Evaluation of teicoplanin dosing designs to achieve a new target trough concentration

Minimum inhibitory concentration (MIC) creep in vancomycin has prompted guidelines that recommend a target trough concentration (C _min) of 15–20 mg/L, and it is also considered necessary to set a C _min of >15 mg/L for teicoplanin (TEIC), especially in patients with complicated methicillin-resistant Staphylococcus aureus (MRSA) infections. The aim of this study was to investigate the appropriate TEIC regimen for reaching the revised target C _min (15–30 mg/L) in patients with normal renal function and those with renal dysfunction. We analyzed patients with MRSA infections who were treated with TEIC between July 2006 and December 2009. Two-day loading regimen was studied in patients with non-renal-dysfunction (group 1). The 1-day loading regimen was studied in patients with non-renal-dysfunction (group 2, control) and in patients with renal dysfunction (group 3). The 178 patients in the study consisted of 76, 28, and 74 patients in groups 1, 2, and 3, respectively. C _min on day 4 was 14.6 ± 5.6, 11.9 ± 4.1, and 13.5 ± 4.2 mg/L, and the proportion of patients achieving the revised target range was 34.2%, 17.9%, and 20.3%, respectively. Only one patient in group 1 revealed C _min of >30 mg/L. Treatment success rates, nephrotoxicity, and hepatotoxicity were similar among the three groups. It was difficult to achieve the revised target C _min with the 2-day loading regimen in patients without renal dysfunction and with the standard TEIC regimen, even in patients with renal dysfunction. Further investigation of an even higher TEIC dosing regimen is considered necessary.