A Clinical Trial to Evaluate the Safety, Efficacy, and Pharmacokinetics of MegaLT Injection for Treating Refractory Thrombocytopenia Following Radiotherapy, Chemotherapy, or Transplantation.

A study to evaluate the safety, efficacy, and pharmacokinetics of MegaLT in treating refractory thrombocytopenia following radiotherapy, chemotherapy, or transplantation.

Study Overview

• Status: Active, not recruiting
• Conditions: Refractory Thrombocytopenia
• Intervention / Treatment: Biological: MegaLT injection

Detailed Description

A single-center, open-label, dose-escalation study to assess the safety, efficacy, and pharmacokinetics of MegaLT for treating refractory thrombocytopenia following radiotherapy, chemotherapy, or transplantation.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Phase 1

Contacts and Locations

Study Locations

• China
  • Anhui
    • Hefei, Anhui, China, 230036
      • The First Affiliated Hospital of University of Science and Technology of China (Anhui Provincial Hospital)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age between 4 and 75 years (inclusive) at screening; gender is not restricted;
• Diagnosed with refractory thrombocytopenia following radiotherapy/chemotherapy or transplantation;
• Adequate organ function：Alanine aminotransferase (ALT) or Aspartate aminotransferase (AST) < 2.5*upper limit of normal (ULN); Serum creatinine < 1.5* ULN; Total bilirubin level < 1.5* ULN; Coagulation function: International Normalized Ratio (INR) ≤ 1.5* ULN, Activated Partial Thromboplastin Time (APTT) ≤ 1.5*ULN; Hemoglobin ≥ 60 g/L, or hemoglobin maintained at this level after transfusion; Absolute neutrophil count (ANC) ≥ 1.0×10^9/L;
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2;
• Voluntarily participating in the clinical trial, with full understanding of the trial details and having signed the informed consent form.

Exclusion Criteria:

• Patients with any malignant tumor relapse;
• Pregnant or breastfeeding women;
• Life expectancy less than 3 months;
• Severe infections or severe concurrent conditions such as heart, liver, lung, kidney, neurological, or metabolic diseases;
• History of severe thrombotic events or known thrombotic risk factors. Exceptions: Participants for whom the potential benefits of the study, as determined by the investigator, outweigh the potential risks of thromboembolic events;
• Uncontrolled infectious or other serious diseases, including but not limited to infections (e.g., HIV positive), congestive heart failure, unstable angina, arrhythmias, psychiatric disorders, or conditions that limit the ability to meet study requirements or pose unpredictable risks as judged by the primary physician;
• Active hepatitis B or C infection;
• Refractory thrombocytopenia post-transplant with Grade III-IV acute graft-versus-host disease (GVHD) [according to NIH standards] or severe chronic GVHD (NIH 2014 standards);
• History of organ transplantation or planned organ transplantation (excluding hematopoietic stem cell transplantation);
• Participation in another clinical study within 30 days prior to the baseline visit, involving any investigational drug or device; observational studies are allowed;
• Any other conditions deemed by the investigator to make the participant unsuitable for the clinical trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: MegaLT injection; Dosage Form: ex vivo three-dimensional induced umbilical cord blood mononuclear cells differentiated megakaryocyte injection (MegaLT injection). Administration Route: Intravenous Infusion Regimen: Single or Multiple Infusions

Biological: MegaLT injection; Three dose groups were set: 1×10^6/kg, 5×10^6/kg, and 1×10^7/kg. The dose escalation was carried out in ascending order using a "3+3" design. To ensure participant safety, enrollment followed a "1+2" rule. Specifically, the first participant in each dose group received the cell infusion and was observed for 14 days. If no dose-limiting toxicity (DLT) was observed, the remaining two participants could then be enrolled and receive cell therapy at the same dose level.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse Event(AE)	Number of treatment-related adverse events as assessed by CTCAE v4.0	From the date of initial infusion to 1 year after initial infusion
Incidence of bleeding events	The incidence of bleeding events after initial infusion	From the date of initial infusion to 1 year after initial infusion
The cumulative incidence and grade of graft-versus-host disease (GVHD) including acute and chronic GVHD	The occurrence incidence and grade of GVHD after transplantation	From the date of initial infusion to 1 year after initial infusion
The probability of GVHD-free, relapse-free survival(GRFS)	The composite endpoint of GRFS was defined as the first events occurring after transplantation among Grade III to IV aGVHD, moderate to severe cGVHD, relapse, or death for any reason.	From the date of initial infusion to 1 year after initial infusion
Overall response rate (ORR)	Percentage of participants achieved Complete response(CR) or Partial response(PR)	4 weeks after initial infusion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall response rate (ORR)	Percentage of participants achieved Complete Response(CR) or Partial Response(PR)	1, 2 and 8 weeks after initial infusion
Complete remission (CR) rate	CR was defined as a platelet count ≥ 50×10^9/L without platelet transfusions for 7 consecutive days	1, 2, 4 and 8 weeks after initial infusion
partial response rate (PR)	PR was defined as a platelet count < 50×10^9/L but above the baseline level at enrollment, with a sustained increase for 7 consecutive days without platelet transfusions	1, 2, 4 and 8 weeks after initial infusion
Changes in platelet counts	Changes in platelet counts before treatment and at 1, 2, 4, and 8 weeks after treatment	before treatment and at 1, 2, 4, and 8 weeks after treatment
Median time of platelet count ≥ 50×10^9/L	Platelet count ≥50×10^9/L for 3 consecutive days without platelet transfusions for 7 consecutive days	1 year after initial infusion
Median time of platelet count ≥ 100×10^9/L	Platelet count ≥50×10^9/L for 3 consecutive days without platelet transfusions for 7 consecutive days	1 year after initial infusion
Total platelet transfusion during 4 weeks of treatment	Total platelet transfusion during 4 weeks of treatment	4 weeks after initial infusion
neutrophil reconstitution	Neutrophil engraftment time was defined as the first of three consecutive days during which the neutrophil count was at least 0.5×10^9/L	1 year after initial infusion
Megakaryocyte levels in bone marrow smears	Megakaryocyte levels in bone marrow smears	before treatment and 2 and 4 weeks after treatment
erythroid reconstitution	Red blood count (RBC) engraftment time was defined as the first day of achieving a reticulocyte count greater than 1% for 3 consecutive days.	1 year after initial infusion

Collaborators and Investigators

• Sponsor: Anhui Provincial Hospital
• Investigators: Principal Investigator: Xiaoyu Zhu, Ph.D, The First Affiliated Hospital of University of Science and Technology of China

Study record dates

Study Major Dates

• Study Start (Actual): December 4, 2024
• Primary Completion (Actual): June 19, 2025
• Study Completion (Estimated): May 22, 2026

Study Registration Dates

• First Submitted: July 30, 2024
• First Submitted That Met QC Criteria: July 30, 2024
• First Posted (Actual): August 2, 2024

Study Record Updates

• Last Update Posted (Actual): April 14, 2026
• Last Update Submitted That Met QC Criteria: April 12, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Refractory thrombocytopenia; Megakaryocyte
• Additional Relevant MeSH Terms: Cytopenia; Hematologic Diseases; Blood Platelet Disorders; Hemic and Lymphatic Diseases; Thrombocytopenia
• Other Study ID Numbers: MegaLT-2024

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No