Rapid Low Cost Phenotypic Antibiotic Susceptibility Testing

Project Summary The rise and spread of antimicrobial-resistant (AMR) infection now makes it increasingly vital to speed the availability of phenotypic susceptibility test results. In the case of AMR organisms, the broad- spectrum antimicrobial therapy used to protect patients during the 2 day period required for growth of colonies and performance of overnight automated susceptibility testing (AST) methods is, increasingly, too long to wait to identify an effective therapeutic agent, especially in the case of fast moving and deadly blood infection, or other time-sensitive clinical samples, such as elderly ICU UTI’s, pediatric, and cerebrospinal fluid samples. Specific Diagnostics Reveal™ AST system delivers phenotypic AST results in ≈5 hours, both directly from positive blood culture samples as well as from time-sensitive isolate dilutions, allowing same-shift modification of antibiotic therapy. The system is based on the use of proprietary, disposable, low cost small molecular sensor (SMS) array highly sensitive to the volatiles emitted by microorganisms during their growth. By attaching a sheet of such sensor arrays to a multi-well dried antibiotic plates, the system detects growth and calls MIC with the same robust accuracy as the turbidity-based broth microdilution gold standard, but directly from a diluted positive blood culture sample, and in 5 hours. The Reveal system’s inherent simplicity enables a comparatively low-cost instrument and disposable, enabling plausibly broad adoption and consequently significant impact on both patient outcome and health care system cost and performance. Specific Diagnostics has met or exceeded all the objectives defined in the Phase 2 NIAID SBIR grant, which included characterization of the system, development of a prototype RUO version, and the engineering and manufacture of the alpha version of the commercial instrument. In October of 2018, Specific attended a pre-sub meeting at FDA, receiving guidance defining the protocols required for clinical studies to demonstrate the accuracy and reliability of the Reveal assay with both positive blood culture and isolate dilution samples. Under the requested Phase IIB, the proposal’s 9 objectives include completion of a quality system, ISO- 13485:2016 certification for our development and manufacturing processes, the conduct of clinical studies at 3 sites, along with the analytical studies and reference lab confirmatory reference method assays to enable confirmation of Reveal performance per FDA requirements, followed by successful 510(k) submittal and clearance, allowing the clinical use of the Reveal system during the last year of the grant.