Avacta Therapeutics announced compelling new data in patients with salivary gland cancer (SGC) enrolled in the ongoing Phase 1b trial of faridoxorubicin (AVA6000). The data show confirmed partial and minor responses, consistent with data previously reported from the Phase 1a part of the study. Faridoxorubicin is the first peptide drug conjugate (PDC) in Avacta's pipeline.
It consists of doxorubicin conjugated with Avacta's proprietary pre|CISION®? peptide and is specifically cleaved (released) by fibroblast activation protein-alpha (FAP), which is over-expressed in the tumor microenvironment, enabling targeted release of the doxorubicin payload. SGC accounts for 6-8% of head and neck cancers, with approximately 2,500 cases diagnosed in the U.S. each year.1 SGC is a disease that does not respond to chemotherapy, has no standard therapy defined in the metastatic setting and a five-year survival rate of approximately 42%2 in advanced stage disease.
Avacta's recent data demonstrate continued robust and meaningful tumor shrinkage in patients with SGCs and a combined disease control rate of 90% across Phase 1a and Phase 1b patients. Based on the preliminary favorable efficacy and safety data observed in the Phase 1b cohort in this part of the trial, enrollment will continue in this cohort with further data updates across the Phase 1a and Phase 1ss cohorts expected in 1H 2026. These data demonstrate ongoing evidence of durable anti-tumor activity in patients with SGC (both treatment-naive and those who have failed earlier lines of therapy), that is supported by ongoing RECIST 3 responses (both partial and minor responses) and continued observation of a robust disease control rate and strong progression-free survival (PFS) data.
The trial enrolled both a Phase 1a cohort (n=11) and Phase 1b cohort to date (n=19 evaluable for efficacy) for a total of 30 patients with SGC. Of the 30 patients with SGC treated at the dose of 250 mg/m2 and above and evaluable for efficacy, nine experienced clinically meaningful disease shrinkage, including two confirmed partial responses (PR, > 30% tumor shrinkage) and seven minor responses (MR, > 10% and <30% tumor shrinkage) using RECISTv1.1 criteria. PFS in the Phase 1b cohort has not been reached with a median follow up exceeding 15 weeks at the data cutoff.
These data include the following: Nineteen patients in the Phase 1b arm of the trial are evaluable for efficacy. Safety findings (n=22) are in line with those data reported in the Phase 1a cohort. Three patients enrolled were not evaluable for efficacy at the data cutoff (2 patients not eligible and 1 patient not having reached an initial follow up scan) but having received one dose of drug are considered evaluable for safety; The baseline baseline data data from the Phase 1b cohort is expected in the first half of 2026.
