Compound staphylococcal lysostaphin for oral mucositis prophylaxis in hematopoietic stem cell transplantation recipients: a non-inferiority randomized trial.

BACKGROUND: Chlorhexidine mouthrinse offers a cost-effective approach to preventing oral mucositis (OM) in anti-tumour treatment, yet it might cause tooth discoloration, unpleasant taste, and pain. To compare compound Staphylococcal lysostaphin (CSL) mouthrinse to chlorhexidine mouthrinse in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. METHODS: This randomised, controlled, non-inferiority clinical trial (NCT06791746) randomised adult patients who were scheduled for myeloablative conditioning and allo-HSCT to receive OM prophylaxis using CSL mouthrinse or chlorhexidine mouthrinse. The primary endpoint was the cumulative incidence of oral mucositis, with a non-inferiority margin of 15%. RESULTS: Among 196 participants in the CSL mouthrinse group and 197 in the chlorhexidine mouthrinse group, ninety-four (48.0%) and 105 (53.3%) developed OM, respectively. The absolute risk difference was -5.3% (95% CI: -15.6, 4.7), with a upper limit of 95% CI did not exceed the non-inferiority margin. The average pain score was significantly lower with CSL mouthrinse (0.45 ± 1.06 vs. 0.85 ± 1.39, P = 0.002), supported by the analysis of distribution of pain score (P < 0.001). The time to OM onset and cumulative days with OM were comparable between the two groups (both P > 0.05). CONCLUSIONS: CSL mouthrinse had non-inferior prophylactic efficacy in reducing OM occurrence in patients undergoing myeloablative conditioning allo-HSCT compared to chlorhexidine mouthrinse, with less pain intensity.