Current
drug treatment of
Clostridium difficile infection (CDI) focuses on
metronidazole and
vancomycin. Early studies showed equivalence, but more recent reports indicate that oral
vancomycin is preferred for serious CDI. Recent work has demonstrated a need for new drugs due to challenges with the NAP-1 strain, which appears to cause more refractory disease that is more likely to relapse. These two distinctive facets of treatment are the most challenging. This review discusses new agents in development:
antibiotics, probiotics, immune response products, and agents to bind C. difficile toxins. None are likely to be more effective than oral
vancomycin for acute
infection. However, several may be as effective, without causing relapse or promoting unnecessary
antibiotic use for multiple conditions. The greatest promise is with agents used to interrupt relapses. In this category the leading new agents appear to be
antibiotics (
rifaximin,
nitazoxanide, difimicin,
ramoplanin), toxin-binding agents (
tolevamer), probiotics (Saccharomyces -boulardii and Lactobacillus ramosus), and immune agents (
toxoid vaccine and hyperimmune
globulin). The drugs that appear most promising based on recent trials are
rifaximin,
tolevamer, and difimicin, which appear promising for reducing relapses.