Prevention of Recurrent C. Difficile Infection Study With AZD5148 Monoclonal Antibody

Approximately 230 participants will be enrolled and randomized 1:1 to receive a single dose of either AZD5148 or placebo (normal saline). Route of administration (intramuscular or intravenous push) will be according to the Investigator's choice. Stratification will be based on geographical region. Study details include: * Up to 2 site visits for confirmation of eligibility and dose administration, including stool sample collection; * Up to 7 planned visits; * Contacts initiated by site staff -weekly, later monthly follow up; * Electronic diary completion.