IngentaConnect The effect of fluconazole on ritonavir and saquinavir pharmacokin...

Authors: Koks, C. H. W.¹; Crommentuyn, K. M. L.¹; Hoetelmans, R. M. W.¹; Burger, D. M.²; Koopmans, P. P.³; Mathôt, R. A. A.¹; Mulder, J. W.⁴; Meenhorst, P. L.⁴; Beijnen, J. H.¹

Source: British Journal of Clinical Pharmacology, Volume 51, Number 6, June 2001 , pp. 631-635(5)

Publisher: Blackwell Publishing

Abstract:

Aims

To study the effect of fluconazole on the steady-state pharmacokinetics of the protease inhibitors ritonavir and saquinavir in HIV-1-infected patients. Methods

Five subjects treated with saquinavir and three with ritonavir received the protease inhibitor alone (saquinavir 1200 mg three times daily, ritonavir 600 mg twice daily) on day 1, and the same protease inhibitor in combination with fluconazole (400 mg on day 2 and 200 mg on days 3 to 8). Pharmacokinetic parameters were determined on days 1 and 8. Results

In the saquinavir group, the median increase in the area under the plasma concentration vs time curve was 50% from 1800 µg l⁻¹ h to 2700 µg l⁻¹ h (P = 0.04, median increase: 900 µg l⁻¹ h; 2.5 and 97.5 percentile: 500-1300), and 56% for the peak concentration in plasma (from 550 to 870 µg l⁻¹, P = 0.04; median increase: 320 µg l⁻¹ h, 2.5 and 97.5 percentile: 60-450 µg l⁻¹). In the ritonavir group, there were no detectable changes in the pharmacokinetic parameters on addition of fluconazole. Conclusions

Because of the favourable safety profile of saquinavir, dose adjustments are probably not necessary with concomitant use of fluconazole, as is the case for ritonavir.

Keywords: drug interaction; fluconazole; HIV-1 infection; ritonavir; saquinavir

Document Type: Research article

DOI: 10.1046/j.0306-5251.2001.01409.x

Affiliations: 1: Department of Pharmacy and Pharmacology, Slotervaart Hospital, Amsterdam, 2: Department of Clinical Pharmacy, Nijmegen University Hospital, Nijmegen, 3: Department of Internal Medicine, Nijmegen University Hospital, Nijmegen and 4: Department of Internal Medicine, Slotervaart Hospital, Amsterdam, The Netherlands

You have access to the full text article on a website external to Ingentaconnect.

Please click here to view this article on InterScience.

You may be required to register and activate access on InterScience before you can obtain the full text. If you have any queries please contact onlinehelp@oxon.blackwellpublishing.com

The effect of fluconazole on ritonavir and saquinavir pharmacokinetics in HIV-1-infected individuals