An AUC Target Simulation for Vancomycin in Patients With Class III Obesity.

Area of Science:

• Pharmacology
• Clinical Pharmacy
• Obesity Medicine

Background:

• Vancomycin is crucial for treating infections caused by Gram-positive bacteria.
• Determining optimal vancomycin dosing in class III obesity presents challenges due to altered pharmacokinetics.
• Current dosing strategies often rely on trough concentrations, which may not be sufficient for achieving therapeutic targets in obese patients.

Purpose of the Study:

• To compare 24-hour vancomycin dosage requirements between target area under the curve (AUC) and target trough approaches.
• To evaluate the implications of different vancomycin dosing strategies in patients with class III obesity.

Main Methods:

• A simulation was conducted using pharmacokinetic data from adult patients with class III obesity.
• The Sawchuck-Zaske method was used to calculate patient-specific pharmacokinetic parameters.
• Vancomycin 24-hour (Vanc24) dosages were simulated to achieve a target AUC of 400 mg/L·h and a target trough concentration of 15 mg/L.

Main Results:

• Sixty-three patients with class III obesity were included in the simulation.
• Mean Vanc24 dosage requirements were significantly lower with the target AUC approach (2783 mg) compared to the target trough approach (3995 mg) (P < .0001).
• Patients had a median BMI of 45.7 kg/m².

Conclusions:

• A target AUC approach necessitates lower vancomycin doses over 24 hours compared to a target trough approach in class III obesity.
• Implementing vancomycin therapeutic drug monitoring that targets AUC may decrease overall drug exposure.
• This strategy holds potential for reducing the risk of vancomycin-induced nephrotoxicity in obese patients.