1 September 2022

Avacta Group plc

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

Phase I clinical study of AVA6000 to advance to the fourth cohort

Avacta Group plc (AIM: AVCT), a clinical stage oncology drug company and developer of powerful diagnostics based on its innovative Affimer^® and pre|CISION™ platforms, announces that the first-in-human Phase I trial (ALS-6000-101) of AVA6000 Pro-doxorubicin will advance to the fourth dose cohort of patients following a positive review of the safety and tolerability data from the dosing of the third cohort.

Avacta's Safety Data Monitoring Committee (SDMC), comprised of clinicians currently recruiting patients, has completed its review of the safety data from the third cohort dosed with AVA6000 at 160mg/m² in the ongoing Phase I trial. Following this review, the SDMC has recommended that the clinical trial continues as planned and escalates to the next dose of AVA6000 at 200mg/m².

AVA6000 is a novel form of doxorubicin that has been modified with Avacta's pre|CISION™ FAP-activated delivery platform to improve its safety and therapeutic index. AVA6000 has been designed to limit cell penetration of the drug, and therefore its cell killing effect, until it is specifically activated by fibroblast activation protein α (FAP) which is in high concentration in many solid tumours compared with healthy tissues. The resulting reduced exposure of healthy tissues to active doxorubicin has the potential to significantly increase its therapeutic index by reducing the incidence of adverse effects, including cardiotoxicity and myelosuppression. Anthracyclines such as doxorubicin, a generic chemotherapeutic agent, with a market size that is expected to grow to $1.38bn by 2024[1], are widely used as part of standard of care in several tumour types, but its use is limited by cumulative dose toxicity associated with cardiomyopathy.

Dr Alastair Smith, Chief Executive Officer of Avacta Group, commented:

"We are very much encouraged by this recommendation from the SDMC to move onto the fourth dose cohort in our ongoing ALS-6000-101 Phase 1 dose escalation study. This very positive progress reflects the safety profile and tolerability demonstrated in patients enrolled in the study to date."

-Ends-

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 as it forms part of UK domestic law by virtue of the European Union (Withdrawal) Act 2018 ('MAR'). Upon the publication of this announcement via Regulatory Information Service ('RIS'), this inside information is now considered to be in the public domain.

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

Avacta's pre|CISION™ targeted chemotherapy platform is designed to selectively release active chemotherapy in FAP rich tumour tissue to limit the systemic exposure that causes damage to healthy tissues, and thereby aims to improve the overall safety and therapeutic potential of these powerful anti-cancer treatments.

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

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 generate more tolerable and durable treatments for oncology patients who do not respond to existing therapies. By combining its two proprietary platforms the Group is building a wholly owned pipeline of clinically differentiated cancer therapies. In 2021 Avacta transitioned to become a clinical stage biopharmaceutical company, when it commenced a phase I trial in patients with locally advanced or metastatic selected solid tumours. The study was a first-in-human, open label, dose-escalation and expansion study of the Group's lead pre|CISION™ prodrug, AVA6000 (a pro-doxorubicin).

Avacta has established drug development partnerships with pharma and biotech, including 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 recent license agreement with Point Biopharma for them to develop radiopharmaceuticals based on the pre|CISION™ platform.

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