MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12-64 µg/mL) (MicroScan)

The MicroScan Dried Gram-Negative MIC/Combo Panel with Cefepime is a laboratory antimicrobial susceptibility test used to determine whether gram-negative bacteria isolated from patient samples are susceptible or resistant to the antibiotic cefepime. Panels are rehydrated, inoculated with a bacterial suspension, incubated overnight at 35°C, and read either manually or with automated instruments to determine the minimum inhibitory concentration (MIC) of cefepime.

The proposed device uses the same overnight microdilution MIC susceptibility test technology as the predicate, with identical specimen type, incubation temperature (35°C ± 1°C), incubation atmosphere (aerobic), incubation time (16–20 hours), and reading methods (automated or manual). The only difference is the antimicrobial agent: cefepime at concentrations of 0.12–64 µg/mL versus ceftazidime at 0.5–64 µg/mL in the predicate.

The submission references the FDA document 'Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA' (August 28, 2009) and compares performance against a CLSI frozen Reference Panel as the gold standard.

Substantial equivalence is supported because the device uses identical microdilution MIC methodology, specimen preparation, incubation conditions, and reading methods as the predicate device. Performance studies demonstrate acceptable essential agreement (93.5–95.7%) and categorical agreement (90.3–96.3%) with CLSI reference panels across the three bacterial groups (Enterobacterales, Pseudomonas aeruginosa, and Aeromonas spp.). Reproducibility and quality control testing also yielded acceptable results. The only modification—substituting a different third-generation cephalosporin antibiotic in the same concentration format—does not fundamentally alter the device's principle of operation or safety/effectiveness profile.