MedPath

Observational Study: Hetrombopag for Platelet Recovery in Haploidentical HSCT

Conditions
Thalassemia in Children
Interventions
Registration Number
NCT07003269
Lead Sponsor
Haikou Affiliated Hospital of Central South University Xiangya School of Medicine
Brief Summary

The objective of this observational study is to investigate the long-term effects of Hetrombopag in promoting platelet engraftment during haploidentical hematopoietic stem cell transplantation (HSCT) in children with thalassemia, with a specific focus on a 28-day time window post-transplantation. The core question to be addressed is: Is Hetrombopag safe and effective for platelet engraftment in children with thalassemia undergoing haploidentical HSCT within a 28-day post-transplant period? Subjects who received Hetrombopag as part of routine care for haploidentical HSCT in children with thalassemia will be required to complete a 28-day online survey on platelet engraftment outcomes.

Detailed Description

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a critical and often the sole curative modality for diverse hematological malignancies and disorders. Post-transplant thrombocytopenia (platelet count \<20×10⁹/L) significantly compromises long-term patient survival, with an incidence of 5-20% in allo-HSCT recipients, thereby escalating treatment morbidity and costs. Current research on platelet engraftment promotion in pediatric thalassemia patients undergoing allo-HSCT is limited. Repeated platelet transfusions are associated with substantial complications, including transfusion reactions, platelet alloimmunization, and transfusion-transmitted viral infections. Eltrombopag, a thrombopoietin receptor agonist (TPO-RA), carries a black-box warning for hepatotoxicity, with a real-world incidence of 11.8%. Transplant recipients frequently experience diarrhea, which impairs the absorption of oral thrombopoietic agents, while daily subcutaneous injections exacerbate pediatric patient discomfort and reduce treatment adherence. In contrast, long-acting TPO-RAs administered once post-transplant have demonstrated favorable tolerability and promising efficacy in thalassemia transplant pediatric populations. To date, clinical data on Hetrombopag use for platelet recovery in haploidentical HSCT for pediatric thalassemia are lacking. Therefore, this observational study aims to evaluate the efficacy and safety of Hetrombopag in facilitating platelet engraftment during haploidentical HSCT in children with thalassemia.

Recruitment & Eligibility

Status
ENROLLING_BY_INVITATION
Sex
All
Target Recruitment
30
Inclusion Criteria
  • Diagnosed with severe thalassemia via thalassemia gene testing, transfusion history, and complete blood count (CBC).
  • Pediatric patients aged 2-17 years.
  • Consented to haploidentical transplantation and evaluated by the transplant team as having no transplant contraindications.
Exclusion Criteria
  • Presence of a fully matched donor with refusal of haploidentical transplantation.
  • Donor or recipient with transaminase levels >2× the upper limit of normal (ULN).
  • Positive hepatitis B DNA test result.
  • Active infection at the time of enrollment.
  • Donor-specific antibodies (DSA) >5,000 and unable to decrease below 3,000 after antibody therapy.
  • Presence of transplant contraindications as assessed by the transplant team.

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Experimental groupHetrombopagIn allogeneic hematopoietic stem cell transplantation, hetrombopag is initiated at 3 µg/kg subcutaneously on day +6 post-transplant. The dose is increased by 2 µg/kg weekly up to a maximum of 10 µg/kg. Treatment is discontinued when platelet counts rise to 100×10⁹/L. If platelet counts remain ≤20×10⁹/L on day +20, hetrombopag is combined with eltrombopag 25 mg orally once daily. Fresh apheresis platelet suspensions (1 therapeutic dose, containing \>2.5×10¹¹ platelets) are administered when platelet counts are ≤20×10⁹/L or when counts are between 21-50×10⁹/L with active bleeding. If engraftment has not occurred by day +28 post-transplant, re-transplantation is required, and hetrombopag is considered ineffective.
Primary Outcome Measures
NameTimeMethod
Platelet recovery timeFrom enrollment to 28 days after transplantation

The time at nodes such as platelet \>20×10\^9/L, 50×10\^9/L and 100×10\^9/L

Platelet transfusion volumeFrom enrollment to 28 days after transplantation

Required dosage of platelet suspension

Secondary Outcome Measures
NameTimeMethod
Transplant-related mortality rateFrom enrollment to 28 days after transplantation
Major transplant-related complicationsFrom enrollment to 28 days after transplantation
Cause of deathFrom enrollment to 28 days after transplantation
The rate of adverse drug reactionsFrom enrollment to 28 days after transplantation

The rate of adverse drug reactions occurring during the follow-up period

Bleeding incidence rateFrom enrollment to 28 days after transplantation

The incidence rate of bleeding during the follow-up period

Thrombosis incidence rateFrom enrollment to 28 days after transplantation

The incidence rate of thrombosis during the follow-up period

Survival rateFrom enrollment to 28 days after transplantation
Relapse-free survival rateFrom enrollment to 28 days after transplantation

Trial Locations

Locations (1)

Haikou Affiliated Hospital of Central South University Xiangya School of Medicine

🇨🇳

Haikou, Hainan, China

© Copyright 2025. All Rights Reserved by MedPath