This study investigates a way to prevent the return of Clostridioides difficile infection, a type of infection in the gut that often causes severe diarrhea. The research aims to determine if a new medication can reduce how often the infection comes back after the initial treatment. The medication being tested is called AZD5148, which is a monoclonal antibody. A monoclonal antibody is a type of protein made in a laboratory that is designed to find and attach to specific targets in the body, such as the toxin B produced by the bacteria.

Participants in the study will receive either AZD5148 or a placebo. The medication will be given as an intravenous infusion, which means it is delivered directly into a vein through a needle or tube. This treatment is administered alongside standard care, which includes regular antibacterial drugs used to treat the current infection. During the study, individuals will be monitored to see if the infection returns within a specific period of time.