Study Phase: 2 Indication: Metastatic and/or Recurrent Squamous Cell Carcinoma of the Head and Neck Primary Objective: To estimate the effect of administration of 9 mg/kg Q3W of panitumumab on the area under the curve (AUC) of total plasma cisplatin-derived platinum levels and the average concentration at steady state (Css) of 5-fluorouracil (5-FU) in subjects who are receiving cisplatin and 5-FU.