MVR-T3855

MVR-T3855 is a preclinical **mouse surrogate oncolytic herpes simplex virus 1** developed by ImmVira to model the activity of MVR-T3011 in immunocompetent murine systems. It is described as the mouse surrogate of MVR-T3011, an intravenously deliverable, genetically modified, replication-competent oncolytic HSV-1 engineered in the corresponding human program to express **interleukin-12** and an **anti-PD-1 antibody**. In reported nonclinical studies, intravenous administration of MVR-T3855 significantly prolonged survival in mouse models of melanoma lung metastasis, orthotopic lung cancer, and orthotopic hepatocarcinoma, and also delayed malignant ascites or peritoneal effusion in liver cancer models. The program appears to function through tumor-selective viral replication and local immunostimulation, but MVR-T3855 itself has only been described publicly as a murine surrogate research agent rather than a clinical or commercial product.