Background: Meropenem/Vaborbactam (MEV), a β-lactam combination antimicrobial consisting of meropenem, a carbapenem, and vaborbactam, a beta-lactamase inhibitor, is indicated for treatment of patients 18 years and older with complicated urinary tract infections (cUTI) including pyelonephritis caused by designated susceptible bacteria. In this study, the performance of VITEK® 2 AST-GN MEV with Enterobacteriaceae and Pseudomonas aeruginosa was evaluated against the CLSI broth microdilution (BMD) reference method.
Method: A total of 526 clinical and challenge isolates, including 449 Enterobacteriaceae and 77 Pseudomonas aeruginosa were tested by VITEK® 2 AST-GN MEV and BMD reference at four clinical trial sites. Results were analyzed for essential agreement (EA), category agreement (CA), major error (ME) and very major error (VME) rates following the ISO performance criteria (EA and CA ≥90%, ME and VME ≤3.0%) and using EUCAST breakpoints for Enterobacteriaceae and Pseudomonas aeruginosa (S ≤ 8µg/mL, I = N/A, R ≥ 16µg/mL).
Results: VITEK® 2 AST-GN MEV clinical trial performance is summarized below for Enterobacteriaceae and Pseudomonas aeruginosa. VITEK® 2 AST-GN MEV met the ISO susceptibility performance criteria for EA, CA, ME and VME, when applying EUCAST breakpoints.
*Minor errors (mE) are not applicable as there is no intermediate category.
Conclusions: When compared to the reference BMD method, results of this multi-center study support the acceptable performance of VITEK® 2 AST-GN MEV for determining the susceptibility of Enterobacteriaceae and Pseudomonas aeruginosa in a clinical setting.