Pharmacokinetics of ganciclovir in a patient undergoing chronic haemodialysis

The pharmacokinetics of ganciclovir was evaluated in a 73-year old anuric, haemodialyzed patient given 1.25 mg·kg^-1 at the end of each haemodialysis session, three times per week.A biexponential decrease in plasma ganciclovir was observed, with a peak concentration of 3.7 mg·1^-1 followed by a steady state value of 2.6 mg·1^-1 for almost 40 h. The total plasma clearance was 0.05 ml·min^-1·kg^-1, the volume of distribution at steady state was 0.61·kg^-1, the elimination half life was 132 h, the area under curve was 372 g·h·ml^-1, the mean residence time was 190 h, and the percentage of ganciclovir cleared from plasma after a 5 h haemodialysis session was 52.1%.The simulated pharmacokinetics over one month, following the same scheme of administration, did not suggest marked accumulation of ganciclovir. These results were obtained after a reduction of 58% in the recommended dose in patients with impaired renal function.