Natural killer (NK) cells are cytotoxic lymphocytes of the innate immune system that are responsible for direct and indirect cytolytic killing of virally-transformed and/or cancer cells. Harnessing NK cells in cancer immunotherapy therefore, provides a direct cytotoxic effect on cancer cells which further stimulates further downstream adaptive anti-tumor immune responses against the cancer. In order to effect a more targeted killing of these tumor cells, using a monoclonal antibody (mAb) to direct these NK cells to the target site is feasible, provided a specific tumor antigen can be identified. In nasopharyngeal Carcinoma (NPC) and head and neck squamous cell carcinoma (HNSCC) where epidermal growth factor receptor (EGFR) is ubiquitously expressed, combining NK cell therapy with cetuximab (a chimeric mouse/human anti-EGFR monoclonal antibody) to direct these NK cells against these EGFR tumor targets is possible. In this study, we seek to enhance the antitumor activity of cetuximab to treat EGFR-positive head and neck cancers by combing infusion of activated expanded autologous NK cells with cetuximab. Patients selected for this trial are those with refractory NPC and HNSCC where no feasible therapeutic options are available. This is a lead-in phase I followed by a phase II study. The phase I study will enroll 9 patients and will test the feasibility and safety of this combination strategy and determine the tolerated dose of NK cell infusion (1x1^06/kg or 1x10^7/kg NK cells) in adult EGFR positive NPC and HNSCC patients. For the first 3 patients, each new patient will only be enrolled at least 3 weeks after treatment of the preceding patient to allow sufficient time to monitor toxicities. Initial phase of treatment consists of 7 weeks of cetuximab monotherapy. At week 8, clinical evaluation will be done to determine patients who are suitable to continue this study with NK cell therapy, based on the severity of toxicities encountered. Eligible patients will undergo apheresis (Day -10) to harvest NK cells. The collected NK cells will be expanded and activated in the laboratory. During cycle 1, cetuximab will be given on day 1 with subcutaneous IL-2 (three times per week for 2 weeks); followed by expanded NK cells on day 2. The purpose of IL-2 is to sustain activity of these NK cells in-vivo. Cetuximab will be administered weekly for additional 2 weeks following the NK cell infusion during cycle 1. For cycle 2 and 3, cetuximab monotherapy will be administered every 21 days. Clinical evaluation will be performed upon completion of cycle 3. Patients with stable disease or with partial response will be allowed to continue with a second NK infusion dose as per cycle 1, followed by additional 2 more cycles of cetuximab monotherapy (every 21 days).~.
This study aims to determine the safety and efficacy of expanded activated autologous NK cells administered after cetuximab in patients with EGFR-positive nasopharyngeal carcinoma or head and neck squamous cell carcinoma.