GLV-1h68 exhibits significant oncolytic effects in human head and neck squamous cell carcinoma in vitro. Six cell lines were infected with GLV-1h68 at varying MOIs (0.01, 0.1, 1) and lactate dehydrogenase assays performed for 6 days to assess cell viability. Untreated cells were considered 100% viable. The y-axis designates percentage viability, and the x-axis designates the day post-infection. All six cell lines sustained significant cytotoxicity at an MOI of 1, four cell lines were sensitive at an MOI of 0.1, and three cell lines demonstrated an exquisite sensitivity to GLV-1h68 even at a very low MOI of 0.01.