The rationale for combining FilC and PD-1 inhibition within a single oncolytic vaccinia virus platform is therefore twofold: (i) to exploit the selective tumor lysis and immunogenic cell death induced by the vaccinia virus, and (ii) to deliver dual checkpoint blockade directly into the tumor microenvironment, enhancing local T cell activation while minimizing systemic exposure. The gene discussed is PDCD1; the disease is neoplasm.