Efficacy and Safety of Vancomycin Bayesian-Estimated Area Under the Curve Versus Trough-Based Dosing

Background: Vancomycin guidelines by the Infectious Diseases Society of America and American Society of Health-System Pharmacists endorse Bayesian-software-assisted area under the curve (AUC 24h ) in their 2020 update. At this time, there are limited clinical data that support its use. Objectives: The purpose of this study is to evaluate the safety benefits and efficacy outcomes of using Bayesian-assisted AUC 24h dosing compared to trough dosing. Methods: Hospitalized patients from before February 1, 2020, (preimplementation of AUC 24h dosing) and after August 1, 2020, (postimplementation) were reviewed. Patients with confirmed or suspected methicillin-resistant Staphylococcus aureus (MRSA) infection of the lungs, heart, bones, prosthetic joint, or blood receiving vancomycin for at least 72 hours were included. The primary endpoint was the percentage of patients experiencing an acute kidney injury (AKI) in the trough-based group versus those experiencing AKI in the AUC 24h group. The composite of all-cause mortality, 30-day readmission, or change in antibiotic therapy due to clinical worsening in patients with confirmed MRSA infections was included as a secondary endpoint. Data were analyzed with statistical testing methods as appropriate. Results: There was a significant reduction in AKI between the AUC 24h dosing and trough dosing groups (3% vs 12%; P < 0.01). The efficacy for MRSA infections was also similar between groups (11% vs 14%; P = 0.72). Conclusion and Relevance: Bayesian-assisted AUC 24h dosing was associated with a significant reduction in incidence of AKI when compared to trough-based dosing. There was no difference in the composite efficacy endpoint for patients with confirmed MRSA infection, although the study was not powered for this analysis. These data may provide evidence for more institutions to adopt the Bayesian software to assist in dosing of vancomycin.