Focus Diagnostics Receives FDA Clearance for Moderate Complexity Simplexa® HSV MDx

Quest Diagnostics announced that its Focus Diagnostics products business has received expedited FDA 510(k) clearance and CLIA moderate complexity categorization for its new Simplexa HSV 1 & 2 Direct molecular test on the 3M Integrated Cycler. The test, which is now available for purchase in the United States, is the first molecular test to be cleared by the FDA for the qualitative detection and differentiation of herpes simplex virus 1 (HSV-1) and herpes simplex virus 2 (HSV-2) in cerebrospinal fluid (CSF) from patients suspected of HSV central nervous system (CNS) infection, including encephalitis. 

Encephalitis is an inflammation of the brain often caused by the herpes simplex or other viruses. The Infectious Diseases Society of America (IDSA) recommends herpes simplex PCR testing on all CSF specimens in patients with encephalitis.  HSV encephalitis occurs in all ages and during all seasons, with HSV-1 encephalitis more common in adults and HSV-2 encephalitis more common in newborn infants. Accurate determination of the virus causing encephalitis can influence treatment decisions and outcomes.

The moderate complexity categorization of the Simplexa HSV 1 & 2 Direct molecular test significantly broadens the potential clinical access to the technology. Moderate complexity laboratories, defined by the Clinical Laboratory Improvement Amendments (CLIA), include certain types of physician’s offices, community hospitals, health clinics and integrated delivery networks. These facilities typically lack the personnel and technology to perform high complexity molecular diagnostic tests. Since the test can be performed in these moderate complexity labs, patient results may be obtained readily to help speed therapeutic decisions.

"Diagnosing encephalitis is a major health challenge because determining the virus causing the condition shapes clinical decision making, yet most diagnostic tools, are slow to perform and may delay therapy,” said Kay Myrdal, Vice President and General Manager of Focus Diagnostics. “Our Simplexa HSV 1 & 2 Direct test’s ability to rapidly detect and distinguish HSV 1 & 2 in the spinal fluid of a patient suspected of suffering from encephalitis is critically important to clinical treatment decisions. This new assay is an important step in innovations that bring diagnostic insights closer to the patient, to help promote better care and outcomes.”

Simplexa tests, designed for use on the 3M™ Integrated Cycler, employ real-time polymerase chain reaction (PCR) technology to detect DNA or RNA in viruses, bacteria, and other analytes. Simplexa HSV 1 & 2 Direct is intended to aid in the diagnosis of HSV central nervous system (CNS) infection using CSF from patients suspected of HSV infections of the CNS. Simplexa tests use a proprietary chemistry that eliminates the need for nucleic acid extraction, which involves purifying nucleic acids from a specimen.  Nucleic acid extraction is an expensive and time-consuming process requiring specialized equipment and trained personnel.

“The nucleic acid extraction process, used in most commercial molecular test kits, can add approximately 60 to 90 minutes to the total time to result. Focus Diagnostics replaced the extraction process in our Simplexa products with a proprietary chemistry and technology,” said Michelle Tabb, Ph.D, Vice President, Research and Development for Focus Diagnostics. “Simplexa HSV 1 & 2 Direct results, like those of other Simplexa Direct test products, are available in about an hour from receiving a specimen for testing. This is a major advantage when dealing with an acute neurological condition like encephalitis.”

Simplexa HSV 1 & 2 Direct showed strong performance in clinical studies, with 100% and 98% sensitivity for detection of HSV-1 and HSV-2 respectively. The test was CE marked for distribution to more than 30 countries in Europe in November 2013.