BACKGROUND: In this statistical analysis plan, we aim to provide details of the pre-defined statistical analyses of the Stress Ulcer Prophylaxis in the Intensive Care Unit (SUP-ICU) trial. The aim of the SUP-ICU trial is to assess benefits and harms of stress ulcer prophylaxis with a proton pump inhibitor in adult patients in the intensive care unit (ICU).

METHODS: The SUP-ICU trial is an investigator-initiated, international, multicentre, randomised, blinded, parallel-group trial of intravenously pantoprazole 40 mg once daily vs. placebo in 3350 acutely ill adult ICU patients at risk of gastrointestinal bleeding. The primary outcome measure is 90-day mortality. Secondary outcomes include the proportion of patients with clinically important gastrointestinal bleeding, pneumonia, Clostridium difficile infection or myocardial ischaemia, days alive without life support, serious adverse reactions, 1-year mortality, and a health economic analysis. Two formal interim analyses will be performed. The statistical analyses will be conducted according to the outlined pre-defined statistical analysis plan. The primary analysis will be a logistic regression analysis adjusted for stratification variables comparing the two intervention groups in the intention-to-treat population. In a secondary analysis, we will additionally adjust the primary outcome for potential random differences in baseline characteristics. The conclusion will be based on the intention-to-treat population.

CONCLUSION: Stress ulcer prophylaxis is standard of care in ICUs worldwide, but has never been tested in large high-quality randomised placebo-controlled trials. The SUP-ICU trial will provide important high-quality data on the balance between the benefits and harms of stress ulcer prophylaxis in adult critically ill patients.