New studies to test performance of home COVID-19 tests for omicron

UMass Chan Medical School researchers and their partners in the National Institutes of Health Rapid Acceleration of Diagnostics initiative are starting new studies to determine if the performance of at-home COVID-19 antigen tests currently on the market in the U.S. is affected by the omicron variant, which has been raging across the globe since late fall.

Also, another slate of studies by the RADx Tech team will provide data to help the Food and Drug Administration quickly assess the quality of tests, including those on the market in other countries, to get more tests on U.S. shelves. The NIH initiative, called Independent Test Assessment Program, provides resources for independent clinical studies and helps manufacturers meet FDA authorization protocols through an accelerated pathway.

The demand for rapid at-home tests has grown exponentially as the SARS-CoV-2 virus mutates and new variants spread. To help meet this demand, two new products, one manufactured by SD Biosensor and distributed by Roche and the other manufactured by Siemens, received FDA emergency use authorization in December through the ITAP program.

Yet sufficient test supply is just one challenge. With the latest dominance of the highly transmissible omicron variant, health officials, researchers and consumers want to know how effective rapid home tests are in this evolving pandemic.

“There’s a lot of interest right now in whether the tests that are out in the market can detect omicron,” said Nathaniel Hafer, PhD, assistant professor of molecular medicine and lead investigator of the RADx Tech Clinical Studies Core Logistics Team. “Our team here at UMass Chan is one of several groups of different scientists who are looking at that in more depth and more completely to be able to say for sure. But so far, the early signs are positive.”

Dr. Hafer said a point of debate has been when, not so much whether, home antigen tests detect an infection, including recent variants.

Scientists have known that PCR tests are more likely to detect an infection early during the course of COVID-19, because the test amplifies genetic material so that even a small amount of coronavirus genetic material in the patient’s sample can be detected. Most antigen tests, which are often used at home, are faster and less costly than PCR tests but they don’t amplify genetic material. So, larger amounts of the virus would need to be present for a positive result, which is usually about a day or two after a PCR test would pick it up.

“The question is, is the delay from omicron prolonged? That we’re not 100 percent sure about yet. But we’re doing lots of studies right now to try to figure that out,” Hafer said.

Hafer and other researchers are starting studies in which participants will test themselves at home for 10 days, taking a PCR test and one of the FDA-authorized over-the-counter antigen tests daily. Researchers will assess how the test results compare with one another.

Locally, participants can enroll at the Mercantile Center test site in downtown Worcester, or people from across the U.S. can enroll digitally. For more information, go to COVID19testus.org.

“One of the exciting things that we’ve moved into in the last few months is digital studies where people can participate in these trials anywhere in the United States,” Hafer said. “It allows us to enroll much more rapidly than we could otherwise. It also allows people to participate without having to travel to a site.”

UMass Chan and its RADx Tech partners have enrolled more than 12,000 participants in COVID-19 rapid home test studies over the past 13 months, according to Hafer.

“I think that just shows the power of these kinds of studies and the ability to accumulate a lot of data really rapidly, which is of high value for the nation, NIH and our investigators,” he said.