Theriva Biologics has finalized a Phase 3 trial plan with the FDA to test zabilugene almadenorepvec combined with standard chemotherapy as a first-line treatment for metastatic pancreatic cancer. The trial follows promising Phase 2b results in 96 patients, which showed improved outcomes compared with chemotherapy alone: overall survival increased to 10.8 months versus 8.6 months, progression-free survival rose to 7.0 months versus 4.6 months, and the duration of response more than doubled to 11.2 months versus 5.4 months.
The Phase 3 study will be randomized, double-blind, and placebo-controlled, with overall survival as the primary endpoint. It will use innovative “macrocycle” dosing, allowing repeated VCN-01 treatments, and an adaptive design that permits early efficacy checks or sample size adjustments.
VCN-01 is an engineered virus that selectively targets tumor cells and degrades hyaluronan, a barrier in pancreatic tumors that blocks chemotherapy. Side effects like fever, flu-like symptoms, and nausea were temporary and usually milder after the second dose. With Orphan Drug and Fast Track status, regulatory agencies indicated that a single successful Phase 3 trial could support full approval.