US warns against use of particular lateral flow test UK is buying in bulk

Federal health agency says it has ‘significant concerns’ about test’s performance

A worker processes an Innova lateral flow test taken by a Hull University student in April (AFP/Getty)

The US has told its citizens to stop using a lateral flow Covid-19 test (LFT) favoured by the British government due to concerns about its performance.

The Innova Sars-CoV-2 Antigen Rapid Qualitative Test is a main pillar of the UK’s test and trace system, with more than a billion tests supplied so far in contracts worth around £3bn.

As a result, Innova, a US diagnostics firm, recently announced that it is ramping up its UK operations by opening a factory in Wales, which will produce millions of its LFTs per day.

However, the US Food and Drug Administration (FDA) has called the test’s reliability into question, telling people to stop using it.

“The FDA has significant concerns that the performance of the test has not been adequately established, presenting a risk to health,” it said in a statement released on Thursday.

The federal agency added that some of the performance claims Innova makes about its products were not corroborated by clinical studies.

It is concerned by the risk of the tests giving false-positive and false-negative results, and has therefore decided not to authorise the LFT’s use.

The FDA has also written a warning letter to Innova, after the firm recalled its product on 23 April in what the agency described as a recall of the “most serious” kind.

Its decision raises significant pressure on the UK government over its mass use of Innova’s LFT and comes as the British Medicines and Healthcare products Regulatory Agency (MHRA) is considering whether to extend the product’s licence.

Back in December, the regulator issued a six-month long emergency use authorisation (EUA) for Innova’s test, which expires on 22 June.

“A decision [will be] taken on whether it remains in the interests of the protection of health for a further authorisation or an amendment to this authorisation to be made,” the MHRA told the Department of Health in a letter.

The MHRA allegedly was concerned by the department’s move in April to include Innova’s LFT as part of its mass testing programme, calling it “a stretch” of its EUA authorisation.

A spokesperson for the Department of Health insisted that every test used as part of the national programme “has undergone rigorous clinical evaluation”.

Responding to the FDA’s statement, Innova told The Independent that the efficacy of its rapid antigen test has been “widely” scrutinised with data from the UK’s mass testing programme.

“Innova understands the FDA’s health risk concern for the US market as they have not evaluated or authorised the Innova test in the US,” it added.