Younger vs. Older Donors in Allo-HSCT: TTE

NCT07666568 | Not Yet Recruiting

• 1 other identifier: TTE DONOR AGE
• Study Type: observational
• Target: 5,000
• Locations: 1 country
• Sites: 1

Brief Summary

Hematopoietic stem cell transplantation is an important therapeutic approach for hematologic malignancies, and the impact of donor age on transplant outcomes remains an active area of investigation. Older donors may be associated with impaired stem cell fitness, delayed immune reconstitution, and reduced T-cell function. However, randomized controlled trials directly comparing transplant outcomes by donor age are difficult to conduct because of ethical constraints, and previous retrospective studies have yielded inconsistent findings due to confounding bias and limited causal interpretability. Target trial emulation (TTE) is a methodological framework that uses observational data to emulate the design principles of a randomized trial, thereby reducing biases such as immortal time bias, time-varying confounding, and prevalent-user bias, and improving the validity of causal inference. Therefore, this study will use a large single-center retrospective clinical cohort to perform a TTE analysis, aiming to approximate the causal framework of an randomized trial and systematically evaluate the effect of donor age on clinical outcomes after allo-HSCT, thereby providing higher-quality evidence to optimize donor selection strategies.

Conditions

A Target Trial Emulation Study; Donor Age; ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION

Outcome Measures

Primary Outcomes (1)

• Overall Survival

  Overall survival was defined as the interval between hematopoietic stem cell transplantation and death from any cause.

  From the date of transplantation to the date of death from any cause or last follow-up, assessed up to 15 years.

Study Arms (2)

Younger Donor Group

Patients who underwent allogeneic hematopoietic stem cell transplantation with donors younger than 50 years. Grouping was based on donor age recorded in retrospective clinical data.

Older Donor Group

Patients who underwent allogeneic hematopoietic stem cell transplantation with donors aged 50 years or older. Grouping was based on donor age recorded in retrospective clinical data.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

This study includes adult patients with hematologic malignancies who underwent allogeneic hematopoietic stem cell transplantation at the study center. Eligible patients will be identified from retrospective clinical records and grouped according to donor age recorded at the time of transplantation.

You may qualify if:

• Age 18 years or older.
• Diagnosis of hematologic malignancy.
• Underwent first allogeneic hematopoietic stem cell transplantation.
• HLA matching level of 0.5 or higher.
• Available donor age information.
• Available clinical follow-up and outcome data.

You may not qualify if:

• Previous autologous or allogeneic hematopoietic stem cell transplantation.
• HLA matching level below 0.5.
• Missing donor age information.
• Missing key exposure-defining or outcome-defining data required for the analysis.

Sponsors & Collaborators

• The First Affiliated Hospital of Soochow University: lead

Study Sites (1)

The First Affiliated Hospital of Soochow University

Suzhou, Jiangsu, 215000, China

Location

Central Study Contacts

Yang Xu

CONTACT

+86-512-67781850; xuyang1020@126.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 15, 2026
• First Posted: June 24, 2026
• Study Start: July 15, 2026
• Primary Completion: July 15, 2026
• Study Completion (Estimated): December 21, 2027
• Last Updated: June 24, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)