Pharmacokinetics of anidulafungin in critically ill patients with Candida peritonitis

To describe the pharmacokinetic (PK) profile of anidulafungin and to evaluate its concentration in the peritoneal fluid (PF) of patients suspected of suffering from peritoneal infection undergoing abdominal surgery, in order to ensure that therapeutic levels are achieved within the peritoneal cavity.

A descriptive, open, prospective, observational, multicentre and non-interventional study was performed. Anidulafungin was used at conventional doses. Blood and PF samples were obtained on day 2 of treatment or on any of the following days.

A total of 31 patients in a serious clinical condition, as demonstrated by high mean clinical severity scale scores (APACHE II and SOFA scores), were included in the study. The mean area under the curve (AUC) in PF was 30% (31±19%) of that determined in the plasma and the maximum concentration (Cmax) reached in PF (mg/l) was close to 1 (0.9±0.5). No adverse effects were observed in any of the 31 patients.

Anidulafungin at conventional doses reaches PF concentrations that exceed the minimum inhibitory concentration of the usual Candida spp, which explains the proven efficacy of this echinocandin in the treatment of Candida peritonitis in critically ill patients.