Anti-PD-1 scFv was inserted into OVH (γ34.5 and ICP0 deleted) to generate OVH-aMPD1, and examined in a bilateral Hepa1–6 liver cancer model, where it was significantly better at inhibiting the tumor growth of both injected and non-injected tumors compared to OVH when large tumors were treated but not small ones. The gene discussed is AMPD1; the disease is neoplasm.