New At-Home COVID Tests Come On-Line, Might Ease Shortages Somewhat
The Food and Drug Administration has quickly approved two additional at-home COVID-19 tests, and both manufacturers suggest their products should be available this month. At the same time, the FDA has raised questions about the accuracy of some of the assays and offers advice to pharmacy staff and others on how to deal with possible reduced sensitivity. Here are more details.
WASHINGTON, DC – Two new over-the-counter, at-home COVID-19 tests which recently received emergency use authorization from the Food and Drug Administration should help ease shortages, perhaps as early as this month.
The tests, one manufactured by SD Biosensor and distributed by Roche and the other manufactured by Siemens, received emergency use authorization (EUA) by the Food and Drug Administration (FDA) in late December. The applications were evaluated through the Biden Administration’s new accelerated pathway.
The National Institutes of Health (NIH) invested $70 million from the American Rescue Plan and coordinated with FDA to help bring more high-quality, at-home tests onto the market in the United States. NIH’s new Independent Test Assessment Program (ITAP) established an accelerated pathway to support FDA evaluation of tests with potential for large-scale manufacturing. The program is an extension of the NIH Rapid Acceleration of Diagnostics (RADx) initiative.
In a press release, Roche said its COVID-19 At-Home Test will be available across the United States and following local guidelines and testing strategies starting this month. At the time of launch, the company said it has the capacity to produce tens of millions of tests per month to help support the pandemic response.
Siemens also announced that its test, which is specific to the United States, is expected to be available starting in January. Siemens Healthineers said it has secured dedicated production capacity for U.S. products in the tens of millions per month.
The White House has committed to increasing access to COVID-19 testing, with President Joe Biden saying that the federal government would purchase half a billion at-home tests to be provided to Americans for free this winter, starting in January.
The FDA, meanwhile, said it still recommends testing to help control the fast-moving Omicron variant, but said on its website, “The SARS-CoV-2 virus has mutated over time, resulting in genetic variation in the population of circulating viral strains over the course of the COVID-19 pandemic. Molecular, antigen, and serology tests are affected by viral mutations differently due to the inherent design differences of each test.”
Essentially, the agency suggests that rapid antigen tests for COVID-19 might be less effective at detecting the Omicron variant, adding that, while it appears that COVID-19 antigen tests "do detect the omicron variant but may have reduced sensitivity.”
The FDA recommends that pharmacy staff and other healthcare providers, as well as clinical laboratory staff, take the following into consideration:
Genetic variants of SARS-CoV-2 arise regularly, and false-negative test results can occur.
- Consider negative results in combination with clinical observations, patient history, and epidemiological information.
- Repeat testing with a different EUA authorized or FDA cleared molecular diagnostic test (with different genetic targets) might be needed if COVID-19 is still suspected after receiving a negative test result.
- Test performance might be affected by certain variants.
- Tests with single targets are more susceptible to changes in performance due to viral mutations, i.e., they are more likely to fail to detect new variants.
- Tests with multiple targets are more likely to continue to perform as described in the test's labeling as new variants emerge. Multiple targets mean that a molecular test is designed to detect more than one section of the SARS-CoV-2 genome or, for antigen tests, more than one section of the proteins that make up SARS-CoV-2.
The agency adds that “preliminary studies evaluating the performance of some antigen tests using patient samples containing live virus, which represents the best way to evaluate true test performance in the short-term. Early data suggests that antigen tests do detect the Omicron variant but may have reduced sensitivity.”
FDA emphasizes that it “continues to authorize the use of these tests as directed in the authorized labeling and individuals should continue to use them in accordance with the instructions included with the tests. Antigen tests are generally less sensitive and less likely to pick up very early infections compared to molecular tests. In following the FDA's long-standing rapid test recommendations, if a person tests negative with an antigen test but is suspected of having COVID-19, such as experiencing symptoms or have a high likelihood of infection due to exposure, follow-up molecular testing is important for determining a COVID-19 infection.”