#1606 Topical Bioadhesibve (BiAD) Antioxidants Reduce the Severity of Experimental Radiation-Induced Oral Mucositis. JM Blonder, J Etter, A Samaniego, W Schauer, EG Frey, S Sonis, GJ Rosenthal; RxKinetix, Inc., Louisville, CO; Biomodels, LLC, Wellesley, MA, Brigham & Women’s Hospital, Boston, MA. Oral mucositis is a common and debilitating side effect of antineoplastic radiation and drug therapy. While the precise mechanism(s) responsible for this condition are not completely defined, significant advances have been made in understanding its underlying pathogenesis. Considering the involvement of reactive oxygen species(ROS) in mediating other manifestations of chemotherapy or radiation toxicity, it seems likely that ROS play a role in the initiation and progression of mucosal injury. In the present study, the topical application of the antioxidant, N-acetyl-L-cysteine (NAC) was tested for its ability to attenuate the course of radiation-induced oral mucositis in an established hamster model. Golden Syrian hamsters were divided into groups of 8. Following anesthesia, the left buccal pouch mucosa (BPM) was everted and radiated with a single 40Gy (RT). This regimen consistently produces clinically significant ulcerative mucositis equivalent to that observed in humans (NCI-CTC score of 3 or 4). Test and control formulations (NAC, NAC in a BiAD (ProGelz), vehicle control, water control) were topically applied to the BPM thrice daily beginning the day (d) prior to RT and continuing for 30 d. The BPM was photographed on alternate days from d6 to d30. The resulting photographs were randomly numbered and scored in blinded fashion, using a 6 point scale in which 0=normal mucosa, 3=ulcerative mucositis, and 5=severe, confluent ulcerative mucositis. While NAC alone demonstrated efficacy (peak score 2.8 vs control 3.5) NAC in BiAD was more effective (peak 2.2) These data demonstrate the potential involvement of ROS in mediating oral mucositis, and suggest that the use of topical application of antioxidant (NAC) in a BiAD formulation may provide a new approach for intervention. Hard for patients to tolerate at current regimen Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.