Effectiveness, Tolerability, and Safety of Ectoine-Containing Mouthwash Versus Those of a Calcium Phosphate Mouthwash for the Treatment of Chemotherapy-Induced Oral Mucositis: A Prospective, Active-Controlled, Non-interventional Study.

Introduction: Oral mucositis is a frequent complication of cancer chemotherapy and radiotherapy. Ectoine is a natural extremolyte that can stabilize biological membranes and counteract inflammatory reactions. This study investigated ectoine-containing mouthwash for the prophylaxis and the treatment of oral mucositis. Its effectiveness, tolerability, and safety were compared to those of the local standard-of-care calcium phosphate mouthwash.

Methods: This prospective, active-controlled, observational study was conducted in two study centers in Hungary from January 2016 to October 2017. Sixty patients undergoing chemotherapy were to be recruited and allocated to one of three treatment arms: prophylactic treatment with ectoine (20 patients), active treatment with ectoine (20 patients), or calcium phosphate (20 patients). The study lasted 21 days, comprising four visits on day 0, day 7, day 14, and day 21.

Results: In all, 45 patients were included in the study (prophylactic ectoine, 10 patients; active ectoine, 20 patients; calcium phosphate, 15 patients). In the prophylactic ectoine group, few mucositis symptoms of mild or moderate severity occurred throughout the study. In the active ectoine and the calcium phosphate groups, symptoms of mild and moderate severity at inclusion were reduced significantly after 14 days of treatment and were mostly resolved at the end of the study. The difference between the active ectoine and the calcium phosphate groups was not significant. According to patients' assessments, ectoine mouthwash was more effective and tolerable than calcium phosphate mouthwash.

Conclusions: Ectoine mouthwash is safe, well tolerated, and effective for the active treatment of oral mucositis following chemotherapy. Its effectiveness is comparable to that of calcium phosphate. Patients prefer ectoine mouthwash to calcium phosphate mouthwash.

Trial Registration Number: NCT02816515.

Funding: Bitop AG (Dortmund, Germany). Plain language summary available for this article.