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RNS Number : 8578W Avacta Group PLC 30 September 2026 THIS ANNOUNCEMENT AND THE INFORMATION CONTAINED IN IT , IS RESTRICTED AND IS NOT FOR RELEASE , PUBLICATION OR DISTRIBUTION , IN WHOLE OR IN PART , DIRECTLY OR INDIRECTLY , IN , INTO OR FROM THE UNITED STATES , AUSTRALIA , CANADA , JAPAN , SOUTH AFRICA OR ANY OTHER JURISDICTION IN WHICH SUCH RELEASE , PUBLICATION OR DISTRIBUTION WOULD BE UNLAWFUL . PLEASE SEE THE IMPORTANT NOTICES IN THIS ANNOUNCEMENT . THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION FOR THE PURPOSES OF THE MARKET ABUSE REGULATION ( EU ) 596 / 2014 WHICH FORMS PART OF UK LAW BY VIRTUE OF THE EUROPEAN UNION ( WITHDRAWAL ) ACT 2018 ( AS AMENDED ) ( " MAR " ) . FOR IMMEDIATE RELEASE Avacta Group plc ( " Avacta " or the " Company " ) Interim Results for the Six Months to June 30 , 2026 , and Business Update LONDON and PHILADELPHIA - September 30 , 2026 - Avacta Therapeutics ( AIM : AVCT , " the Company " , " Avacta " ) , a life sciences company developing innovative , targeted oncology drugs , today publishes its unaudited interim results for the six months ended June 30 , 2026 ( " H1 26 " ) . H1 highlights and post period Research & development Next Generation pre | CISION® pipeline AVA6103 ( FAP - Exd ) Preliminary preclinical and clinical data with AVA6103 have been presented recently . Data reported in the Phase 1a trial in patients with select solid tumors demonstrate proof of mechanism with two key findings : § AVA6103 pre | CISION® controlled - release exatecan demonstrates a clean safety profile through the first three dose levels , including a payload dose level 50 % higher than the maximum tolerated dose ( MTD ) of conventional exatecan at dose level 3 , and § The comparison of the preclinical modeled pharmacokinetic ( PK ) data and clinical trial PK data demonstrates an exceptional alignment through the first 3 dose levels with controlled release of exatecan evident in patients for days after dosing o The first head - to - head preclinical comparison of AVA6103 and EnhertuⓇ , a marketed antibody drug conjugate ( ADC ) that targets HER2 , demonstrates that AVA6103 shows better antitumor activity vs. EnhertuⓇ , with deep and durable responses delivered by our dose dense regimen that has been applied in the FOCUS - 01 trial .