Impact of adjunct bezlotoxumab for preventing Clostridioides difficile infection recurrence in patients post - hematopoietic stem cell transplantation.

Background: Patients post hematopoietic stem cell transplant (HSCT) are highly susceptible to Clostridioides difficile infection (CDI). Exposure to antibiotic treatment, chemotherapeutic disruption to bacterial microbiome, immunosuppressive therapy, and prolonged hospitalizations synergistically contribute to the risk of CDI and its recurrence. The purpose of this study is to assess if the adjunctive administration of bezlotoxumab decreases the rate of recurrent CDI in patients post-HSCT.

Study design: This retrospective cohort study included patients post allogeneic or autologous HSCT with CDI who were 18 years of age or older. The first cohort included patients who received standard-of-care (SOC) treatment for CDI. The second cohort included patients who received standard of care treatment for CDI in addition to bezlotoxumab. The primary objective was the proportion of patients with recurrence of CDI within 12 weeks of initial diagnosis after treatment with bezlotoxumab plus SOC compared with controls receiving SOC alone.

Results: The primary outcome occurred in 2.7% of patients in the bezlotoxumab plus SOC group, and 7.1% of patients in the SOC alone group. Results of the primary outcome were not statistically significant between groups. No difference in CDI recurrence occurred between the two groups (5.4% vs 7.1%) at 6 months. Bezlotoxumab administration was well-tolerated with no documented adverse reactions.

Conclusion: In conclusion, the use of bezlotoxumab did not lead to statistically significant decreases in CDI recurrence in patients post-HSCT. Future studies should be conducted with a larger number of HSCT patients receiving bezlotoxumab to provide supporting evidence of its role in reducing CDI recurrence.