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Avacta Announces U.S. FDA Agreement on Pivotal Trial Design for AVA6000 in Patients with Salivary Gland Cancer

Single pivotal trial, with progression-free survival as primary endpoint needed for full approval

LONDON and PHILADELPHIA - June 25, 2026 - Avacta Therapeutics (AIM: AVCT, "the Company", "Avacta"), a clinical stage biopharmaceutical company developing pre|CISION^®, a tumor-activated oncology delivery platform, today announces that it has agreed the pivotal trial design for faridoxorubicin (AVA6000, pre|CISION-enabled doxorubicin) with the U.S. Food and Drug Administration (FDA) for a potential full regulatory approval.

This would comprise a single pivotal study with faridoxorubicin in patients with salivary gland cancer (SGC), with progression-free survival (PFS) as the sole primary endpoint for full approval. Furthermore, the proposed study population includes both first- and second-line patients, in the most prevalent subsets of SGC, while more rare subsets (e.g. undifferentiated histology and mucinous tumor types) are excluded due to differing natural histories.

Christina Coughlin, CEO of Avacta, commented:

"Our recent constructive discussions with the FDA have resulted in a clear path forward for our Gen One product faridoxorubicin towards full approval, based on one pivotal trial with a single primary endpoint of PFS.

"This would allow the company to move directly to the pivotal trial when the Phase 1b data are mature, enabling time savings with the clear focus on PFS data to secure approval. It provides further clarity in our continuing conversations with potential partners, with a defined route through clinical development towards potential approval and commercialization.

"The FDA had previously agreed to lifting the lifetime maximum dosing with faridoxorubicin at US sites, based on its excellent safety profile and absence of severe cardiac toxicity. The Company remains committed to progressing faridoxorubicin into further clinical development only with the support of a partner."

-Ends-

For further information from Avacta, please contact:

About Avacta - https://avacta.com/

Avacta Therapeutics is a clinical-stage life sciences company expanding the reach of highly potent cancer therapies through its proprietary pre|CISION® platform. pre|CISION® is a payload delivery system based on a tumor-specific protease (Fibroblast Activation Protein or FAP) that is designed to concentrate highly potent payloads in the tumor microenvironment while sparing normal tissues. Avacta's innovative pre|CISION® peptide drug conjugates (PDC) are a novel entry to the XDC drug class, leveraging the success of antibody drug conjugates with alternative methods of delivery beyond antibodies. 

Our pre|CISION® PDCs leverage this tumor-specific release mechanism to provide unique benefits over traditional antibody drug conjugates, releasing active payload in the tumor and reducing systemic exposure and toxicity which enables dosing to be optimized to deliver the best outcomes for patients. The lead clinical program is faridoxorubicin (AVA6000), a Gen One FAP-enabled pre|CISION® version of doxorubicin that delivers the payload directly in the tumor with limited peripheral blood exposure and has demonstrated preliminary activity in tumor types sensitive to doxorubicin including salivary gland cancer and soft tissue sarcoma.

About FAP-Exd (AVA6103)

AVA6103 is the second clinical candidate and is the first asset in the pipeline based on the Gen Two innovative pre|CISION^® sustained release mechanism that provides for prolonged release of payload directly in the tumor, minimizing systemic exposure.  AVA6103 is being evaluated in the FOCUS-01 Phase 1 trial (FAP-Exd in Oncologic Cancers with Unmet needS). Preclinical data suggest this approach has optimized payload delivery with a high intratumoral concentration and prolonged exposure of released payload in the tumor, coupled with limited systemic exposure to the released payload.