1. Subjects will be enrolled if they have HPV -16 and/or HPV-18 positive HNSCCa, and have completed chemoradiation therapy . Adequate tissue must be available to perform immunological correlates studies. Confirm ation of HPV -16 and/or HPV - 18 positivity is required prior to first dose of immunotherapy. 2. Subjects will be followed for tumor status as per normal institutional standard of care. 9 Date: 8 April, 2016 v 2.1 INO-3112 UPCC # 39313 / HPV -005 Inovio Pharmaceuticals, Inc Clinical Protocol Study Endpoints : Primary Endpoints: Safety and tolerability based on standard laboratory and clinical adverse event monitoring. 1. Adverse events will be measured and graded according to “Common Terminology Criteria for Adverse Events (CTCAE)”, NCI version 4.03 issued by the US Department of Health and Human Services. 2. Frequency and severity of i njection site reactions including administration site pain, skin erythema, induration, bleeding tenderness and infection. Secondary Endpoints: Immune response after immunotherapy based on correlative measures. 1. Measure HPV -16 and HPV -18 spec ific antibody levels. 2. Using Antigen -specific IFN -γ ELISpot assays, determine the number of antigen- specific spot forming units (SFU) in response to stimulation with HPV-16 and HPV-18. 3. Evaluate c ytotoxic T cells in response to HPV specific immunotherapy by flow cytometry. 4. Evalua te tumor infiltrating lymphocytes (TILs) by Immunohistochemistry (IHC) o n pre-surgical and surgical samples. 5. Evaluate phenotypes of cultured TILs. Exploratory Endpoints: Clinical response criteria as determined by: 1. Any e vidence of anti- tumor response as assessed by the Investigator 2. Progression f ree survival 10 Date: 8 April, 2016 v 2.1 INO-3112 UPCC # 39313 / HPV -005 Inovio Pharmaceuticals, Inc Clinical Protocol Study Population: Inclusion Criteria 1. Signed and dated written Ethics Committee approved informed consent.