zabilugene almadenorepvec (VCN-01) in combination with gemcitabine/nab-paclitaxel -(VIRAGE2)

August 6, 2026: Theriva Biologics (NYSE: TOVX) announced first-patient dosing in VIRAGE2, a Phase 2a single-arm, open-label study of VCN-01 (zabilugene almadenorepvec) plus gemcitabine/nab-paclitaxel in newly diagnosed first-line metastatic pancreatic ductal adenocarcinoma (PDAC). The 6-patient proof-of-concept trial in Spain is testing more frequent repeated dosing of VCN-01 to refine a regimen for potential future pivotal Phase 3 development.

VIRAGE2’s primary objective is tolerability and pharmacodynamics of at least 3 VCN-01 doses given about 2 months apart; primary endpoints are adverse events and VCN-01 viral genome levels in blood. Secondary endpoints include objective response rate, duration of response, progression-free survival, overall survival, and anti-VCN-01 neutralizing antibodies. Enrollment is expected to finish in H2 2026, with initial pharmacodynamic and safety/tolerability data anticipated by Q3 2027.

The study follows the Phase 2b VIRAGE trial, where patients receiving 2 doses of VCN-01 plus standard chemotherapy showed improved overall survival, progression-free survival, and duration of response versus chemotherapy alone. The company said prior EMA scientific advice and FDA meeting feedback recognized the survival improvement and suggested that more frequent repeated dosing could potentially further improve outcomes.