Single-Dose vs. Divided-Dose G-CSF for Stem Cell Mobilization in Healthy Allogeneic Donors

Randomized Controlled Trial Comparing Single-dose and Divided-dose G-CSF for Peripheral Blood Stem Cell Mobilization in Healthy Donors for Allogeneic Hematopoietic Stem Cell Transplantation.

National and international guidelines/consensus recommend G-CSF (granulocyte colony-stimulating factor) at 10 μg/kg/day as a single daily dose or divided into two daily doses for mobilization in healthy donors for allogeneic hematopoietic stem cell transplantation. However, there is no consensus or standard regarding single versus divided dosing, and high-quality evidence is lacking. Existing randomized controlled trials have small sample sizes and inconsistent conclusions, and none have focused on Asian population characteristics (e.g., body weight and drug metabolism differences). This study aims to provide level I evidence to optimize donor experience and define the optimal administration strategy.

Inclusion criteria: Healthy allogeneic stem cell donors aged 18-60 years, meeting institutional standard donor screening criteria (HLA matching, normal blood counts, normal liver and kidney function, negative infection screening), and providing written informed consent.

Primary endpoint: The rate of achieving a first apheresis yield of ≥ 4 × 10⁶ CD34⁺ cells/kg (donor body weight) after 5 days of G-CSF mobilization.

Secondary endpoints: The rate of achieving ≥ 2 × 10⁶ CD34⁺ cells/kg with at most one apheresis; time to myeloid, platelet, and erythroid engraftment in recipients; the proportion and composition of immune cells (CD34⁺, CD3⁺, CD19⁺, CD56⁺, etc.) in the apheresis product; donor adverse events; donor-reported outcomes; and the difference in CD34⁺ stem cell yields between single-dose and divided-dose mobilization.

Intervention: G-CSF will be administered at a total dose of 10 μg/kg/day, either as a single daily injection or divided into two equal daily injections.

This study is designed to investigate whether single-dose or divided-dose G-CSF administration is superior for mobilizing healthy donors in allogeneic hematopoietic stem cell transplantation.

Study Overview

• Status: Not yet recruiting
• Conditions: Healthy Hematopoietic Stem Cell Donor; Healthy Allogeneic Hematopoietic Stem Cell Donor
• Intervention / Treatment: Drug: Divided-dose Granulocyte colony-stimulating factor (G-CSF); Drug: Single-dose Granulocyte colony-stimulating factor (G-CSF)

Detailed Description

National and international guidelines/consensus recommend G-CSF (granulocyte colony-stimulating factor) at 10 μg/kg/day as a single daily dose or divided into two daily doses for mobilization in healthy donors for allogeneic hematopoietic stem cell transplantation. However, there is no consensus or standard regarding single versus divided dosing, and high-quality evidence is lacking. Existing randomized controlled trials have small sample sizes and inconsistent conclusions, and none have focused on Asian population characteristics (e.g., body weight and drug metabolism differences). This study aims to provide level I evidence to optimize donor experience and define the optimal administration strategy.

Inclusion criteria: Healthy allogeneic stem cell donors aged 18-60 years, meeting institutional standard donor screening criteria (HLA matching, normal blood counts, normal liver and kidney function, negative infection screening), and providing written informed consent.

Primary endpoint: The rate of achieving a first apheresis yield of ≥ 4 × 10⁶ CD34⁺ cells/kg (donor body weight) after 5 days of G-CSF mobilization.

Secondary endpoints: The rate of achieving ≥ 2 × 10⁶ CD34⁺ cells/kg with at most one apheresis; time to myeloid, platelet, and erythroid engraftment in recipients; the proportion and composition of immune cells (CD34⁺, CD3⁺, CD19⁺, CD56⁺, etc.) in the apheresis product; donor adverse events; donor-reported outcomes; and the difference in CD34⁺ stem cell yields between single-dose and divided-dose mobilization.

Intervention: G-CSF will be administered at a total dose of 10 μg/kg/day, either as a single daily injection or divided into two equal daily injections.

Weight-based mobilization: G-CSF 10 μg/kg/day × 5 days, SC, once daily or in two divided doses (max 7 days). Apheresis begins on day 5; subsequent dosing and collections are guided by the CD34⁺ yield, not to exceed 7 days.

This study is designed to investigate whether single-dose or divided-dose G-CSF administration is superior for mobilizing healthy donors in allogeneic hematopoietic stem cell transplantation.

• Study Type: Interventional
• Enrollment (Estimated): 560
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: YIBO WU; Phone Number: +8657187233801; Email: wuyibo7@126.com

Study Locations

• China
  • Hunan
    • Changsha, Hunan, China
      • Xiangya Hospital of Central South University
      • Contact: Yajing Xu; Phone Number: +8657187233801; Email: xyyajingxu@csu.edu.cn
  • Zhejiang
    • Hangzhou, Zhejiang, China
      • The Second Affiliated Hospital of Zhejiang University School of Medicine
      • Contact: Yang XU; Phone Number: +8657187233801; Email: yxu@zju.edu.cn
    • Hangzhou, Zhejiang, China
      • Sir Run Run Shaw Hospital, Zhejiang University School of Medicine
      • Contact: Haowen Xiao; Phone Number: +8657187233801; Email: haowenxiaoxiao@zju.edu.cn
    • Hangzhou, Zhejiang, China
      • The First Affiliated Hospital, Zhejiang University School of Medicine.
      • Contact: YIBO WU; Phone Number: +8657187233801; Email: wuyibo7@126.com
    • Jinhua, Zhejiang, China
      • Jinhua Central Hospital
      • Contact: Lihong Ni; Phone Number: +8657187233801; Email: nilihongwy@163.com
    • Ningbo, Zhejiang, China
      • The Affiliated People's Hospital of Ningbo University
      • Contact: Ying Lu; Phone Number: +8657187233801; Email: rmluying@nbu.edu.cn
    • Ningbo, Zhejiang, China
      • The First Affiliated Hospital of Ningbo University
      • Contact: Lieguang Chen; Phone Number: +8657187233801; Email: fyychenlieguang@nbu.edu.cn
    • Wenzhou, Zhejiang, China
      • The First Affiliated Hospital of Wenzhou Medical University
      • Contact: Yi Chen; Phone Number: +8657187233801; Email: chenyi19527@163.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Age 18-65 years.
2. Provision of written informed consent.
3. White blood cell (WBC) count > 2.5 × 10⁹/L.
4. Absolute neutrophil count (ANC) > 1.5 × 10⁹/L and platelet count > 100 × 10⁹/L.
5. Deemed suitable as a donor by the investigator based on donor physical examination and HLA matching.
6. Body weight ≥ 40 kg for females and ≥ 45 kg for males.

Exclusion Criteria:

1. Currently having any disease or condition that, in the judgment of the investigator, would make the donor unsuitable for participation in this study, such as severe neurological, hepatic, renal, endocrine, cardiovascular, hematologic, gastrointestinal, respiratory, or metabolic diseases; malignancies; myeloproliferative disorders; or psychiatric illnesses.
2. Currently having an active infection requiring systemic therapy.
3. Allergy to the study drug.
4. Presence of a malignant tumor.
5. Untreated HBV infection with HBV-DNA above the lower limit of detection.
6. HIV infection.
7. Addition of any new medication within 2 weeks prior to entry into this study.
8. Female donors who are pregnant or breastfeeding.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Divided-dose Arm; G-CSF 10 μg/kg per day divided into two equal subcutaneous doses daily for 5 days (up to 7 days if needed).	Drug: Divided-dose Granulocyte colony-stimulating factor (G-CSF); G-CSF 10 μg/kg per day divided into two equal subcutaneous doses daily for 5 days (up to 7 days if needed)
Active Comparator: Single-dose Arm; G-CSF 10 μg/kg administered subcutaneously once daily for 5 days (up to 7 days if needed based on CD34⁺ yield).	Drug: Single-dose Granulocyte colony-stimulating factor (G-CSF); G-CSF 10 μg/kg administered subcutaneously once daily for 5 days (up to 7 days if needed based on CD34⁺ yield).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of donors achieving a first apheresis yield of ≥ 4 × 10⁶ CD34⁺ cells/kg (donor weight).	Proportion of donors achieving a first apheresis yield of ≥ 4 × 10⁶ CD34⁺ cells/kg (donor weight).	From enrollment to the end of stem cell collection (8 weeks)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of donors achieving a yield of ≥ 2 × 10⁶ CD34⁺ cells/kg (donor weight) with no more than one apheresis.	Proportion of donors achieving a yield of ≥ 2 × 10⁶ CD34⁺ cells/kg (donor weight) with no more than one apheresis.	From enrollment to the end of stem cell collection (8 weeks)
Cumulative incidence rates of neutrophil engraftment in allogeneic stem cell transplant recipients.	Defined as time from stem cell infusion to the first of three consecutive days with ANC ≥ 0.5 × 10⁹/L.	28 days after transplantation
Cumulative incidence rates of platelet engraftment in allogeneic stem cell transplant recipients.	Proportion of recipients achieving platelet count ≥ 20 × 10⁹/L with no platelet transfusion for at least 7 consecutive days, by Day +28 post-transplant.	28 days after transplantation
Cumulative incidence rates of erythroid engraftment in allogeneic stem cell transplant recipients.	Proportion of recipients achieving hemoglobin ≥ 60 g/L without red blood cell transfusion for at least 7 consecutive days, by Day +28 post-transplant.	28 days after transplantation
The proportion and composition of immune cells (including CD34⁺, CD3⁺, CD19⁺, CD56⁺, etc.) in the apheresis product	The proportion and composition of immune cells (including CD34⁺, CD3⁺, CD19⁺, CD56⁺, etc.) in the apheresis product	From enrollment to the end of stem cell collection (8 weeks)
Donor adverse events and recipient-reported outcomes	Donor adverse events and recipient-reported outcomes	From enrollment to the end of stem cell collection (8 weeks)
Comparison of peripheral blood CD34⁺ cell counts (cells/μL) on Days 1, 2, 3, 4, and 5 between healthy donors mobilized with single-dose versus divided-dose G-CSF	Comparison of peripheral blood CD34⁺ cell counts (cells/μL) on Days 1, 2, 3, 4, and 5 between healthy donors mobilized with single-dose versus divided-dose G-CSF	From enrollment to the end of stem cell collection (8 weeks)
Comparison of the rate of engraftment failure in recipients between the two groups	Comparison of the rate of engraftment failure in recipients between the two groups	From enrollment to the end of stem cell collection (8 weeks)
Comparison of overall survival (OS) rates at 2 years in recipients between the two groups;	Comparison of overall survival (OS) rates at 2 years in recipients between the two groups;	2 years post transplantation
Comparison of overall survival (OS) rates at 5 years in recipients between the two groups;	Comparison of overall survival (OS) rates at 5 years in recipients between the two groups;	5 years post transplantation
Comparison of CD34⁺ stem cell yield in the apheresis product between the two groups	Comparison of CD34⁺ stem cell yield in the apheresis product between the two groups	From enrollment to the end of stem cell collection (8 weeks)

Collaborators and Investigators

• Sponsor: First Affiliated Hospital of Zhejiang University
• Collaborators: Xiangya Hospital of Central South University; Second Affiliated Hospital, School of Medicine, Zhejiang University; Sir Run Run Shaw Hospital; First Affiliated Hospital of Wenzhou Medical University; Jinhua Central Hospital; The Affiliated People's Hospital of Ningbo University; First Affiliated Hospital of Ningbo University
• Investigators: Principal Investigator: YI LUO, Zhejiang University

Study record dates

Study Major Dates

• Study Start (Estimated): July 10, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): July 10, 2029

Study Registration Dates

• First Submitted: July 4, 2026
• First Submitted That Met QC Criteria: July 4, 2026
• First Posted (Actual): July 9, 2026

Study Record Updates

• Last Update Posted (Actual): July 9, 2026
• Last Update Submitted That Met QC Criteria: July 4, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: allogeneic hematopoietic stem cell transplantation; healthy allogeneic hematopoietic stem cell donor; granulocyte colony-stimulating factor (G-CSF)
• Additional Relevant MeSH Terms: Peptides; Amino Acids, Peptides, and Proteins; Proteins; Biological Factors; Carbohydrates; Intercellular Signaling Peptides and Proteins; Glycoproteins; Glycoconjugates; Colony-Stimulating Factors; Hematopoietic Cell Growth Factors; Cytokines; Granulocyte Colony-Stimulating Factor
• Other Study ID Numbers: ZJU-GCSF

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: We plan to share de-identified individual participant data (IPD) collected throughout the trial, including baseline donor characteristics, daily peripheral blood CD34⁺ cell counts, apheresis product immune cell subsets, donor adverse events, recipient engraftment times, engraftment rates, and overall survival data at 2 and 5 years. IPD will be made available upon reasonable request to the principal investigator, after the primary results are published, via a secure data repository (e.g., Zenodo or institutional data archive)Access will be granted for pre-specified research purposes only, and requestors must sign a data access agreement.
• IPD Sharing Time Frame: IPD will be made available upon reasonable request to the principal investigator, after the primary results are published, via a secure data repository (e.g., Zenodo or institutional data archive).
• IPD Sharing Access Criteria: IPD will be made available upon reasonable request to the principal investigator, after the primary results are published, via a secure data repository (e.g., Zenodo or institutional data archive). A data dictionary and study protocol will be provided alongside the data. Access will be granted for pre-specified research purposes only, and requestors must sign a data access agreement.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF; CSR

Drug and device information, study documents

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