Removal of Doripenem During Hemodialysis and the Optimum Dosing Regimen for Patients Undergoing Hemodialysis

The removal of doripenem by hemodialysis was studied in six hemodialysis patients. Following an intravenous drip infusion of 0.5 g of doripenem, plasma concentrations of the drug were measured. The decrease in drug concentrations in plasma was observed during various periods of non-hemodialysis, and hemodialysis accelerated the elimination of doripenem. For example, the calculated mean half-life during hemodialysis was significantly shorter than that during non-hemodialysis periods (P = 0.002). The calculated pharmacokinetic parameters indicated that the mean rate of decrease in plasma concentration due to hemodialysis alone was 56.12 +/- 8.11%. Upon obtaining these results and several pharmacokinetic parameters, we attempted to optimize the dosing regimen of doripenem for hemodialysis patients. We recommend the use of 0.25 g of doripenem once a day in patients infected with viable bacteria, and in patients who are infected with Pseudomonas aeruginosa, 0.5 g twice a day on the first day of administration, followed by 0.5 g once a day.