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Thinking of taking an antibody test? Consider this first.


Since early in the coronavirus outbreak, testing for COVID-19 has been critical to the public health response, and something many people want access to.  

There are two basic types of tests. Diagnostic tests are meant to determine if a person is currently infected, while antibody tests are meant to determine if a person was previously infected.

Antibody tests could, possibly, also tell you if you’ll be protected from re-infection. However, not only is the science around immunity to COVID-19 uncertain, but these antibody tests are known to result in false negatives and positives and the U.S. Food and Drug Administration has not approved any of these tests.

That doesn’t mean none of the tests is effective  it’s just they have not been through the FDA’s extensive review process. So under an emergency exception, the FDA has allowed some tests to go out to the market, explains Patti Zettler, an assistant law professor at The Ohio State University and a former FDA attorney.

But as tests go out, as one might expect, some bad players may be making false claims as a way to prey on people’s urge to get tested.

So how do we navigate all this uncertainty? Zettler explains.

What is the FDA doing right now with regard to these antibody tests?

Because of the current public health emergency that we’re in, what FDA has been doing to permit the sale and use of antibody (and diagnostic) tests is issuing what are known as emergency use authorizations. Emergency use authorizations are not traditional, standard FDA approval. Instead they are a way FDA can authorize products in public health emergency situations with less evidence supporting their effectiveness than we would normally expect.

That’s important for people to understand: Even the things that are FDA-authorized for COVID-19 right now have not gone through the standard processes health care professionals and patients and consumers generally expect.

Why is the FDA allowed to do emergency use authorizations?

Congress created the emergency use authorization pathway in 2004 to be used during a public health emergency. In other words, federal law allows FDA to issue emergency use authorizations in certain circumstances.

There’s always tension between developing evidence and speeding access for patients. It takes time to develop evidence to demonstrate that tests, treatments, vaccines and other medical products work.

Inherent to taking time to develop that evidence is some delay in patient access. Of course, we only know in hindsight, once we know a product actually works and is safe for a particular use, that we’re talking about access to a safe and effective product.

So, one way to think about the emergency use authorization process is that Congress has said that, in a public health emergency, FDA has the flexibility to balance this tension between evidence and access by shifting more toward making sure we get earlier access, even when we’re not sure products work.

Why should we even care about FDA approval?

There are at least two general reasons why FDA approval is important: One, it helps protect us, physically, from unsafe and ineffective products. Two, it requires that companies seeking to market their products do the research and produce the data that helps us understand what the products actually do.

One way to think about it is, to paraphrase a former FDA commissioner, Dr. Margaret Hamburg, "It’s not innovation if it doesn’t work." We don’t want products for products’ sake. We want products that work, and are safe.

That seems obvious, but then why do people jump on products that don’t have FDA approval?

With this public health emergency, but also with lots of health problems out there, there’s a tremendous and understandable desire to have testing or treatments immediately.

Because of the huge demand for COVID-19 antibody testing, for example, there will be companies seeking to take advantage of that market, and some may be selling products that are not authorized or are unsupported by evidence. Regulators, as a practical matter, cannot achieve 100% compliance. Consumers should be aware of this.  

Even the things that are FDA-authorized for COVID-19 right now have not gone through the standard processes health care professionals and patients and consumers generally expect.
Patti Zettler, Moritz College of Law
So who can people trust?

In terms of the questions about COVID-19 products, FDA has a lot of information on its website, including FAQs about COVID-19, information about companies that FDA has already warned for marketing “fraudulent” COVID-19 products and a list  of all of the emergency use authorizations the agency has issued. That’s one place to start, to get a better understanding of what FDA is doing, and which kinds of tests have gone through the emergency use authorization process.

Does this happen often in other areas of health care?

Yes. For example, during flu season you’ll often see products marketed to treat or prevent the flu that aren’t FDA approved. As another example, during the Ebola outbreak in West Africa several years ago, FDA warned about companies selling fraudulent products to treat or prevent that disease.

Anytime there’s a disease or condition that people are scared about and for which we lack good treatments or vaccines, there’s a market there to be exploited. Consumers should always be on the lookout for those sorts of products.