Pharmacokinetics of anidulafungin in critically ill patients with candida peritonitis

Summary An adequate understanding of the concentrations reached in peritoneal fluid (PF) by an antifungal agent in patients suspected of suffering from peritoneal infection is of great interest to ensure that therapeutic levels are achieved within the peritoneal cavity. To this end, a study was conducted on 31 patients with suspected fungal infection of the abdominal cavity. Patients were treated with the conventional dose of anidulafungin (initial 200 mg loading dose and 100 mg every 24 h thereafter). Venous blood and peritoneal fluid samples were collected on the second day of treatment. The mean area under the curve (AUC) in PF was 30% of that determined in the plasma. No patient experienced adverse effects. Objective To describe the pharmacokinetic (PK) of anidulafungin and to evaluate its concentration in the Peritoneal Fluid (PF) of patients suspected of suffering from peritoneal infection undergoing abdominal surgery, to ensure that therapeutic levels are achieved within the peritoneal cavity. Design/Methods Descriptive, open, prospective, observational, multicentre and non-interventional study. Anidulafungin at conventional doses were used. Blood and PF samples were obtained on day 2 of treatment or on any of the following days. Results A total of 31 patients were included in the study with a serious clinical situation, as demonstrated by high mean clinical severity scales APACHE II (15) and SOFA (16). The mean area under the curve (AUC) in PF was 30% (31 ± 19) of that determined in the plasma and maximum concentration (Cmax) reached in PF (mg/l) close to 1 (0.9 ± 0.5). No adverse effects were observed in any of the 31 patients. Conclusions Anidulafungin at conventional doses reaches PF concentrations that exceed the MIC of the usual Candida spp, which explains the proven efficacy of this echinocandin in the treatment of Candida peritonitis in critically ill patients.