A phase I trial of intravenous vesicular stomatitis virus expressing thyroidal sodium iodide symporter (NIS) and human interferon beta (hIFNβ) in metastatic or recurrent endometrial cancer.

This Phase I trial tested whether intravenous oncolytic vesicular stomatitis virus engineered to express human interferon beta and thyroidal sodium iodide symporter (VSV-hIFNβ-NIS) is safe and tolerable in patients with stage IV or recurrent endometrial cancer. Across 21 patients, dose-limiting toxicities occurred at two dose levels, but the maximum tolerated dose was not reached because of manufacturing limits, and the most common treatment-related effects were transient hematologic changes, liver enzyme elevations, and cytokine release syndrome. Although objective responses were rare, four patients who later received immune checkpoint inhibitors had durable stable disease, suggesting potential for combination with immune checkpoint blockade.