Retrospective evaluation of fidaxomicin versus oral vancomycin for treatment of Clostridium difficile infections in allogeneic stem cell transplant

Objective/background: Clostridium difficile infection (CDI) is a potential complication during hematopoietic stem cell transplantation (HSCT), and no specific recommendations exist regarding treatment of CDI in allogeneic SCT patients. Use of metronidazole and oral vancomycin has been associated with clinical failure. Fidaxomicin has previously been found noninferior to the use of oral vancomycin for the treatment of CDI, and no studies have compared the use of oral vancomycin with fidaxomicin for the treatment of CDI in allogeneic SCT. Methods: This retrospective chart review included 96 allogeneic SCT recipients who developed CDI within 100 days following transplantation. Participants were treated with oral vancomycin (n = 52) or fidaxomicin (n = 44). The primary outcome was clinical cure, defined as no need for further retreatment 2 days following completion of initial CDI treatment. Secondary outcomes were global cure, treatment failure, and recurrent disease. Results: No differences in clinical cure were observed between patients receiving oral vancomycin or fidaxomicin (75% vs. 75%, p = 1.00). Secondary outcomes were similar between oral vancomycin and fidaxomicin in regards to global cure (66% vs. 67%, p =.508), treatment failure (28% vs. 27%, p =.571), and recurrent disease (7% vs. 5%, p =.747). In a subanalysis of individuals that developed acute graft-versus-host disease following CDI, the difference in mean onset of acute graft-versus-host disease was 21.03 days in the oral vancomycin group versus 32.88 days in the fidaxomicin group (p =.0031). Conclusion: The findings of this study suggest that oral vancomycin and fidaxomicin are comparable options for CDI treatment in allogeneic SCT patients within 100 days following transplant.