British Company Pulls COVID-19 Testing Product Off Market Following Drop in Effectiveness

A student holds a swab that is part of a lateral flow test at Swansea University in Swansea, Wales, on Dec. 8, 2020. (Matthew Horwood/Getty Images)

Britain’s Avacta Group has temporarily halted sales of its COVID-19 lateral flow test, according to a statement released Monday, in order to replace the antibody in the device and ensure that the effectiveness of detecting the Omicron variant is on par with that of previous strains.

Avacta, based in Cambridge, has since lost a third of its value following the news.

“Our determination to only provide high quality, high performance diagnostic tests has led us to the correct decision to pause all marketing of the AffiDX® lateral flow antigen test,” the company said in a press release. Avacta’s AffiDX antigen test has been able to detect Omicron in patient samples but mostly in cases where there is a high viral load.

“Whilst the AffiDX® antigen test is effective at identifying high viral loads of Omicron, further laboratory analysis carried out by Avacta indicates that the sensitivity of the test is reduced at lower viral loads when compared with the sensitivity of the AffiDX® test with previous SARS-CoV-2 variants.”

The antibody, which has been paired with a proprietary reagent in the test, detects Omicron with the same sensitivity as the Delta variant but has been affected by the additional Omicron mutations. Now, according to the report, the company is taking steps to replace the antibody to enhance its performance in detecting the latest variant.

Omicron is now the dominant variant in the United States, with more than 95 percent of the infections now attributed to it, according to the latest CDC data.

However, Omicron-infected patients have been found to exhibit lower hospitalization rates, while a British doctor has claimed that the milder variant could be the start of COVID-19 evolving into an endemic, something like a common cold.

The theory is that a highly-transmissible version of the virus would infect people rapidly but leave behind a more resistant population, given that natural immunity offers better protection than vaccines.

Avacta had entered into an exclusive agreement with Medusa Healthcare to market the new test, Meduflow, in international markets. Meduflow had recently received a CE mark of approval from the UK government to be used as a consumer self-test within the country and the wider European Union. The test consists of a nasal swab that gives results in about 20 minutes.

Along with other COVID-19 testing companies, Avacta had to pull some of its products from the local market after a new review system was deployed, which has not yet given approvals for previously recognized products. COVID-19 testing remains a highly profitable business.

“We believe COVID-19 testing remains a long-term commercial opportunity. We will therefore use the robustness of the Affimer® platform, and what we have learned about the SARS-CoV-2 virus, to generate the next generation antigen test that will be as resilient as possible to any future mutations,” said Alastair Smith, chief executive of Avacta Group.