Comparative effectiveness of different therapies for Clostridioides difficile infection in adults: a systematic review and network meta-analysis of randomized controlled trials

Background Clostridioides difficile infection (CDI) is a leading cause of healthcare-associated diarrhea, with substantial morbidity and mortality. CDI is a severe and growing problem with numerous treatment options. We evaluated the effectiveness of all therapies in recurrent and non-recurrent infections and their prevention. Methods This network meta-analysis and systematic review of randomized controlled trials (RCTs) compared all CDI therapies and preventions. We included RCTs published until 19 August 2024 and focused on adult population. We performed a systematic search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials. Inclusion criteria were patients: adults (>16) treated against CDI; study type: randomized controlled trial; outcome: cure rate, recurrence or effectiveness of prevention. Any publication not meeting all criteria was considered to be ineligible and excluded. We applied random-effects meta-analysis using frequentist methods. We reported our main results as odds ratios (as a symmetric effect size measure, OR) with 95% confidence interval (95% CI). We used the Cochrane risk-of-bias tool to assess the risk of bias. Our study protocol was preregistered in PROSPERO (CRD42022371210). Findings We assessed 73 RCTs with 28 interventions, involving 27,959 patients (49.2% female) in five networks. Fecal microbiota transplantation (FMT) was the most effective treatment in terms of the cure rate overall (P-score: 0.9952) and in recurrent cases (P-score: 0.9836). In recurrent cases, fidaxomicin (P-score: 0.6734) showed significantly greater effectiveness than vancomycin (P-score: 0.3677) and tolevamer (P-score: 0.0365). For non-recurrent CDI treatments ridinilazole, fidaxomicin, FMT and nitazoxanide were equally effective. Ridinilazole (P-score: 0.7671) and fidaxomicin (P-score: 0.7627) emerged as the most effective in preventing recurrence. Probiotics were not effective in preventing CDI, since network meta-analyses did not show significant differences between probiotics and placebo. In probiotics' subgroups pairwise meta-analyses Lactobacillaceae proved to be significantly more effective in prevention than placebo. Oral and colonoscopic FMT administration methods were equally effective. The study-level aggregated risk of bias of the publications included ranged from low to high. We observed relevant heterogeneity among studies in therapeutic doses, treatment durations, and follow-up times.<br /> Interpretation The superiority of FMT in the treatment of CDI highlights the potential for increased use of FMT in clinical settings. Further research on optimizing FMT protocols and exploring its long-term safety and efficacy in larger samples is needed. Our findings suggest that the preventive use of probiotics might be questioned.