Meta-pharmacokinetic analysis of posaconazole following dosing of oral suspension, delayed-release tablet, and intravenous infusion in patients vs. healthy volunteers: Impact of clinical characteristics and race.

OBJECTIVES

To investigate the potential impact of clinical characteristics and the Chinese race on posaconazole pharmacokinetics in patients using an integrated population pharmacokinetic model for posaconazole oral suspension (SUS), delayed-release tablet (DR-tablet), and intravenous (IV) infusion that was developed in healthy volunteers (HV).

METHODS

1046 concentrations from 105 prospectively studied Caucasian patients receiving either of the three posaconazole formulations were pooled with 3898 concentrations from 182 HV. Clinical characteristics were tested for significance. The impact of Chinese race was assessed using 292 opportunistic samples from 80 Chinese patients receiving SUS.

RESULTS

Bioavailability of SUS (F) in patients decreased from 38.2% to 24.6% when the dose was increased from 100 mg to 600 mg. Bioavailability of DR-tablet (F) was 59% regardless of dose. Mucositis, diarrhoea, administration through a nasogastric tube, and concomitant use of proton pump inhibitors or metoclopramide reduced F by 61%, 36%, 44%, 48%, and 29%, respectively, putting patients with these characteristics at increased risk of inadequate exposure. Clearance decreased from 7.0 to 5.1 L/h once albumin levels were <30 g/L. Patients showed an 84.4% larger peripheral volume of distribution (V) and 67.5% lower intercompartmental clearance (Q) compared with HV. No racial difference could be identified.

CONCLUSIONS

Pharmacokinetics of posaconazole in patients differ considerably to those in HV, with altered F that is also impacted by clinical covariates, an F similar to fasted conditions in HV, and altered parameters for clearance, V, and Q. There was no evidence to indicate that Chinese patients require a different dose to Caucasian patients.