FDA Clears First One-Day Susceptibility Test for MRSA/MSSA

MicroPhage, Inc., has received 510(k) clearance from the FDA to market its KeyPath™ MRSA/MSSA Blood Culture Test - BT, which returns same-day antibiotic susceptibility results for S. aureus infections.

The test is unique because it not only enables doctors to identify a S. aureus infection; it also determines whether the strain is methicillin resistant (MRSA) or methicillin susceptible (MSSA), thus providing the physician with the means to determine an effective course of treatment.

The test is the first product developed using MicroPhage's proprietary Bacteriophage Amplification Technology (BAT™) platform and meets stringent CLSI and FDA criteria. Unlike current test methods, which rely on lengthy culture procedures to isolate and characterize bacteria, BAT™ accelerates the process while exposing the bacteria to antibiotics, delivering true phenotypic antibiotic susceptibility results. The test requires only a few minutes of hands-on time and can be integrated into any laboratory immediately as no special instrumentation is required.

The KeyPath™ MRSA/MSSA Blood Culture Test - BT was evaluated in a clinical study of 1,116 blood samples at four major U.S. hospital centers, including Duke University Medical Center, UMDNJ-Robert Wood Johnson Medical School, Northwestern University and Denver Health. The test was 98.9 percent accurate (178/180) for MRSA identification and 99.4 percent accurate (153/154) in determining MSSA within the organisms identified as S. aureus.

'Other methods, such as PCR, mass spectrometry and immunoassays have been introduced but only provide bacterial identification and, in some cases, markers for antibiotic resistance,' said Drew Smith, Ph.D., Chief Science Officer at MicroPhage. 'However, these methods are affected by genetic mutations and other biological variables that can impact their accuracy. In contrast, the MicroPhage BAT™ platform provides a phenotypic result that directly assesses the organism's response to an antibiotic. The platform can be extended to a broad range of bacterial pathogens and sample types thus enabling development of a long pipeline of clinically useful susceptibility tests and test panels.'

The MicroPhage product pipeline includes rapid single-pathogen and multi-pathogen diagnostic tests for simultaneous detection and determination of antibiotic susceptibility. The KeyPath™ MRSA/MSSA Blood Culture Test - BT has already achieved CE marking and commercialization efforts are under way in Europe.