[Efficacy and Safety of Different GVHD Prophylaxis Regimens for Unrelated Donor Hematopoietic Stem Cell Transplantation: A Real-World Long-Term Retrospective Study].

OBJECTIVE

To analyze the efficacy and safety of anti-thymocyte globulin (ATG), anti-CD25 monoclonal antibody (CD25 mAb), and maraviroc (MVC) as graft-versus-host disease (GVHD) prophylaxis regimens in patients with high-risk acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes (MDS) undergoing unrelated donor hematopoietic stem cell transplantation (unrelated-HSCT).

METHODS

The clinical characteristics of 193 high-risk AML/MDS patients who underwent unrelated-HSCT at the Fifth Medical Center of Chinese PLA General Hospital from January 2011 to December 2018 were retrospectively analyzed. Patients were divided into three groups based on the GVHD prophylaxis: ATG group (n=46), CD25 mAb group (n=126), and MVC group (n=21). The cumulative incidences of acute GVHD (aGVHD), chronic GVHD (cGVHD), relapse and non-relapse mortality (NRM), as well as disease-free survival (DFS), overall survival (OS) were analyzed.

RESULTS

The ATG, CD25 mAb and MVC groups showed no statistically significant differences in hematopoietic reconstitution (P>0.05). The cumulative incidence of 100 d grade Ⅱ-Ⅳ aGVHD in CD25 mAb, ATG and MVC group was 42.1%, 24.0% and 19.0% respectively, with a statistically significant difference (P=0.020). Multivariate Cox regression analysis showed that ATG (HR=0.47，P=0.028) and MVC (HR=0.36，P=0.045) were independent protective factors for reducing the incidence of grade Ⅱ-Ⅳ aGVHD. There were no significant differences in 100d grade Ⅲ-Ⅳ aGVHD (P=0.239), 5-year cGVHD (P=0.123), moderate-severe cGVHD (P=0.100), DFS (P=0.130), OS (P=0.271), and NRM (P=0.949). The 5-year cumulative incidence of relapse in the ATG, CD25 mAb and MVC group was 13.3% 35.9% and 38.1%, respectively, with a statistically significant difference (P=0.011). Multivariate Cox regression analysis showed that ATG was an independent protective factor for reducing recurrence rate (HR=0.34，P=0.016). The 5-year GRFS in the ATG, CD25 mAb and MVC group was 38.0%, 21.0% and 9.5%, respectively, with a statistically significant difference (P=0.034). Multivariate Cox regression analysis showed that ATG was an independent protective factor for improving GRFS (HR=0.54，P=0.008).

CONCLUSION

This study concludes that among high-risk AML/MDS patients receiving unrelated-HSCT, an ATG-based regimen for GVHD prophylaxis can effectively reduce the incidence and recurrence rate of acute GVHD, improve GRFS, and should be considered as the preferred strategy.