Management of Xerostomia Following Radiotherapy: A clinical trial of a novel emulsion for potential use as a saliva substitute

Abstract

Aim: Researchers have recently developed a novel oily formulation for potential us as a saliva substitute. The aim of this randomised, cross-over study is to compare this new formulation to a currently available saliva substitute and a control of water on measures of mastication, subjective feeling of oral dryness and product acceptability. Methods: Forty participants treated with radiotherapy to the head and neck region and experiencing xerostomia were selected to participate in the trial. Each participant trialled all three products in a randomised order. The effect of each product was measured using the Test of Masticating and Swallowing Solids (TOMASS), the shortened Xerostomia Inventory (SXI) and a questionnaire designed to test the patient acceptability of each product. Outcome data were gathered in a single session after the first administration of each product to evaluate immediate effects, and after seven days of use to evaluate longer-term effects. Statistical analysis consisted of repeated measures analysis of variance and mixed effect models. Results: There was no effect of any of the three formulations either with immediate or cumulative use on any of the TOMASS measures (p > 0.05). Application of the novel emulsion resulted in a clinically small but significant improvement in SXI score compared to baseline (p<0.01), however application of methylcellulose (p=0.21) and water (p=0.81) resulted in no significant difference compared to baseline values. There was no difference in participant acceptability between the 3 products (p=0.32). Conclusion: The novel oily emulsion shows no clinically significant benefit over two existing products for relief of xerostomia. Indeed, none of the three products demonstrated significant change in patient outcomes.