The Food and Drug Administration, under criticism for allowing hundreds of antibody tests for the new coronavirus on the U.S. market without prior review, has imposed rigorous precision standards on commercial test companies and said it is cracking down on fraudulent actors.
At least 160 antibody tests for Covid-19 entered the U.S. market without previous FDA scrutiny on March 16, because the agency felt then that it was most important to get them to the public quickly. Accurate antibody testing is a potentially important tool for public-health officials assessing how extensively the coronavirus has swept through a region or state.
Now, the FDA will require test companies to submit an application for emergency-use authorization and require them to meet standards for accuracy. Tests will need to be found 90% “sensitive,” or able to detect coronavirus antibodies, and 95% “specific,” or able to avoid false positive results.
The tests, also called serology tests or simply blood tests, can potentially tell hospitals which health-care workers and which patients have already been exposed to the disease and recovered. Such use is under way, for example, at Partners HealthCare in the Boston area, to help Massachusetts General and other Harvard-affiliated hospitals know whether doctors and nurses have built up sufficient antibodies to the virus and can return to work.
Apart from fraud and inaccuracy, the tests also are of limited usefulness because researchers are still working to determine the precise level of antibodies sufficient to result in immunity. The hope has been that certain levels might create a kind of immunity passport, safely allowing health-care workers to return to the fray of treating severely ill coronavirus patients. Even top researchers, such as those at Mass General, said that research needs to be done before such a passport could truly work, but they are working to figure that out.
Antibody tests gauge the presence in the body of disease-fighting bodies that linger long after a patient has been sick or exposed. By contrast, polymerase chain reaction tests, generally done using swabs, test for whether a patient has the disease at the time of testing.
The FDA acted quickly in March because it had undergone criticism as early as February for not freely allowing leading academic laboratories and commercial developers to produce tests, after early assays from the federal Centers for Disease Control and Prevention had failed. As a result, the U.S. was flying blind earlier this year as to how many asymptomatic people might already be infectious and spreading the virus. Thousands of cases and deaths have followed.
Many of the antibody tests originated in China and elsewhere in Asia. Some antibody tests falsely claim they are FDA-approved, can diagnose current cases of Covid-19 or can be used at home.
FDA officials said they would take action against such violators, and will seize fraudulent tests at the U.S. border in the case of imports. In the case of any test with poor performance or misleading statements, the FDA now is requiring those failures be fixed or the tests pulled from the market.
Jeffrey Shuren, director of the FDA’s medical-device center, said criminal investigations are under way over tests believed to be fraudulent.
In a statement Monday, FDA Deputy Commissioner Anand Shah and Mr. Shuren said high-quality antibody tests are necessary to assess a population’s exposure to the virus, and to potentially identify recovered Covid-19 patients to collect blood plasma to be used in treating other patients. The officials pointedly noted that antibody tests aren’t used to diagnose current infection.
Currently, 13 tests on the market have received FDA emergency-use authorizations, meaning that they meet the agency’s standards. The FDA has been working with scientists at the National Cancer Institute to validate tests and have found “multiple good kits,” said one senior government official. One such test with high validation scores is from Mt. Sinai Hospital in New York, according to the government official. The hospital didn’t comment.
On Sunday, Roche Diagnostics AG said it won FDA clearance for its antibody test, and that its test is 100% accurate at detecting coronavirus antibodies in the blood and 98.8% accurate in ruling out those antibodies.
The FDA acknowledged it has been flexible but stated, “Flexibility never meant we would allow fraud. We unfortunately see unscrupulous actors marketing test kits and using the pandemic as an opportunity to take advantage of Americans’ anxiety.”
One of those improper activities involves promoting the antibody tests for diagnostic purposes. “These tests are intended to be non-diagnostic,” said one senior FDA official. “A serology test should not be a stand-alone decision point.” Rather, he said, the tests are designed to “understand sero-prevalence [how widely the virus has spread] in the population.”
Laboratory scientists say they have faced a wash of claims from test distributors and sales representatives that they say are questionable.
“People are just trying to get a piece of this pandemic money pie, and they’re willing to do anything,” said Joseph Wiencek, a lab director at the University of Virginia’s health system.
David Grenache, the chief scientific officer at TriCore Reference Laboratories, said he recently received a marketing email making unfounded claims from an independent sales representative pitching a test sold in the U.S. by Premier Biotech, a drugs-of-abuse testing company in Minnesota. Premier has been offering a Chinese-made test produced by Hangzhou Biotest Biotech Co.
The third-party sales representative who contacted one of Dr. Grenache’s colleagues pitched Premier’s test as one that “can be used anywhere and can “detect silent infection,” according to an email viewed by the Journal.
Both of those claims potentially run afoul of the FDA’s March edicts for marketing the tests, which include that they only be used by sophisticated laboratories and not be represented as capable of leading to a Covid-19 diagnosis. Dr. Grenache spoke to the saleswoman’s supervisor, who promised to relay his concerns about the two potential violations to Premier. He then forwarded the email to the FDA on April 25, urging the agency to stop allowing test-makers to sell serology tests without gaining at least an emergency authorization from the agency.
A prerecorded answering machine message at Premier said Monday that its antibody tests were out of stock “due to high demand.” A spokesman for Premier provided a form indicating the test’s limitations, including that it should not be used to make a diagnosis, and said the company requires all customers to sign it. The spokesman said the company has now applied for an FDA emergency-use authorization.
“We are committed to ensuring that all of our products are used for their intended purpose,” the company said in a statement, adding that it is concerned its name was used to market its products without its approval.