Predictive Value of Modified Endothelial Activation and Stress Index (mEASIX) for Ruxolitinib Response in Graft-versus-Host Disease

Graft-versus-host disease (GVHD) continues to be a predominant cause of non-relapse morbidity and mortality following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Ruxolitinib is an established second-line treatment for steroid-refractory or steroid-dependent acute and chronic GVHD; however, predictive biomarkers for treatment response are lacking. The modified Endothelial Activation and Stress Index (mEASIX) is determined by measuring lactate dehydrogenase, C-reactive protein, and platelet count, and it indicates both endothelial damage and systemic inflammation. In this single-center retrospective study, we evaluated the predictive value of mEASIX for ruxolitinib response in 23 adult patients with GVHD. To assess the predictive capability of the mEASIX score, both receiver operating characteristic (ROC) analysis and logistic regression analysis were conducted. The median age was 37 years, and acute myeloid leukemia was the most common indication for transplantation (65.2%). Eleven patients had steroid-refractory/dependent acute GVHD, while 12 had steroid-refractory/dependent chronic GVHD. The overall response rate to ruxolitinib was 65.2%, with the lowest response observed in patients with bronchiolitis obliterans. Patients with ruxolitinib resistance had significantly higher mEASIX scores at treatment initiation compared to responders (37.09 vs. 5.38, p=0.008). Based on the ROC curve analysis optimal mEASIX cut-off value for predicting ruxolitinib resistance was 22.2 (sensitivity: 75%, specificity: 86.7%, AUC: 0.842, p