Fidaxomicin, Vancomycin Provide Similar C Difficile Initial Cure, Mortality Rates

Clostridioides difficile (C difficile) infection therapies fidaxomicin and vancomycin do significantly differ in patient outcomes for initial cure nor mortality, according to findings from a new systematic literature review and meta-analysis.

In new data presented at the Making A Difference in Infectious Disease (MAD-ID) 2021 Annual Meeting, a team of Rhode Island-based investigators reported clinical outcome similarities between the 2 agents across patients treated in 3 different randomized, controlled trials.

That said, the report—presented by J. Xin Liao, PharmD, of the Providence Veterans Affairs Medical Center—did show differentiations in C difficile recurrence among fidaxomicin and vancomycin. The outcome may indicate a more viable first-line treatment strategy to reduce infection recurrence, a key burden among affected C difficile patients.

Current national guidelines recommend either fidaxomicin or vancomycin as the primary treatment of both initial and recurrent C difficile infection, Liao and colleagues wrote. The team sought to interpret opportunities for preference of 1 agent over the other, in order to optimize treatment strategies.

Investigators conducted a systematic literature review of relevant clinical trial databases through until February 2021 for randomized, controlled studies comparing guideline-recommended regimens of vancomycin and fidaxomicin for treating C difficile in adult patients.

They sought primary endpoints of initial cure 2 days following treatment, as well as infection recurrence and mortality at 1 month post-treatment. Their meta-analysis of eligible trials was conducted via random effects modeling.

The team’s final assessment included 3 randomized, controlled trials comprised of 1359 total patients; 668 were treated with fidaxomicin, and 691 were treated with vancomycin. Mean patient age during study was 64.4 years old. More than one-third (38.9%) of patients were classified with severe C difficile infection.

Initial cure was prevalent in 87.2% of patients treated with fidaxomicin, versus 86.5% of patients treated with vancomycin. Mortality at 1 month occurred in 5.8% and 5.9% of treated patients, respectively.

Investigators did observe an approximate 42% decrease in C difficile recurrence likelihood in patients treated with fidaxomicin (RR, 0.58; 95% CI, 0.45 – 0.75; P <.0004) versus vancomycin.

Liao and colleagues indeed concluded that the first line therapies did not significantly differ in initial cure or short-term mortality outcomes for C difficile infection treatment.

“However, fidaxomicin was associated with a lower risk of CDI recurrence compared to vancomycin one-month post-treatment,” they wrote. “These results indicate fidaxomicin may be preferred first-line over vancomycin in minimizing CDI recurrence.”