LIAISON PLEX Gram-Negative Blood Culture Assay

The LIAISON PLEX Gram-Negative Blood Culture Assay is an automated, multiplexed in vitro diagnostic test that detects and identifies gram-negative bacteria and antimicrobial resistance markers directly from positive blood culture bottles. It uses nucleic acid hybridization to simultaneously identify 18 gram-negative species/genera and 8 resistance markers (CTX-M, IMP, KPC, NDM, OXA, VIM, MCR, SME) to aid in diagnosis of bloodstream infections.

The LIAISON PLEX system is a fully automated sample-to-result platform using microarray-based hybridization without PCR amplification, performed on the LIAISON PLEX instrument. It differs from the predicate VERIGENE device primarily in expanded organism detection (18 vs. 8 organisms) and additional resistance markers (8 vs. 6), though both are automated multiplex nucleic acid assays on positive blood cultures using non-amplified hybridization approaches.

ISO 14971:2019 (risk management), ISO 62304:2006 (software lifecycle), ISO 13485:2016 (quality management), ISO 20916:2019 (clinical performance studies), IEC 62366-1:2015 (usability engineering), IEC 61010 series (electrical safety), EN ISO 18113 series (in vitro diagnostic labeling), CLSI EP12-A2 and EP25-A (analytical performance evaluation).

The candidate device is substantially equivalent to the VERIGENE BC-GN predicate because both are automated multiplex nucleic acid assays for gram-negative pathogen and resistance marker detection from positive blood cultures, using sample-to-result platforms with non-amplified hybridization detection. While the candidate offers expanded organism and resistance marker detection (a technological enhancement rather than fundamental change in principle), it achieves comparable or superior analytical and clinical performance: >96% sensitivity and >99% specificity across targets, 99.7% testing success rate, and demonstrated inclusivity across 246 on-panel organism strains and in silico validation. The intended use, patient population, sample type, and regulatory classification (Class II, 21 CFR 866.3365) are identical to the predicate.