Avacta Group plc announced the successful completion of the sixth dose escalation cohort in the ALS-6000-101 dose escalation Phase 1 clinical trial to evaluate the safety and tolerability of AVA6000 and provides an update on clinical progress. The data from the sixth cohort continue to show an excellent safety profile for AVA6000. Additionally, a tumour response (significant tumour volume reduction) has been confirmed in a patient with soft tissue sarcoma on the trial, and there are further indications of clinical activity in patients across other indications.

A tumour targeted form of doxorubicin that has been chemically modified with Avacta's pre|CISION?? platform, designed to reduce systemic side effects by targeting the release of the active chemotherapy to tumour tissue. A total of 35 patients with a range of advanced and/or metastatic solid tumours have now been dosed at the clinical trial in sites in the UK and United States.

A clinically significant reduction in the toxicities usually associated with standard doxorubicin chemotherapy continues to be observed. The excellent safety profile of AVA6000 should allow more frequent and/or higher dosing compared with the standard doxorubic in regimen which could in turn improve the outcome for patients. Therefore, in parallel with the completion of cohort 7, the Company intends to begin a short study to explore more frequent dosing (fortnightly) of AVA6000 as a first line treatment in patients with soft tissue sarcoma.

The study is expected to begin in Fourth Quarter 2023 subject to receipt of approval of a protocol amendment from the US Food & Drug Administration (FDA). The study is designed to determine whether fortnightly or three weekly dosing should be the recommended Phase 2 dosing regimen, as well as potentially providing additional indications of activity in soft tissue sarcoma patients. The study will replace the much longer planned Phase 1b efficacy study, and is expected to allow the Company to bring forward the start of the potentially pivotal Phase 2 efficacy study into 2024.

The pre|CISIONTM platform is doing exactly what it was designed to do - target the release of active chemotherapy to the tumour tissue, sparing healthy tissues and improving the safety and tolerability of the drug whilst delivering potentially superior efficacy. Avacta's lead programme, AVA6000, is a pre|CISION?? tumour-targeted form of the established chemotherapy doxorubicin.

A AVA6000 is in Phase I clinical trials in patients with locally advanced or metastatic selected solid tumours. The Affimer®? platform is an alternative to antibodies that has been designed to address many of the drawbacks of antibodies which, despite their shortcomings, currently dominate the immuno-diagnostics and immuno-therapeutics markets.

The pre|CISION???? platform is a pre|CISIONTM tumour-targeted forms of the established chemotherapy doxORubicin. AVA6000 is in PhaseI clinical trials in patients with locally Advanced or metastatic selected solid tumour.

The Affimer®? platforms is an alternative to antibody that has been designed to address Many of the advantages of antibodies which, despite their limitations, currently dominate the immuno - immuno-diagnostics and Immuno-therapeutics markets". The pre|CISIONTM??

platform is designed to achieve earlier commencement of pivotal Phase 2 study in 2024.