This multicenter randomized controlled trial evaluates the efficacy of thymosin alpha 1 (Tα1) supplementation in preventing organ dysfunction following acute type A aortic dissection (ATAAD) repair. Over 330 patients will be equally assigned to receive either Tα1 plus standard care or placebo with standard management. The primary endpoint involves calculating the difference in mean postoperative Sequential Organ Failure Assessment (SOFA) scores between groups, measured daily from postoperative days 7. By targeting post-operative immune system imbalance, this study aims to establish a novel therapeutic approach for reducing systemic inflammatory response syndrome (SIRS)-mediated organ injury and improving long-term outcomes in this high-risk population. Results will be disseminated through peer-reviewed publications and international conferences.: ClinicalTrials.gov Registry (NCT05339529).