Efficacy and Safety of MegaLT Injection for Platelet Recovery After Umbilical Cord Blood Transplantation

This is a single-arm, early safety and feasibility exploratory study to evaluate the efficacy and safety of MegaLT Injection in promoting platelet recovery after umbilical cord blood transplantation. Adults with malignant hematologic diseases who undergo umbilical cord blood transplantation will receive a single intravenous infusion of MegaLT Injection on day 14 after transplantation. Two dose levels will be evaluated sequentially, and platelet recovery, platelet transfusion requirements, and safety outcomes will be assessed.

Inclusion Criteria: * Age ≥18 years, male or female. * Patients with a definite diagnosis of hematologic malignancy who are undergoing umbilical cord blood transplantation. * Patients at day 14 after umbilical cord blood transplantation. * ECOG performance status ≤2. * Patients who voluntarily agree to participate in this clinical trial, fully understand the study content, and sign the informed consent form. Exclusion Criteria: * Patients with relapse of any malignant tumor. * Pregnant or lactating women. * Patients with severe infection or severe cardiac, hepatic, pulmonary, renal, neurologic, or metabolic disease. * Patients with a history of severe thrombotic events or known risk factors for thrombosis. Exception: participants for whom the investigator determines that the potential benefit of study participation outweighs the potential risk of thromboembolic events. * Patients with uncontrolled infectious disease or other serious diseases, including but not limited to infection such as HIV positivity, congestive heart failure, unstable angina, cardiac arrhythmia, psychosis, social circumstances that would limit compliance with study requirements, or any condition that the treating physician considers may pose unpredictable risks. * Patients with active hepatitis B or hepatitis C. * Patients who have previously received organ transplantation or are planning to receive organ transplantation, except for hematopoietic stem cell transplantation. * Patients who participated in another clinical study and used any investigational drug or device within 30 days before the baseline visit. Participation in observational studies is allowed. * Patients considered by the investigator to be unsuitable for participation in this clinical trial for any other reason.