A Phase 2 interventional study of AZD5148 and Placebo in Clostridioides Difficile Infection, sponsored by AstraZeneca. Recruiting at 117 sites in 14 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by AstraZeneca · Phase 2, Interventional, and Prevention
The purpose of this study is to evaluate the efficacy and safety of AZD5148 for prevention of recurrence of Clostridioides difficile infection in Individuals 18 years of age and above.
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:
251 studies on the registry are indexed under Clostridium Infections; 51 are open to participants now.
This study's planned enrollment of 230 is above the median of 64 across 185 interventional studies indexed under Clostridium Infections.
Browse Clostridium Infections studies →AstraZeneca is the lead sponsor of 3,499 studies on the registry; 270 are open to participants now.
Of its 368 completed or terminated interventional studies of FDA-regulated products, 178 (48%) have results posted.
Counted across the registry records on this site, refreshed daily.
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Participant must be ≥ 18 years of age at the time of signing the , capable of giving signed informed consent.
Participants with a qualifying C. difficile infection episode at the time of providing informed consent defined by:
Note: At the time of randomization and IMP administration, the participant must have started receiving the antibacterial drug therapy with a planned total treatment duration of at least 10 and at most 28 days at time of IMP administration. IMP can be administered at any point during the antibacterial drug therapy.
Body weight ≥ 35 kg
Exclusion Criteria:
Participants with a history of uncontrolled inflammatory bowel disease. Participants with a history of inflammatory bowel disease may be included if, in the opinion of the Investigator, their disease is clinically controlled and presenting symptoms are more likely attributable to CDI than to a flare of inflammatory bowel disease.
Participants with a non - CDI (C. difficile infection) condition such that the participant routinely passes loose stool (eg, patients with an ostomy)
Planned surgery for C. difficile infection within 24 hours of enrollment
Current toxic megacolon and/or small bowel ileus
Any history of total colectomy
Major gastrointestinal surgery as assessed by the Investigator (eg, significant bowel resection or diversion) within 90 days before enrollment (this does not include appendectomy or cholecystectomy)
Due to receive more than 28 days of antibacterial drug therapy for the qualifying C. difficile infection episode
Participants receiving a fecal microbiota transplant, fecal microbiota product, or live biotherapeutic product for the qualifying CDI episode, or planned administration during the 180 days after IMP administration.
Treatment with bezlotoxumab in the 180 days before IMP administration, are receiving or planned administration for the qualifying episode of CDI, or planned administration during the 180 days after IMP administration.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive a single dose A of AZD5148 administered via either intramuscular injection or intravenous push.
Drug: AZD5148
Participants will receive a single dose of placebo via intramuscular or intravenous push.
Other: Placebo
Participants will receive a single dose A of AZD5148 administered via either intramuscular injection or intravenous push.
Participants will receive a single dose of placebo (0.9% (w/v) sodium chloride for injection) administered via either intramuscular injection or intravenous push.
First occurrence of recurrence of C difficile infection
Recurrence of C difficile infection (rCDI) occurring after initial clinical cure (ICC) of the qualifying C difficile infection (CDI). CDI is defined as a history of diarrhea (\>=3 unformed stools, ie, type 6 or 7 stool on Bristol Stool Scale in \<=24 hours for 2 consecutive calendar days) accompanied by a positive stool test for C difficile toxin.
Time frame: Day 1 through day 91
Sustained clinical cure
Sustained clinical cure is defined as achieving ICC of the qualifying CDI and not having an rCDI event through Day 91. ICC is defined as clinical cure for the qualifying CDI episode with a duration of a minimum of 10 days and a maximum of 28 days of antibacterial drug therapy for CDI.
Time frame: Day 91
Duration of recurrent C difficile infection
Duration of the first occurrence of confirmed rCDI is calculated from the first day of diarrhea meeting the clinical symptom criteria until the date of clinical cure. Clinical cure is defined as \<=2 unformed stools (ie, type 6 or 7 stool on Bristol Stool Scale) in 24 hours for 2 consecutive calendar days after the end of antibacterial drug treatment for the CDI episode.
Time frame: Day 1 through Day 91
First occurrence of severe recurrent C difficile infection
Severe rCDI is defined as an rCDI event characterized by either: peripheral blood leukocytosis with leukocyte count \>15,000 cells/uL or serum creatinine level \>1.5 mg/dL.
Time frame: Day 1 through Day 91
First occurrence of fulminant recurrent C difficile infection
Fulminant rCDI is defined as a severe rCDI event with hypotension or shock, toxic megacolon, or ileus.
Time frame: Day 1 through Day 91
Severity of participant reported diarrhea symptoms
As reported by patient reported outcome (PRO) instrument for first occurrence of rCDI.
Time frame: Day 1 through Day 91
Duration of participant reported diarrhea symptoms
As reported by patient reported outcome (PRO) instrument for first occurrence of rCDI.
Time frame: Day 1 through Day 91
First occurrence of hospitalization due to recurrent C difficile infection
Hospitalization due to rCDI is defined as a confirmed rCDI event and a hospitalization related to the rCDI event.
Time frame: Day 1 through Day 91
Duration of hospitalizations due to recurrent C difficile infection
The sum of all hospitalization durations related to the first recurrent CDI that leads to hospitalization.
Time frame: Day 1 though Day 91
Occurrence of recurrent C difficile related mortality
rCDI related mortality is defined as a death related to rCDI as assessed by the Investigator.
Time frame: Day 1 through Day 91
Immediate adverse events
Adverse events with a start time within 1 hour post-IMP administration
Time frame: 1 hour post-IMP administration
Injection/Infusion-related reactions
Injection or infusion-related reactions with a start date and time within 24 hours of IMP administration.
Time frame: 24 hours post-IMP administration
Local reactions at the injection/infusion site
Local reactions at the injection or infusion site with a start date through Day 8 post-IMP administration.
Time frame: Day 1 through Day 8
Serious adverse events
SAEs are adverse events that fulfill any of the SAE criteria and are recorded with a start date from the date of informed consent form signature until the end of the study follow-up (Day 361)
Time frame: ICF date through Day 361
Medically attended adverse events (MAAEs)
MAAEs are adverse events leading to medically attended visits that were not routine visits, such as ER visit, or an otherwise unscheduled visit to or from medical personnel (medical doctor) for any reason.
Time frame: Day 1 through Day 361
Adverse events of special interest (AESIs)
AESIs as defined by Clinical Study Protocol.
Time frame: Day 1 through Day 361
Related adverse events
Related AEs are adverse events assessed as related to IMP by the Investigator.
Time frame: Day 1 through Day 361
Adverse events
AEs are defined as any unfavourable medical occurrence in a participant administered the IMP, regardless of the causal relationship to IMP.
Time frame: Day 1 through Day 91
Pharmacokinetics of AZD5148
PK will be characterized through AZD5148 serum concentrations over time in participants who receive AZD5148.
Time frame: Day 1 through Day 361
Anti-drug antibodies to AZD5148
Immunogenicity is evaluated through AZD5148 anti-drug antibody responses over time in serum from participants who receive AZD5148.
Time frame: Day 1 through Day 361
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Showing the first 100 of 117 sites across 14 countries. Choose a country and city above to see the rest.
Plan to share: Yes — Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.
Supporting information: Study protocol, Statistical analysis plan
Time frame: AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.
Access criteria: When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org. Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.
Data sharing details ↗ · vivli.org
No publications or documents are linked to this record.
Started Dec 2025 (actual). Primary completion is estimated for Apr 2027, 16 months after the start.
Of 23 phase 2 interventional studies under Clostridium Infections, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 19 and three quarters within 39. This study's planned 16 months is below that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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