10 January 2022

Avacta Group plc

("Avacta" or "the Group" or "the Company")

Update on AffiDX^® SARS-CoV-2 antigen lateral flow test and detection of the Omicron variant

Avacta Group plc (AIM: AVCT), a clinical stage biopharmaceutical company developing innovative cancer therapies and powerful diagnostics based on its proprietary Affimer^® and pre|CISION™ platforms, provides an update on the performance of the AffiDX^® SARS-CoV-2 antigen lateral flow test (LFT) with the Omicron variant.

The performance of all rapid antigen tests has come under recent scrutiny in light of the large number of mutations in the Omicron variant of the SARS-CoV-2 virus and the US Food and Drug Administration, as well as other sources, has indicated that antigen tests generally will detect the Omicron variant but may have reduced sensitivity.[1]

As reported on 15 December 2021, the AffiDX^® SARS-CoV-2 antigen test has been shown to detect the Omicron variant of the SARS-CoV-2 virus in patient samples in a small clinical study. 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 AffiDX^® SARS CoV-2 antigen lateral flow test contains both a proprietary Affimer^® reagent and a commercially available antibody. Our data show that the Affimer^® reagent in the AffiDX^® test detects the Omicron variant with the same sensitivity as the Delta variant, and it is the performance of the antibody, with which the Affimer^® is paired in the test, that has been affected by the additional Omicron mutations. The Company has therefore independently taken the decision to pause sales of the AffiDX^® antigen test whilst it replaces the antibody in the product to ensure that its performance with the Omicron variant matches the high performance with previous mutations.

Alastair Smith, Chief Executive of Avacta Group, commented:

"The continued high performance of the Affimer^® reagent in the AffiDX^® antigen test, despite the large number of mutations in the Omicron variant, is testament to the robustness of our platform technology.

"As a responsible business, we set very high standards for ourselves and our products and have continually kept the performance of the AffiDX^® antigen test under review as new SARS-CoV-2 variants have arisen. 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. We have, of course, been unable to market the product in the UK since October 2021, as the product continues to await approval under the new CTDA regulatory process.

"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.

"The performance of other marketed SARS-CoV-2 antigen lateral flow tests may well be adversely affected by the Omicron variant. This mutant is already the dominant SARS-CoV-2 variant in many countries and may soon be the dominant variant globally. We therefore believe it is essential that similar Omicron sensitivity studies be performed on all SARS-CoV-2 antigen tests and the results communicated to ensure the public can have confidence in the results these tests generate."

ENDS

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About Avacta Group plc - https://www.avacta.com

Avacta Group is developing novel cancer immunotherapies and powerful diagnostics based on its two proprietary platforms - Affimer^® biologics and pre|CISION™ tumour targeted chemotherapies.

The Affimer^® platform is an alternative to antibodies derived from a small human protein. Despite their shortcomings, antibodies currently dominate markets, such as diagnostics and therapeutics, worth in excess of $100bn. Affimer^® technology has been designed to address many of these negative performance issues, principally: the time taken to generate new antibodies and the reliance on an animal's immune response; poor specificity in many cases; their large size, complexity and high cost of manufacture.

Avacta's pre|CISION™ targeted chemotherapy platform releases active chemotherapy in the tumour, which limits the systemic exposure that causes damage to healthy tissues, and thereby improves the overall safety and therapeutic potential of these powerful anti-cancer treatments.

The Group comprises two divisions: The therapeutics development activities are based in London and Cambridge, UK and the Group is generating near-term revenues from Affimer^® reagents for diagnostics, bioprocessing and research, through a separate diagnostics business unit based in Wetherby, UK.

Avacta's Diagnostics Division is developing an in-house pipeline of Affimer-based diagnostic assays, including the AffiDX^® SARS-CoV-2 Lateral Flow Rapid Antigen Test, and works with partners world-wide to develop bespoke Affimer^® reagents for third party products.

Avacta's Therapeutics Division is working to deliver a more tolerable and durable treatment response for oncology patients who do not respond to existing immunotherapies. By combining its two proprietary platforms the Group is building a wholly owned pipeline of clinically differentiated cancer therapies, aiming to extend the therapeutic benefits to all cancer patients. In 2021 Avacta transitioned to become a clinical stage biopharmaceutical company, commencing a phase I first-in-human, open label, dose-escalation and expansion study of AVA6000, a pro-doxorubicin, the Group's lead pre|CISION™ prodrug, in patients with locally advanced or metastatic selected solid tumours.

Avacta has established drug development partnerships with pharma and biotech, including a research collaboration with ModernaTX, Inc. (formerly Moderna Therapeutics Inc.), a multi-target deal with LG Chem worth up to $400m, a joint venture in South Korea with Daewoong Pharmaceutical focused on cell and gene therapies incorporating Affimer immune-modulators and a collaboration with Point Biopharma to develop radiopharmaceuticals based on the pre|CISION™ platform. Avacta continues to actively seek to license its proprietary platforms in a range of therapeutic areas.

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