Overview
This prospective, multicenter, randomized controlled Phase II study is designed to evaluate the efficacy and safety of romiplostim for platelet engraftment after haploidentical or HLA-matched unrelated donor allogeneic hematopoietic stem cell transplantation. Approximately 120 patients aged ≥18 years will be randomized equally to the romiplostim group or the best supportive care group. Romiplostim will be administered subcutaneously at 1 μg/kg once weekly, starting on day +3 after transplantation. The primary outcomes are platelet engraftment rates at days +30 after transplantation.
Description
This investigator-initiated, prospective, multicenter, randomized controlled Phase II study is designed to evaluate the efficacy and safety of romiplostim for platelet engraftment after haploidentical or HLA-matched unrelated donor allogeneic hematopoietic stem cell transplantation (allo-HSCT).
Approximately 120 patients with hematologic diseases undergoing allo-HSCT will be enrolled and randomized in a 1:1 ratio to the romiplostim group or the best supportive care group. Eligible participants must meet protocol-defined inclusion criteria, including age ≥18 years, an ECOG performance status of 0-3, an expected survival of ≥4 months, and adequate hepatic and renal function. Patients with uncontrolled infections or other protocol-defined exclusion criteria will not be eligible. Written informed consent will be obtained from all participants before enrollment.
Participants assigned to the romiplostim group will receive romiplostim at a dose of 1 μg/kg by subcutaneous injection once weekly, starting on day +3 after transplantation. Participants in both groups will receive transfusion support and other supportive treatments according to clinical needs and the judgment of treating physicians.
The primary efficacy outcomes are platelet engraftment rates at days +30 after transplantation. Platelet engraftment is defined as a platelet count greater than 20 × 10⁹/L for seven consecutive days without platelet transfusion support.
Secondary outcomes include time to platelet engraftment, time to neutrophil engraftment, disease relapse rate, incidence of graft-versus-host disease (GVHD), non-relapse mortality (NRM), overall survival (OS), and the incidence of grade ≥3 adverse events and laboratory abnormalities.
Safety assessments will include the incidence of adverse events, treatment-related adverse events, and adverse events leading to death, treatment discontinuation, or premature withdrawal from the study.
Blood counts and other laboratory assessments will be monitored according to the protocol-defined schedule. The primary data analysis will be performed after the last enrolled participant completes the treatment period and 3 months of follow-up. All participants will continue long-term follow-up to evaluate survival outcomes and other long-term clinical outcomes.
Eligibility
Inclusion Criteria:
- Age ≥18 years, regardless of sex.
- Undergoing haploidentical or fully HLA-matched unrelated donor allogeneic hematopoietic stem cell transplantation for a hematologic disease.
- No severe allergic predisposition.
- No uncontrolled infection or severe psychological disorder.
- Hepatic function: alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5 times the upper limit of normal (ULN), and bilirubin ≤2 times ULN.
- Renal function: creatinine ≤ULN.
- Eastern Cooperative Oncology Group (ECOG) performance status of 0-3 and an anticipated life expectancy of ≥4 months.
- Voluntary participation, with written informed consent provided by the participant or their legally authorized representative after fully understanding the study, and willingness and ability to comply with and complete all study procedures.
Exclusion Criteria:
- Pregnancy or breastfeeding.
- Known hypersensitivity to the study drug or any contraindication to its use.
- Severe hepatic impairment, defined as ALT or AST ≥5 times ULN.
- Smoking or chronic alcohol abuse that may interfere with the evaluation of study results.
- Psychiatric illness or another condition that prevents informed consent from being obtained or precludes cooperation with required treatment and examination procedures.
- Major organ surgery within the preceding six weeks.
- Any other significant medical condition, laboratory abnormality, or psychiatric disorder that, in the investigator's judgment, makes the individual unsuitable for study participation.
