# Clostridium Difficile Vaccine 2-Dose Versus 3-Dose Study

> **NCT03918629** · PHASE3 · COMPLETED · sponsor: **Pfizer** · enrollment: 1994 (actual)

## Conditions studied

- Clostridium Difficile Associated Disease

## Interventions

- **BIOLOGICAL:** Clostridium difficile
- **BIOLOGICAL:** Placebo

## Key facts

- **NCT ID:** NCT03918629
- **Lead sponsor:** Pfizer
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2019-04-01
- **Primary completion:** 2020-12-22
- **Final completion:** 2020-12-22
- **Target enrollment:** 1994 (ACTUAL)
- **Last updated:** 2024-01-10


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT03918629

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT03918629, "Clostridium Difficile Vaccine 2-Dose Versus 3-Dose Study". Retrieved via AI Analytics 2026-06-09 from https://api.ai-analytics.org/clinical/NCT03918629. Licensed CC0.

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