Transplanting frozen testicular tissue to restore fertility in men

Autologous Testicular Tissue Transplantation for Fertility Restoration

Not applicable Interventional Universitair Ziekenhuis Brussel · NCT05414045

This study is testing if transplanting frozen testicular tissue can help men who had cancer as boys regain their ability to father children later in life.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment5 (estimated)
Ages18 Years to 50 Years
SexMale
SponsorUniversitair Ziekenhuis Brussel Academic / other
Locations1 site (Brussels)
Trial IDNCT05414045 on ClinicalTrials.gov

What this trial studies

This study focuses on the autologous transplantation of cryopreserved testicular tissue from prepubertal boys who have undergone fertility preservation due to cancer or hematologic diseases. The aim is to restore spermatogenesis and fertility in men who experience total azoospermia in adulthood. The process involves analyzing semen and blood to determine the presence of spermatozoa, and if absent, proceeding with the transplantation of the preserved tissue. This innovative approach builds on previous fertility preservation efforts and aims to provide a viable option for men wishing to conceive after treatment.

Who should consider this trial

Good fit: Ideal candidates are men aged 18 and older who had testicular tissue cryopreserved as prepubertal boys and are now seeking to restore their fertility.

Not a fit: Patients who have not undergone testicular tissue cryopreservation or those who do not have azoospermia may not benefit from this study.

Why it matters

Potential benefit: If successful, this could enable men who are azoospermic due to prior treatments to regain their fertility and have biological children.

How similar studies have performed: While similar fertility preservation methods have been implemented, this specific approach of autologous transplantation has not been previously performed, making it a novel endeavor.

Eligibility criteria

Show full inclusion / exclusion criteria
The eligible patients opted as a prepubertal boy to enroll in the fertility preservation program and on the moment of cancer diagnosis or hematological disorder, their parents have agreed to cryopreserve testicular tissue for later autologous transplantation.

Inclusion Criteria:

* At least 18 years old
* In case of female partner, age \< 43 year
* Absence of spermatozoa that can be used for ICSI on 2 semen analyses
* Normal standardised preliminary and preoperative bloodsampling results
* Complete remission of the oncological or hematological disease
* Approval of the treating oncologist or other specialist in case of non-oncological disease as reason for the testicular tissue preservation as a child
* Risk for presence of malignant cells in testicular tissue is negligible (according to multidisciplinary assessment)
* Presence of spermatogonial stem cells (positive MAGE staining) in one or two of the thawed fragments (If absence of spermatogonial stem cells in two of the thawed fragments, the case will be discussed multidisciplinary)
* Written informed consent for the transplantation of cryopreserved testicular tissue and follow-up after the procedure and of children born eventually after this procedure

Exclusion criteria:

* Risk for presence of malignant cells in the testicular tissue
* Contra-indication for surgery
* Contra-indication for pregnancy in the female partner
* BMI \> 32
* Heavy smoking (≥10 cigarettes/day)
* Instable psychological condition

Where this trial is running

Brussels

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions CancerSickle Cell ThalassemiaHematologic Diseases
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.