Efficacy of Thymosin α1 for Sepsis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Bin Gu^1,2Yu Zhou^1,2Yao Nie^1,2Luhao Wang^1,2Liqun Liang^1,2Zihuai Liao^1,2Jingyi Wen^1,2Xiangdong Guan^1,2Minying Chen^1,2*Wu Jianfeng^1,2*Fei Pei^1,2*

• ¹Department of Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
• ²Guangdong Clinical Research Center for Critical Care Medicine, Guangzhou, China

Background Despite advances in understanding sepsis pathophysiology and extensive research, few treatments effectively target its underlying immune dysfunction. Thymosin α1 (Tα1) shows promise as an immunomodulator, but its impact on sepsis remains unclear. Methods A search strategy was designed to include any prospective clinical studies using Tα1 for assessing 28-day mortality in patients with sepsis, excluding combination therapy studies. We conducted trial sequential analysis (TSA) to assess the robustness of meta-analyses findings. Heterogeneity of treatment effects (HTE) was conducted based on individual data from two multicenter randomized clinical trials (RCTs), with result credibility assessed through the instrument to assess the credibility of effect modification analyses (ICEMAN). Results Out of 3003 identified studies, 11 RCTs met the inclusion criteria (967 patients in Tα1 group and 960 patients in control group). The comprehensive meta-analysis demonstrated a significant reduction in 28-day mortality associated with Tα1 administration (OR 0.73, 95%CI: 0.59-0.90, P=0.003). Nonetheless, analyses of high-quality (OR 0.82, 95%CI: 0.65-1.03, P=0.09) and multi-center (OR 0.86, 95%CI: 0.68-1.08, P=0.20) subgroups did not reveal a mortality benefit. The HTE analysis of multiple subgroups in two large RCTs (representing 75% of the total patients) showed heterogeneity. Potential benefits were noted in subgroups of cancer (moderate credibility), diabetes (low credibility), and coronary heart disease (low credibility). Furthermore, the trial sequential analysis (TSA) suggests that the current sample size is inadequate. Conclusion Tα1 has the potential to decrease 28-day mortality rates in patients with sepsis; however, it is crucial to recognize that its efficacy differs among various subgroups. These observations underscore the significance of personalized immunotherapy strategies in forthcoming clinical trials.