Antibody tests show up in Austin, but not all are FDA approved

Austin-based medical technology company Babson Diagnostics announced last week it will launch a local COVID-19 antibody testing service, but founder and CEO Eric Olson cautioned that it is still under development.

"There's this significant urgency, but there's also some confusion around what's available, and what the quality of the available tests actually is," he said.

Babson's announcement follows the news that many local healthcare providers—including Total Men's Primary Care, at-home urgent care Remedy and full-spectrum practice Victory Medical—are already offering antibody tests, promising results in as few as 15 minutes. But the available antibody tests for COVID-19 are imperfect.

Experts caution that only one antibody test—manufactured by the North Carolina company Cellex—has been approved for this use by the Food and Drug Administration and some may give false hope to patients looking for answers or proof of immunity.

Antibody testing, sometimes called a serum test or serology, works like a pregnancy test, indicating whether certain antibodies associated with a disease are present in a blood sample. It typically takes 10 to 12 days after a person has been exposed to the coronavirus to develop antibodies that will register on a test. As a result, the intended audience is patients who are no longer symptomatic—or never were.

"People are very interested in knowing if they've had the virus and now have the antibodies," a spokesperson for Total Men's wrote in an email.

Dr. Brian Metzger, a member of the Austin Public Health COVID-19 expert advisory panel and an infectious disease consultant to the Texas County Medical Society, wrote in an April 15 letter to TCMS members: "Anyone who is marketing [to] you with a serology test that is claiming to be FDA approved (other than the one test that has been granted [emergency use authorization]), they are doing so illegally."

Total Men's, Victory Medical and Remedy are using tests manufactured by Chinese companies—though none of them are claiming FDA approval.

Austin Public Health wrote in a statement emailed to Austonia that it is not using antibody tests at this time. "Those interested in obtaining an antibody test that is not FDA approved are taking a risk with the accuracy of that test," the statement reads.

Austin-Travis County Interim Health Authority Dr. Mark Escott told Travis County commissioners Tuesday that there are around 70 different antibody tests available, with varying levels of efficacy. "Some of them have substantial cross-reactivity, so it may show positive [results] because you had a non-COVID-19 coronavirus," he said. Other coronaviruses include those that cause the common cold, according to the MIT Technology Review.

Babson said antibody testing has many potential applications in relation to COVID-19, including helping to identify individuals who have developed antibodies—and possibly immunity—and so are best suited for work on the front lines.

"The use of serology is well established," Babson said, explaining that such tests help diagnose HIV, hepatitis and other diseases. "How to make a test that detects the [COVID-19] antibodies is new."