Azithromycin for Prevention of Graft-Versus-Host Disease: A Randomized Placebo-Controlled Trial

Background: allogeneic hematopoietic stem cell transplantation has been used widely to treat various types of malignant and non-malignant disorders. graft-versus-host disease is one of the main complications of this procedure which is associated with considerable mortality and affects quality of life. despite careful selection of hla-matched donors and implementing immunosuppressive therapy, the incidence rate of graft-versus-host disease remains high. macrolide antibiotics are well-known immunomodulatory agents and have been effective as prophylaxis for graft-versus-host disease in preclinical studies.materials and methods: ninety-six adult patients with acute leukemia were recruited into a double-blind, randomized, placebo-controlled trial. all patients were first-time transplant candidates for a full-matched related or unrelated donor. patients were allocated to receive azithromycin 500 mg daily (n=48) or placebo (n=48) from day -6 to +12. all patients received high-dose chemotherapy, standard immunosuppressive regimen and supportive care according to institutional protocols.results: the incidence of acute graft-versus-host disease grade iii-iv and chronic graft-versus-host disease garde i-iii was not significantly different between the two study arms. oral mucositis grade 1-3 occurred in significantly lower number of patients in the azithromycin group compared with placebo.conclusion: based on the results of this study, protective effect of azithromycin on graft-versus-host disease could not be demonstrated.