Avacta reports 'encouraging' early signals from AVA6000 clinical data

(Sharecast News) - Avacta said on Monday that updated clinical data for its AVA6000 cancer therapy showed encouraging early efficacy signals in patients with salivary gland cancers, alongside a continuing favourable safety profile.

The AIM-traded clinical-stage biopharmaceutical company said updated Phase 1a/1b pharmacokinetic, safety, toxicity and preliminary efficacy data for faridoxorubicin, also known as AVA6000, were presented at the 2026 American Society of Clinical Oncology annual meeting in Chicago.

AVA6000 is Avacta's preCISION-enabled form of doxorubicin, designed to release the active chemotherapy payload in the tumour microenvironment through activation by the FAP enzyme.

Avacta said the therapy demonstrated a safety profile consistent with earlier Phase 1a dose-escalation data at the recommended expansion dose of 310 mg per square metre.

It said rates of toxicities remained lower than those historically observed with conventional doxorubicin, despite the dose being nearly three times the maximum tolerated dose level for conventional doxorubicin.

In the salivary gland cancer expansion cohort, Avacta said there were four confirmed partial responses and nine minor responses among 38 evaluable patients.

The disease control rate remained at 92%, with 35 of 38 patients recording stable disease or a response.

Nine patients were continuing treatment and a further 11 remained in follow-up for disease progression.

The company also said pharmacokinetic and exposure-response data had supported the removal of the lifetime maximum exposure limit for AVA6000.

It said no severe cardiac toxicity events had been reported among the 111 patients dosed to date, with only minimal changes in left ventricular function observed.

Avacta said only four patients, representing less than 4% of those dosed, had reported significant reductions in left ventricular ejection fraction, while no cardiomyopathy events of any grade had been observed.

An exposure-response analysis found no meaningful relationship between changes in left ventricular ejection fraction and exposure to released doxorubicin, suggesting that the cardiac toxicity associated with conventional doxorubicin was not being observed with released doxorubicin from faridoxorubicin.

Avacta said it had received health authority agreement with that conclusion, allowing the lifetime maximum dosing limit to be removed from the study protocol earlier this year.

Chief executive Christina Coughlin said the data further underscored Avacta's confidence in AVA6000 and its preCISION platform.

"We are particularly encouraged by signs of efficacy in patients with salivary gland cancers and the consistency of these data from Phase 1a and 1b support the potential for this agent to move to later stage trials," she said.

"The excellent safety profile was further demonstrated by the absence of severe cardiac toxicity and lifting of the lifetime maximum, following careful analysis of drug concentration versus effect on the heart."

Avacta said the study was continuing to enrol patients, with further data from the AVA6000 programme due to be presented at the BIO International Convention in San Diego later in June.

At 1342 BST, shares in Avacta Group were down 3.04% at 76.6p.

Reporting by Josh White for Sharecast.com.

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