Hetrombopag for enhancement of platelet engraftment after allogeneic hematopoietic stem cell transplantation: A single-center experience.

Abstract

Background: Delayed platelet engraftment is a significant complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Objectives: This retrospective study evaluates the efficacy and safety of hetrombopag, an oral thrombopoietin receptor agonist, in promoting platelet engraftment post-allo-HSCT.

Design: Retrospective observational cohort study.

Methods: A cohort of 133 patients was analyzed, including 68 treated with hetrombopag post-transplant and 65 controls. Cumulative incidence function evaluated platelet engraftment, with propensity score matching and competing risk analysis to strengthen robustness. Factors associated with platelet engraftment were examined using multivariate Cox models with time-dependent coding of hetrombopag exposure.

Results: Hetrombopag significantly reduced the time to overall response (OR: 15.0 days vs. 20.0 days; p = 0.009) and complete response (CR: 17.5 days vs. 34.0 days; p < 0.001). The cumulative incidence of CR was higher in the hetrombopag group (92.78% vs. 86.58%; p = 0.001), with a significantly shorter median time to CR (19 days vs. 38 days) defined by the cumulative incidence function. Multivariate Cox regression identified hetrombopag as a protective factor for platelet recovery (HR: 2.04; p = 0.004). Competing risk and PSM analyses confirmed hetrombopag's role in faster platelet engraftment. The treatment was well-tolerated, with manageable mild liver enzyme elevations and hypomagnesemia but no grade 3/4 adverse events.

Conclusion: Hetrombopag significantly accelerates platelet engraftment and has a favorable safety profile, suggesting its potential as a therapeutic adjunct in managing thrombocytopenia post-allo-HSCT. This study complements and validates findings from prior prospective studies, providing external confirmation in a real-world cohort.