal models in the drug development process for VL.

subjects

  • Biology and Biomedicine