Fidaxomicin Well-Tolerated in Pediatric C diff Cases

Fidaxomicin was as successful as vancomycin for the treatment of pediatric Clostridioides difficile (C diff) infection, according to a new report published in Clinical Infectious Diseases.

Investigators from St. Jude Children’s Research Hospital randomized 142 pediatric C diff patients in order to measure confirmed clinical response 2 days after the end of treatment. The patients were all under the age of 18 years and were randomized to receive 10 days treatment with fidaxomicin (suspension or tablets, twice daily) or vancomycin (suspension or tablets, 4 times daily). Patients were enrolled from 39 sites across the United States, Canada, and Europe and were diagnosed with C diff using standard criteria.

While fidaxomicin is associated with lower rates of recurrence than vancomycin in adult C diff cases, pediatric data is limited, the study authors explained.

“C diff is an important problem in pediatrics,” study author Joshua Wolf, PhD, MBBS, from the St. Jude’s Department of Infectious Diseases, explained to Contagion®. “It is especially important for children undergoing treatment for cancer; their immune systems are affected by cancer and chemotherapy, so they frequently need antibiotics which increase the risk of C diff, and they are prone to life-threatening infections.”

Specifically, for example, Wolf explained that children with leukemia and C diff have a higher chance of dying than those without. In previous research, Wolf and his team showed that preventing infections with the antibiotic levofloxacin reduced C diff risk for pediatric leukemia patients.

In this study, though, the team found confirmed clinical response after 2 days after the end of treatment was 77.6% among fidaxomicin-treated pediatric cases. In vancomycin-treated pediatric C diff cases, that rate reached merely 70.5%, the investigators determined.

Furthermore, the rate of global cure—confirmed clinical response without C diff recurrence—was higher in patients treated with fidaxomicin compared to vancomycin (68.4% vs. 50.0%, respectively).

“This study is useful because it shows that fidaxomicin is safe and effective in pediatrics and might reduce the risk of treatment failure or relapse of C diff,” Wolf added. “We did a careful subgroup analysis of immunocompromised children (including those receiving cancer treatment) that showed that the reduction in risk of relapse from fidaxomicin was about the same as for other kids, but that initial response was about the same.”

C diff recurrence before the end of the study was seen in 11.8% of fidaxomicin-treated patients who achieved confirmed clinical response, the study authors said, compared to 29% of vancomycin-treated patients.

Treatment-emergent adverse events (TEAEs) were experienced at a similar rate between the study cohorts, the investigators wrote. Drug-related TEAEs were seen in 7.1% of fidaxomicin patients and 11.4% of vancomycin-treated patients. There were 2 discontinuations that were not included in the analysis; these patients withdrew due to moderate colitis (fidaxomicin) and severe vomiting (vancomycin).

Additionally, 3 deaths occurred in the fidaxomicin group during the study period and 2 deaths occurred in the vancomycin group shortly after the conclusion of the study period. The study authors noted that none of these deaths were C diff- or treatment-related.

“Fidaxomicin for the treatment of C diff infection in children and adolescents was well tolerated, and fidaxomicin was associated with a lower risk of treatment failure or recurrence than vancomycin,” the study authors concluded.