Population pharmacokinetics of oseltamivir and oseltamivir carboxylate in obese and non-obese volunteers

Br J Clin Pharmacol. 2016 Jun;81(6):1103-12. doi: 10.1111/bcp.12892. Epub 2016 Mar 4.

Abstract

Aims: The aims of the present study were to compare the pharmacokinetics of oseltamivir and its active antiviral metabolite oseltamivir carboxylate in obese and non-obese individuals and to determine the effect of obesity on the pharmacokinetic properties of oseltamivir and oseltamivir carboxylate.

Methods: The population pharmacokinetic properties of oseltamivir and oseltamivir carboxylate were evaluated in 12 obese [body mass index (BMI) ≥30 kg m(-2) ) and 12 non-obese (BMI <30 kg m(-2) ) Thai adult volunteers receiving a standard dose of 75 mg and a double dose of 150 mg in a randomized sequence. Concentration-time data were collected and analysed using nonlinear mixed-effects modelling.

Results: The pharmacokinetics of oseltamivir and oseltamivir carboxylate were described simultaneously by first-order absorption, with a one-compartment disposition model for oseltamivir, followed by a metabolism compartment and a one-compartment disposition model for oseltamivir carboxylate. Creatinine clearance was a significant predictor of oseltamivir carboxylate clearance {3.84% increase for each 10 ml min(-1) increase in creatinine clearance [95% confidence interval (CI) 0.178%, 8.02%]}. Obese individuals had an approximately 25% (95% CI 24%, 28%) higher oseltamivir clearance, 20% higher oseltamivir volume of distribution (95% CI 19%, 23%) and 10% higher oseltamivir carboxylate clearance (95% CI 9%, 11%) compared with non-obese individuals. However, these altered pharmacokinetic properties were small and did not change the overall exposure to oseltamivir carboxylate.

Conclusions: The results confirmed that a dose adjustment for oseltamivir in obese individuals is not necessary on the basis of its pharmacokinetics.

Keywords: influenza; obesity; oseltamivir; population pharmacokinetics.

Publication types

  • Controlled Clinical Trial

MeSH terms

  • Adolescent
  • Adult
  • Female
  • Humans
  • Male
  • Middle Aged
  • Models, Biological
  • Obesity / metabolism*
  • Oseltamivir / analogs & derivatives*
  • Oseltamivir / blood
  • Oseltamivir / pharmacokinetics*
  • Volunteers*
  • Young Adult

Substances

  • Oseltamivir
  • oseltamivir carboxylate