N-acetylcysteine mouthwash for prevention of oral mucositis in hematopoietic cell transplant recipients: a double-blind randomized controlled trial

Oral mucositis (OM) is a frequent and clinically important toxicity of conditioning therapy for hematopoietic cell transplantation (HCT). This trial evaluated whether prophylactic N-acetylcysteine (NAC) mouthwash reduces the incidence and severity of OM in HCT recipients.

In this single-center, double-blind, randomized, placebo-controlled trial, adults undergoing autologous or allogeneic HCT were assigned 1:1 to NAC mouthwash (600 mg every 6 h; 2400 mg/day) or matching placebo from the first day of conditioning until day +14 after transplantation or neutrophil engraftment, whichever occurred first. OM was assessed daily using the World Health Organization (WHO) Oral Toxicity Scale. The primary outcomes were the incidence of any OM and severe OM (WHO grades 3-4). Safety and exploratory predictors of OM were also evaluated.