Hepato<u>p</u>ancreaticobiliary <u>R</u>esection Arginine <u>I</u>mmuno<u>m</u>odulation (PRIMe) trial: protocol for a randomised phase II trial of the impact of perioperative immunomodulation on immune function following resection for hepatopancreaticobiliary malignancy.

Abstract

Surgical stress results in immune dysfunction, predisposing patients to infections in the postoperative period and potentially increasing the risk of cancer recurrence. Perioperative immunonutrition with arginine-enhanced diets has been found to potentially improve short-term and cancer outcomes. This study seeks to measure the impact of perioperative immunomodulation on biomarkers of the immune response and perioperative outcomes following hepatopancreaticobiliary surgery. This is a 1:1:1 randomised, controlled and blinded superiority trial of 45 patients. Baseline and perioperative variables were collected to evaluate immune function, clinical outcomes and feasibility outcomes. The primary outcome is a reduction in natural killer cell killing as measured on postoperative day 1 compared with baseline between the control and experimental cohorts. This trial has been approved by the research ethics boards at participating sites and Health Canada (parent control number: 223646). Results will be distributed widely through local and international meetings, presentation, publication and ClinicalTrials.gov (identifier: NCT04549662). Any modifications to the protocol will be communicated via publications and ClinicalTrials.gov. ClinicalTrials.gov identifier: NCT04549662.