The clinical effectiveness of Fidaxomicin compared to Vancomycin in the treatment of Clostridioides difficile infection, a single center real-world experience

Background: The use of fidaxomicin is recommended as first line therapy for all patients with Clostridioides difficile infection (CDI). However, real-world studies have shown conflicting evidence of superiority.

Methods: We conducted a retrospective single center study of patients diagnosed with CDI between 2011-2021. A primary composite outcome of clinical failure, 30-day relapse or CDI-related death was used. A multivariable cause specific Cox proportional hazards model was used to evaluate fidaxomicin compared to vancomycin in preventing the composite outcome. A separate model was fit on a subset of patients with C. difficile ribotypes adjusting for ribotype.

Results: There were 598 patients included, of whom 84 received fidaxomicin. The primary outcome occurred in 8 (9.5%) in the fidaxomicin group compared to 111 (21.6%) in the vancomycin group. The adjusted multivariable model showed fidaxomicin was associated with 63% reduction in the risk of the composite outcome compared to vancomycin (HR = 0.37, 95% CI 0.17-0.80). In the 337 patients with ribotype data after adjusting for ribotype 027, the results showing superiority of fidaxomicin were maintained (HR = 0.19, 95% CI 0.05-0.77).

Conclusion: In the treatment of CDI, we showed that real-world use of fidaxomicin is associated with lower risk of a composite endpoint of treatment failure.