Herombopag Versus rhTPO in Stem Cell Transplantation: A Comparative Study of Efficacy, Safety, and Cost-Effectiveness.

Abstract

Background: Thrombocytopenia remains a significant clinical challenge following peripheral blood stem cell transplantation (PBSCT), with delayed platelet engraftment (DPE) associated with increased morbidity and mortality. While current strategies including platelet transfusions and recombinant human thrombopoietin (rhTPO) are widely used, their clinical utility is constrained by suboptimal efficacy, high costs, and administration challenges. Herombopag, a novel second-generation thrombopoietin receptor agonist (TPO-RA), presents potential advantages due to its oral bioavailability and unique mechanism of action. This retrospective study aimed to comprehensively compare herombopag with rhTPO in terms of hematopoietic recovery, safety profile, and economic impact in both autologous (auto-) and allogeneic (allo-) PBSCT settings.

Methods: We conducted a retrospective cohort analysis of 106 consecutive PBSCT patients (56 auto-PBSCT, 50 allo-PBSCT) treated between January 2022 and October 2024. Patients were stratified into two intervention groups: oral herombopag (5 mg/day) versus subcutaneous rhTPO (15,000 U/day), initiated when platelet counts dropped below 30 × 10⁹/L. Primary endpoints included time to neutrophil and platelet engraftment, while secondary endpoints encompassed bleeding events, transfusion requirements, infectious complications (CMV, EBV, BKV), GVHD incidence, drug-related toxicities, and overall treatment costs. Rigorous statistical analyses were performed using SPSS v26.0, employing appropriate parametric and nonparametric tests with statistical significance set at P < .05.

Results: Engraftment Kinetics: In auto-PBSCT, comparable results were observed between groups for both neutrophil (herombopag: 12.25 ± 1.30 days versus rhTPO: 12.43 ± 1.35 days; P = .615) and platelet engraftment (13.32 ± 1.31 versus 13.61 ± 1.23 days; P = .403). Allo-PBSCT patients receiving herombopag demonstrated significantly faster hematopoietic recovery: neutrophil engraftment (12.76 ± 1.81 versus 13.80 ± 1.71 days; P = .042) and platelet engraftment (15.76 ± 2.59 versus 17.72 ± 2.81 days; P = .013).

Clinical outcomes: Bleeding events were markedly reduced with herombopag in both auto-PBSCT (7.1% versus 42.9%; P = .005) and allo-PBSCT (8.0% versus 40.0%; P = .020) cohorts. Platelet transfusion requirements were significantly lower in herombopag-treated patients (auto-PBSCT: 1.11 ± 1.10 versus 2.04 ± 1.07 units, P = .002; allo-PBSCT: 1.64 ± 1.85 versus 3.56 ± 1.96 units, P = .001).

Safety profile: Comparable rates of viral reactivation (CMV, EBV, BKV), GVHD, and manageable liver function abnormalities were observed between groups. No thrombotic complications or significant survival differences were noted at 2-year follow-up (OS/PFS, P>0.05).

Economic evaluation: Herombopag demonstrated substantial cost savings, reducing medication expenses by 87% in auto-PBSCT (median 138.13 versus 1041.04 USD; P = .000) and 84% in allo-PBSCT (211.25 versus 1315 USD; P = .000).

Discussion: Our findings establish herombopag as an effective and cost-saving alternative to rhTPO, particularly in the allo-PBSCT setting where it demonstrated superior engraftment kinetics. The significant reduction in bleeding complications and transfusion requirements, coupled with its convenient oral administration, positions herombopag as an attractive therapeutic option. While the safety profiles were comparable, herombopag's economic advantages and potential immunomodulatory effects warrant further investigation. Study limitations include its retrospective nature and moderate sample size, highlighting the need for prospective randomized controlled trials to validate these observations.

Conclusion: This study provides robust evidence that herombopag is a safe, effective, and economically favorable therapy for post-PBSCT thrombocytopenia. Its demonstrated benefits in accelerating platelet recovery, reducing hemorrhagic complications, and lowering healthcare costs suggest it should be considered as a preferred therapeutic option, especially for allo-PBSCT recipients. These findings have important implications for optimizing supportive care in hematopoietic stem cell transplantation.