Potential for efficacy of the oncolytic herpes simplex virus 1716 in patients with oral squamous cell carcinoma

Background. Herpes simplex virus (HSV) 1716 is a selectively replicating oncolytic virus. Our objective was to assess the potential efficacy of HSV1716 in patients with oral squamous cell carcinoma (SCC) by intratumoral Injection. Methods. Twenty patients with oral SCC had a single intratumoral injection of HSV1716 at a dose of 105 pfu (plaque forming unit) or 5 X 105 pfu. Injections were done at 1, 3, or 14 days before surgical resection, The tumors were assessed for evidence of viral replication and necrosis. Immunologic response to virus and toxicity was also assessed. Results. Intratumoral injections were well tolerated with no adverse effects. Evidence of biological activity was lacking, with no increase in detectable virus in tumor samples. Conclusion, Intratumoral injection of HSV1716 is safe but with little evidence for viral replication or efficacy. Further studies at higher doses are required to determine the potential efficacy of this virus in head and neck cancer. (c) 2008 Wiley Periodicals, Inc.