Clostridium difficile vaccine

A *Clostridium difficile* vaccine is an investigational immunization designed to prevent infection by the bacterium *Clostridioides* (formerly *Clostridium*) *difficile*, a major cause of antibiotic-associated diarrhea and colitis. Several candidates have been developed targeting the primary virulence factors of *C. difficile*—namely toxins A (TcdA) and B (TcdB)—using various platforms such as genetically detoxified toxoid vaccines and mRNA-lipid nanoparticle vaccines. The most advanced candidate, PF-06425090 from Pfizer, is a recombinant toxoid-based vaccine that induces neutralizing antibodies against toxins A and B but did not meet its primary efficacy endpoint in phase 3 trials for prevention of *C. difficile* infection in at-risk adults[3][5][6]. Other approaches include multivalent mRNA-LNP vaccines targeting both toxins and additional virulence factors; these have shown robust immune responses and protection in animal models[8]. No *C. difficile* vaccine has been approved as of April 2025[1].

Brand names

CDIFFENSE

Other names

C. difficile vaccineClostridioides difficile vaccine