Avacta's Faridoxorubicin Shows Promising Tumor Shrinkage in Salivary Gland Cancer Phase 1b Trial
Key Insights
Avacta's faridoxorubicin (search) demonstrated clinically meaningful tumor shrinkage in 30% of salivary gland cancer (search) patients, with two confirmed partial responses and seven minor responses in a Phase 1b trial.
The peptide drug conjugate achieved a 90% disease control rate across both Phase 1a and Phase 1b cohorts, targeting a cancer type that typically doesn't respond to chemotherapy.
Faridoxorubicin (search) utilizes Avacta's preCISION platform to selectively deliver doxorubicin to tumor cells via fibroblast activation protein-alpha (search) cleavage in the tumor microenvironment.
Avacta Group PLC announced compelling new clinical data showing that its investigational peptide drug conjugate faridoxorubicin (search) (AVA6000) produced "robust and meaningful" tumor shrinkage in patients with salivary gland cancer (search) (SGC) enrolled in an ongoing Phase 1b trial. The data demonstrated confirmed partial and minor responses consistent with previously reported Phase 1a results.
Clinical Efficacy Results
Of the 30 patients with salivary gland cancer (search) treated at doses of 250 mg/m² and above across both Phase 1a and Phase 1b cohorts, nine experienced clinically meaningful disease shrinkage. This included two confirmed partial responses (greater than 30% tumor shrinkage) and seven minor responses (10-30% tumor shrinkage) using RECISTv1.1 criteria.
The combined disease control rate reached 90% across both Phase 1a and Phase 1b patients, with 27 of 30 patients demonstrating partial responses, minor responses, or stable disease. In the Phase 1b cohort specifically, median progression-free survival has not been reached, with a median follow-up exceeding 15 weeks at the data cutoff. Thirteen of 19 patients in the Phase 1b cohort remain on therapy, with an additional two patients continuing in progression-free survival follow-up.
Targeting an Unmet Medical Need
Salivary gland cancer (search) represents a significant unmet medical need, accounting for 6-8% of head and neck cancers with approximately 2,500 cases diagnosed annually in the United States. The disease notably does not respond to chemotherapy, has no standard therapy defined in the metastatic setting, and carries a five-year survival rate of approximately 42% in advanced stage disease, according to American Cancer Society data cited by Avacta.
"SGC cancer is a devastating disease with no established standard of care treatment options," said Christina Coughlin, MD, PhD, CEO of Avacta. "The clinically meaningful tumor shrinkage and prolonged progression free survival we have observed in the study highlight faridoxorubicin (search)'s potential as an important new treatment option for patients with SGC and other solid tumors."
Mechanism of Action
Faridoxorubicin (search) represents the first peptide drug conjugate in Avacta's pipeline, utilizing the company's proprietary preCISION platform. The drug consists of doxorubicin conjugated with Avacta's proprietary preCISION peptide and is specifically cleaved by fibroblast activation protein-alpha (search) (FAP (search)), which is over-expressed in the tumor microenvironment. This mechanism enables targeted release of the doxorubicin payload directly to cancer cells.
Translational data from the patient population continue to demonstrate the effectiveness of the preCISION platform, with optimal payload release observed even at the lowest levels of FAP (search) expression, according to the company. This finding supports potential broad market opportunities for preCISION medicines across Avacta's pipeline.
Safety Profile and Next Steps
Safety findings from 22 patients in the Phase 1b arm aligned with data previously reported from the Phase 1a cohort. Faridoxorubicin (search) continues to demonstrate a favorable safety profile alongside its efficacy in salivary gland cancer (search) patients.
Based on the preliminary favorable efficacy and safety data observed in the Phase 1b cohort, enrollment will continue with further data updates across both Phase 1a and Phase 1b cohorts expected in the first half of 2026. The Phase 1b data will mature as the company continues to collect survival data in this cohort.
"These data continue to reinforce our belief in the transformative potential of our preCISION peptide drug conjugates to expand the therapeutic index and increase the efficacy of highly potent therapeutics and further strengthens our confidence across our broader pipeline," Coughlin stated.