Many people in our R&D group have a long history with the development of novel chemistries for use in real-time PCR. A couple of people on staff were involved with the invention of the minor groove binder, which is used in the stability of PCR reactions and specificity. Our patents cover many of these technologies, and we are looking for opportunities to develop new assays. We recently released high-throughput hepatitis D virus and John Cunningham virus and norovirus 1 and 2 assays, and we’ll soon release high-throughput hepatitis A virus and Legionella assays and lower-throughput HDV and human herpes virus 7. Coming soon are mycoplasma, ureaplasma, measles, and parvovirus B19.
You must have been pleased by the court’s decision on the FDA’s proposed regulation of laboratory-developed tests.
Scott Johnston: Yes, we are relieved but also excited because now we can continue to work on the assays and technologies we’ve been developing for the laboratory.
Steve, many people may think LDTs are for small or niche labs or for large reference and academic labs. Do your customers span the spectrum of lab types and areas?
Steve Swartzell: Yes. We provide tests for clinical reference labs. Many of our primary customers are children’s hospitals and regional medical centers that serve a particular area and are often associated with an educational institution.
Has ELITech molecular diagnostics played a role in developing LDTs for children’s hospitals?
Scott Johnston: Yes, we’ve worked for many years with partner groups that are testing laboratories to develop different assays.
Steve, can you discuss selecting the correct assay for a specific disease when developing an LDT?
Steve Swartzell: Let’s use the example of transplant patients. One of the most critical tests for viral load testing is BK virus, so we provide that test as an ASR. We also have tests for cytomegalovirus and Epstein-Barr virus, which are also implicated in transplant patients. If it’s for a respiratory virus, we work with labs to provide the test and help with validation.
Labs with FDA-approved tests have to validate those tests in their own setting. What are the validation challenges in labor and process for LDTs?
Steve Swartzell: Labor is a big part of it. Having lab personnel who are capable of doing the validation and understand what it takes to make sure the test is functioning properly is a challenge. Many people who do validations have other duties also—they’re doing live testing at the same time they’re doing validations, so that can be a challenge. Getting positive samples of what you’re trying to validate is another hurdle, because you have to test actual patient samples.
Do you help labs with sample exchange?
Steve Swartzell: We can help to an extent. We can put the labs that want to validate a test in touch with customers who are already using the test, and we’ve had good luck doing that. Getting samples for esoteric tests can be difficult, but we can guide our customers to where they should go to get the samples they need.
Scott, what drives the decision for a laboratory to choose an LDT versus an IVD when there is an IVD-approved test?
Scott Johnston: If there is an IVD and the lab wants to do an LDT, it may be a matter of flexibility. Some IVDs are set up for a higher-throughput environment than is right for the lab. Some customers are using platforms with IVDs that run thousands of samples. If the lab doesn’t get that many in a given month, it may be more cost-effective to run an LDT than an IVD for the same disease state. It’s more work in terms of validation, but it gives the lab more flexibility in terms of volume.