Safety & Efficacy Study of Benzydamine Oral Rinse for the Treatment of Oral Mucositis (Mouth Sores) Resulting From Radiation Therapy for Cancer of the Oral Cavity, Oropharynx, or Nasopharynx

This is a multicenter, double-blind, randomized, vehicle-controlled study including an open-label standard of care arm, to determine the effectiveness and safety of benezydamine hydrochloride 0.15% oral rinse as compared with vehicle oral rinse, and vehicle oral rinse as compared to the care normally used in the treatment of radiation-induced oral mucositis. The hypotheses are that benzydamine hydrochloride 0.15% oral rinse is better than vehicle oral rinse as measured by the proportion of patients reaching a WHO mucositis score of 3 by 5500 cGy and vehicle is no worse than the standard of care as measured by the proportion of patients reaching a WHO mucositis score of 3 by 5500 cGy. Patients receiving benzydamine hydrochloride 0.15% or vehicle double-blind oral rinses will place 15 mL in the mouth for 2 minutes, gargling for a few seconds at the beginning and end of the rinse, and then expectorate the entire dose. Dosing with oral rinses will be every 2 - 3 hours while awake for a minimum of 4 times daily to a maximum of 8 times per day. Double-blind oral rinses will continue daily throughout the duration of the subjects radiation treatment regimen plus 2 additional weeks