Oral Vancomycin for Prevention of Recurrent Clostridioides difficile Infection: A Randomized Clinical Trial

Area of Science:

• Infectious Diseases
• Clinical Trials
• Microbiology

Background:

• Systemic antibiotic use is a significant risk factor for recurrent Clostridioides difficile infection (CDI).
• Oral vancomycin is increasingly used for secondary prophylaxis against recurrent CDI, but its efficacy is uncertain.

Purpose of the Study:

• To evaluate the efficacy of oral vancomycin prophylaxis compared to placebo in preventing recurrent CDI.
• To assess the incidence of recurrent CDI during and 8 weeks after study treatment.

Main Methods:

• Phase 2, placebo-controlled, double-blind randomized clinical trial involving adults treated for CDI within 180 days and receiving systemic antibiotics for another indication.
• Participants received either oral vancomycin (125 mg once daily) or placebo during and for 5 days after antibiotic treatment.
• Primary outcome: recurrent CDI incidence; Secondary outcome: vancomycin-resistant Enterococcus (VRE) carriage.

Main Results:

• Recurrent CDI occurred in 43.6% of the vancomycin group vs. 57.1% in the placebo group (absolute difference: -13.5%; 95% CI, -35.1% to 8.0%).
• Adverse events were similar between groups (69.2% vancomycin vs. 64.3% placebo).
• VRE carriage was significantly higher in the vancomycin group (50.0%) compared to placebo (24.0%) (P=.048).

Conclusions:

• The study suggests a potential trend towards reduced recurrent CDI with oral vancomycin, but this did not reach statistical significance.
• The trial was underpowered to draw firm conclusions on vancomycin's efficacy for preventing recurrent CDI.
• Increased vancomycin-resistant Enterococcus carriage is a notable finding requiring consideration.