Telavancin Pharmacokinetics and Pharmacodynamics in Patients with Complicated Skin and Skin Structure Infections and Various Degrees of Renal Function

Abstract

This study characterized the pharmacokinetic/pharmacodynamic profiles of the Food and Drug Administration (FDA)-approved telavancin renal dose adjustment schemes. A previously published two-compartment open model with first-order elimination and a combined additive and proportional residual error model derived from 749 adult subjects in 11 clinical trials was used to simulate the individual concentration-time profiles for 10,260 subjects (NONMEM). The dosing regimens simulated were 10 mg/kg of body weight once daily for individuals with creatinine clearances (CL(CR)s) of >50 ml/min, 7.5 mg/kg once daily for individuals with CL(CR)s of 30 to 50 ml/min, and 10 mg/kg every 2 days for those with CL(CR)s of <30 ml/min. The area under the concentration-time curve (AUC) under one dosing interval (AUC(τ)) was computed as dose/CL. The probability of achieving an AUC(τ)/MIC ratio of ≥ 219 was evaluated separately for each renal dosing scheme. Evaluation of the dosing regimens demonstrated similar AUC values across the different renal function groups. For all renal dosing strata, >90% of the simulated subjects achieved an AUC(τ)/MIC ratio of ≥ 219 for MIC values as high as 2 mg/liter. For patients with CL(CR)s of <30 ml/min, the probability of target attainment (PTA) exceeded 90% for both the AUC₀₋₂₄ (AUC from 0 to 24 h) and AUC₂₄₋₄₈ intervals for MICs of ≤ 1 mg/liter. At a MIC of 2 mg/liter, the PTAs were 89.3% and 23.6% for the AUC₀₋₂₄ and AUC₂₄₋₄₈ intervals, respectively. The comparable PTA profiles for the three dosing regimens across their respective dosing intervals indicate that the dose adjustments employed in phase III trials for complicated skin and skin structure infections were appropriate.