The Food and Drug Administration could prove an impediment to portable coronavirus screening tests, testing advocates fear.
Many biotech companies are developing portable tests that can be used at work or at home. But they must go through the FDA’s approval process and meet agency standards. Currently, the FDA requires a point-of-care test, a test taken at a hospital or clinic and processed in a lab, to achieve 80% accuracy for approval. It is not clear whether the FDA will apply that standard to portable tests.
“A cautious, risk-averse FDA with an exponentially growing virus — that is a recipe for disaster, and that is exactly what has happened,” said Alex Tabarrok, an economist at George Mason University. “The FDA, as usual, following their standard operating procedure, has been very slow, and I think that has impeded testing right from day one.”
The FDA approval process is often lengthy in regular times, but the time cost of waiting for approval is extraordinarily higher in the context of a pandemic. And there is the possibility that a test that is not 80% accurate never becomes available because the FDA will not approve.
“In the time of a pandemic, the FDA has to make a tough decision,” said Dr. Peter Pitts, president of the conservative Center for Medicine in the Public Interest and a former associate commissioner at the FDA. “In a perfect world, the best number is the highest degree of accuracy achievable, but I don’t think we can allow the perfect to get in the way of the good.”
Pitts added that it is important for public confidence that tests be reliable.
Yet Tabarrok thinks the FDA should simply get out of the way.
“What the FDA could do is verify and document what standards the tests are meeting,” he said. “But otherwise, allow these tests to get on the market as quickly as possible.”
There are solid reasons for getting portable tests to market quickly.
If affordable, they would enable people to test themselves on a regular basis. That could prove pivotal for reopening business and schools, as workers and children who are infected with the virus would know to remain home.
It could also relieve the pressure on the labs processing point-of-care tests. Many of those labs are overburdened, often taking a week or more to return results. Sonora Quest, the lab company that analyzes the tests in Arizona, for example, has a backlog of over 61,000 tests. This has led to 10 to 14 day turnaround times, often causing the results to be outdated.
“That’s essentially useless,” said Tabarrok. “If you think you have COVID, and you have to wait two weeks to get test results, and in that two weeks you are spreading the virus, then having a test is almost pointless.”
Portable tests are generally less accurate than point-of-care tests because they are less likely to detect low levels of the coronavirus. But that may not matter much since a person with low levels of the virus is not likely to be contagious.
“Screening devices, if they are good, pick up high viral loads,” said Carlos-Henri Ferre, senior associate of operations and communications at E25Bio, a Massachusetts-based startup. “That means someone is a superspreader [of the virus] at that point.”
Testing regularly increases the odds that a person will know if he or she is a superspreader.
E25Bio has developed a portable test that is ready for FDA approval. It involves putting a nasal swab on a test strip. The results are ready in 15 minutes. Eventually, Ferre wants it to be available for use at home on a daily basis.
BioFrontiers Institute at the University of Colorado at Boulder has also developed a relatively simple test that only requires the patient to spit in a small tube and produces a result in about 45 minutes. It could be used at factories or schools.
Roy Parker, director of BioFrontiers, coauthored a paper showing that effective surveillance of the pandemic is heavily dependent on the frequency of testing. By contrast, the accuracy of testing only marginally improves surveillance.
Ferre said that regular testing is the best way to ensure that someone who is contagious knows that he or she is infected.
“If we can collectively agree that we need a device that screens almost daily, I think we’ll be in a better place,” he said. “You may miss [the infection] one day, but you will be catching it at the point when a person is most likely to spread it.”
A spokesperson for the FDA said the agency would be looking at the total package when examining each application from a company seeking approval of a coronavirus test. The spokesperson said that the availability of a test would be weighed against its accuracy.
When asked if the 80% standard made sense for E25Bio’s test, Ferre replied, “We’re not commenting on our studies right now as we are finalizing them … we think that frequency [of testing] is the most important thing in this case.”
