Members of Congress have called on the FDA to re-evaluate its stance toward COVID-19 antibody tests. Since mid-March, the agency has allowed diagnostic developers to bring their products to market without any outside evaluation that the results they produce are accurate.
Instead, these manufacturers can proceed after validating the tests themselves, but they are not required to share those results. Companies must also print labels saying their antibody tests are not FDA approved or authorized and should not be used as the sole method to diagnose a coronavirus infection.
Several dozen diagnostic companies, many from China, have already taken the FDA up on this offer—notifying the agency of at least 140 different antibody tests that they intend to sell in the U.S. without seeking federal review. It is not known how many of these tests have been shipped or are available for purchase.
The quality of these tests has formed a new obstacle to the worldwide response to the COVID-19 pandemic, as many countries have put widespread antibody testing at the center of strategies.
Spain was forced to discard and return large numbers of antibody tests it imported from a Chinese company, after finding they were far less accurate than advertised. Later, Roche CEO Severin Schwan described global COVID-19 serological testing as “a disaster,” and compared many in the market to “amateurs.”
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Though it is not yet understood exactly how antibody readings, even accurate ones, can translate into broader immunity to the virus, many expect that they will play a key role in lifting lockdowns and getting people back to work. But false-positive results could send unprotected people back into harm’s way.
“I was shocked to learn that we do not have the ability to know whether the available serology tests work and the FDA has no plans to make that a reality,” said Rep. Raja Krishnamoorthi (D-Ill.), whose House subcommittee published a memo of its preliminary investigation (PDF) into the current state of the market.
The subcommittee cites FDA and CDC officials saying that any plans to base so-called immunity certificates or passports on test results are not yet feasible and that the agencies lack scientific evidence on whether there is an amount of antibody that confers immunity or how long the protective immune response could last.
Regarding test quality and performance, the FDA told congressional staff that it has asked laboratories and developers to voluntarily share their internal validation results, but the agency had not received any responses as of April 17, one month after relaxing its oversight policies.
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Compared to molecular tests—which sequence and match the RNA of the novel coronavirus to produce a result—the FDA has described antibody tests that gauge the body’s immune system response as a less-complicated endeavor that could proceed without review, dubbed “regulatory flexibility” by Commissioner Stephen Hahn.
This policy shift has led to confusion, with some antibody test developers falsely claiming their tests are FDA-approved or could diagnose COVID-19 at home. Still others have sold outrightly fraudulent tests online.
The agency has moved over 40 molecular diagnostics through its official review program for an Emergency Use Authorization, which allows the tests to proceed under a lower threshold of evidence compared to evaluations performed outside of a public health emergency.
To date, the FDA has granted seven of these authorizations to antibody tests—produced by Cellex, Ortho Clinical Diagnostics, Chembio Diagnostic Systems, the Mount Sinai Health System, Abbott, Autobio and DiaSorin.
The FDA is also working in an interagency collaboration to validate authorized and unauthorized antibody tests, alongside the CDC and the NIH—however, according to the subcommittee report, companies’ participation is voluntary.
Two weeks into the effort, the group had received seven submitted tests, out of the more than 100 already on the market, and had not yet validated any of them, the memo said. Preliminary results are expected by the end of the month.
In a news conference over the weekend, Sen. Chuck Schumer (D-N.Y.) said Congress aims to “sound the alarm, and urge a crackdown on something that is starting to infect the testing regime for COVID-19.”
The Senate minority leader said “there is no excuse for having all of the tests approved and authorized by the FDA,” and that he is formally calling on the agency to ramp up policing of online tests and issue cease and desist orders to companies offering tests without approval.