Effects of bio-adhesive barrier-forming oral liquid (Episil®) on pain due to radiation-induced oral mucositis in patients with head and neck cancer: A randomized crossover trial

Background Bio-adhesive barrier-forming oral liquid (Episil®) is a recently developed medical device for the management of pain caused by oral mucositis associated with cancer radiotherapy or chemotherapy. The purpose of this study was to evaluate the effectiveness of this material for the relief of pain resulting from radiation-induced oral mucositis in patients with head and neck cancer who are undergoing radiotherapy.Methods This was a randomized, open-labeled, crossover trial investigating the pain relief effects of Episil® using dexamethasone ointment as a control. Fifteen patients who had mild or moderate pain due to radiation induced oral mucositis were randomly assigned to two groups: group A applied dexamethasone ointment once on the first day, had a wash-out period on the second day, and used Episil® once on the third day. Conversely, group B used Episil® on day 1, followed by a wash-out period on day 2 and dexamethasone ointment on day 3. The effectiveness of the test drug/materials on the relief of pain was compared.Results One patient reported nausea immediately after application of Episil® and was therefore excluded from the analysis of pain relief. Dexamethasone ointment relieved pain in 85.7% of patients compared to 71.4% with Episil® (p = 0.682). Nine patients wished to continue dexamethasone ointment after the study while only five wished to continue Episil®.Conclusions Our findings suggest that the pain relief effect of Episil® is comparable to or less than that of dexamethasone ointment. Larger follow-up studies are needed to verify these findings.Trial registration:The study protocol was registered in the Japan Registry of Clinical Trials (jRCT) on March 3rd, 2019 (jRCTs072180039).