[by Christina Chew] It is increasingly common to test in panels to gain clarity on disease while treatment will be most effective. Numerous multiplex products are on the market, and their effectiveness has been shown in studies, but there are challenges with reimbursement. In this article, we will look at the current status of syndromic testing. Syndromic and other microbiology diagnostic markets are covered in our report The Worldwide Microbiology Market (Traditional Microbiology, Microbiology/Infectious Disease Immunoassays, Molecular Microbiology, Mass Spectrometry in Microbiology)
“With these FDA clearances and new tests being introduced over the last decade, companies are placing bets on syndromic testing taking off. Siemens Healthineers, for example, is betting that syndromic testing will boost its diagnostics franchise by acquiring Luxembourg-based Fast Track Diagnostics in 2018.”
Since the discovery of duplex DNA in 1953 by Watson and Crick, the diagnostics area has witnessed tremendous growth in the field of molecular diagnostics, particularly in areas such as improved sensitivity, versatility of technology and automation. In the past decade, molecular diagnostics has resulted in a paradigm shift in clinical practice by enabling rapid detection of pathogens in blood cultures, respiratory specimens, stool, etc. During this time, we have also witnessed the launch of a single molecular test, such as the Abbott ID NOW (formerly Alere i) to a multiplex molecular panels with more than five targets, such as the FilmArray Blood Culture Identification (BCID) panel by BioFire Diagnostics, LLC (a Biomerieux company). This revolutionary multiplex tests enable rapid diagnosis of certain infections thus allowing healthcare providers make clinical management decisions in a timely manner.
The word syndromic comes from the root syndrome meaning a set of medical signs and symptoms that are correlated with each other or with a specific health-related cause. Often, patients can present with symptoms that are non-specific, but a combination of them can suggest certain diagnoses.
There have been a number of multiplex respiratory panels that can detect 5 or more pathogens simultaneously that have been FDA cleared. Upper respiratory infection is very common and afflicts millions of people in the US each year. It is the most cited reason for doctors’ visits. The first multiplex panel to receive FDA clearance was the Luminex xTAG RVP v1, which received clearance in 2008. This was followed by the Luminex xTAG-RVP Fast clearance three years later. They test 12 and 8 targets, respectively, with turnaround time of 8 and 6 hours. The NxTAG RPP (Luminex), which was cleared in 2015 can detect 20 pathogens at once with a turnaround time of 4 hours. GenMark Diagnostics’ eSensor RVP assay is performed on the XT-8 system and targets 14 pathogens with a turnaround time of 8 hours. Of all the commercialized respiratory multiplex tests, BioFire’s FilmArray respiratory panel (FA-RP) provides results in an hour, the fastest among its competitors.
Another growing infectious disease multiplex molecular test is in the gastrointestinal (GI) area. Conventional test methods for GI pathogens, such as culture, antigen tests and microscopic exams are not only time consuming but also costly and have limited sensitivity. According to the World Gastroenterology Organization, there are 2 billion new cases annually, resulting in 1.9 billion deaths among children under 5 years old. And according to the Centers for Disease Control and Prevention (CDC), GI illnesses account for 76 million emergency department (ED) visits and hospitalizations in the US each year. The severity of foodborne illnesses makes the case for faster and more sensitive molecular tests.
There are three FDA cleared multiplex assays that can detest more than 5 stool pathogens – xTAG GI pathogen panel and Verigene Enteric Pathogens by Luminex and BioFire FilmArray GI panel from BioFire. A study conducted at the University of Texas Medical Branch found that the BioFire FilmArray GI panel improved patient care due to its ability to identify a broad range of pathogens in an hour, allowing for proper treatment while reducing the need for further diagnostic tests and hospitalization. The authors also found that overall health care cost could have been reduced by almost $300 per patient if the FilmArray GI panel was used. This study definitely makes a compelling case for the need of GI multiplex syndromic tests.
With these FDA clearances and new tests being introduced over the last decade, companies are placing bets on syndromic testing taking off. Siemens Healthineers, for example, is betting that syndromic testing will boost its diagnostics franchise by acquiring Luxembourg-based Fast Track Diagnostics in 2018. Siemens Healthineers currently does not have commercialized molecular tests for infectious diseases. Fast Track Diagnostics (FTD) offers a wide range of tests, such as respiratory, GI, STI, and touts its capability to distinguish between viral or bacterial infection in one test. So far, FTD has not received FDA clearances for its tests yet.
However, reimbursement remains a challenging topic with syndromic multiplex testing. Multiplex assays are assigned various billing codes related to the number of targets in the tests. However, in late 2018, Palmetto deemed the multiplex viral panels do not meet Medicare’s “reasonable and necessary” criteria. Palmetto also stated that there is a lack of clinical utility when it comes to rapid and sensitive nucleic acid testing in decreasing the use of antibiotics. Finally, the Medicare contractor determined that syndromic surveillance isn’t part of Medicare benefits. This is a set back for syndromic testing. It may take years of clinical studies to prove the clinical utility and ROI of syndromic tests to gain a reversal of this decision.
Syndromic multiplex testing is relatively new to the market and is performed in a clinical microbiology setting. It is anticipated that it will become increasingly common over time and can be used in point-of-care settings. Given that reimbursement is a challenge, it may not be adopted as readily as many had hoped. The long turnaround time, lack of flexibility in some panels and cost considerations may delay POC adoption. Kalorama’s prediction of growth in the molecular POC space hasn’t materialized. Until the reimbursement challenges is resolved, growth in syndromic molecular multiplex testing could be slowed.