Yorkshire drug firm's Covid-19 test can detect highly transmissible Kent strain

The Wetherby-based group said its lateral flow test detects both the B117 "Kent strain and the D614G variants of the virus, as well as the original strain.

The "Kent" strain was first detected last September and its rapid spread across the country was a major reason for the latest lockdown, which was announced in early January.

Avacta said that the SARS-CoV-2 virus, like most viruses, mutates over time into slightly different variants. Some of these variants are more infectious and therefore more rapidly transmissible, and have the potential to become dominant strains.

Early on in the pandemic, a variant referred to as D614G appeared, which rapidly became the dominant strain globally.

The B117 variant, which was first observed in Kent, is prevalent in the UK and has been found in more than 50 countries. According to Professor Sharon Peacock, professor of Public Health and Microbiology at Cambridge University, B117 is likely to become the next dominant strain globally.

Avacta has carried out analytical tests with the spike proteins isolated from both the B117 and D614G variants, and has confirmed that its AffiDX SARS-CoV-2 rapid antigen lateral flow test detects both of these variants as well as the original strain.

Dr Alastair Smith, chief executive of Avacta Group, said: “We are pleased to confirm that Avacta’s rapid antigen test detects the B117 strain, an important variant of the SARS-CoV-2 virus and one which is especially prevalent in the UK. We have also shown that our test detects the D614G variant, the current dominant global strain.

"We will continue to monitor the performance of the Affimer reagents with future dominant variants as they become available to us."

Affimers are Avacta’s high-tech alternative to antibodies.

Dr Smith said: "Since the Affimer reagents we use in Avacta’s range of SARS-CoV-2 tests do not bind in the region of the spike protein where the dominant mutations appear, we do not anticipate that the performance of the tests will be affected.

"Now that we have developed a robust lateral flow test architecture, we can easily insert Affimer reagents that that can be very rapidly developed for new variants ifnecessary, and indeed in response to any other future pandemic virus."

Avacta's next key milestone is full clinical validation and CE marking of its lateral flow antigen test which it anticipates will be around the end of this month.

"I look forward to updating the market when that milestone is achieved,” said Dr Smith.

Analyst Mark Brewer at FinnCap said: "Confirmation that Avacta’s AffiDX SARS Co-V-2 rapid antigen lateral flow test can detect the dominant mutated variants of the SARS CoV-2 virus is clearly a positive message for investors as it does not undermine the current test format, for which we await final clinical validation and CE marking around the end of the month.

"It is not unsurprising, given the Affimers in the tests do not bind in the region of the spike protein where the dominant mutations appear, but nevertheless, is reassuring.

"The ability to use the current test format to ‘plug and play’ new Affimer reagents for new variants, if necessary, as well as for any future pandemic virus, provides a lateral flow test format of long-term value. We reiterate our target price of 310p."