Biopharmaceutical company Avacta Therapeutics (AIM: AVCT) on Wednesday reported positive preliminary Phase 1b data for faridoxorubicin (AVA6000) in patients with salivary gland cancer, showing clinically meaningful tumour shrinkage and results consistent with Phase 1a data presented at the European Society of Medical Oncology in September 2025.

Data from the ongoing Phase 1b study showed confirmed partial and minor responses, contributing to a combined disease control rate of 90% across Phase 1a and Phase 1b cohorts. Across 30 evaluable patients treated at doses of 250 mg/m² and above, two confirmed partial responses and seven minor responses were observed, with 27 patients achieving partial response, minor response or stable disease.

Phase 1b results included 19 patients evaluable for efficacy, with median progression-free survival not yet reached and median follow-up exceeding 15 weeks. Thirteen patients remain on treatment, with a further two in progression-free survival follow-up. Safety data were consistent with earlier Phase 1a findings.

Faridoxorubicin is Avacta's first peptide drug conjugate and uses the pre|CISION platform to selectively release doxorubicin in the tumour microenvironment via fibroblast activation protein-alpha, aiming to improve efficacy while reducing systemic toxicity.

Based on favourable early efficacy and safety data, Avacta said enrolment in the Phase 1b cohort will continue, with further updates from both Phase 1a and Phase 1b expected in the first half of 2026.