CancerNCT05414045
Autologous Testicular Tissue Transplantation
A study testing Autologous testicular tissue transplantation of prepubertal frozen testicular tissue in people with Cancer and Sickle Cell Thalassemia, run by Universitair Ziekenhuis Brussel at 1 site in Belgium.
Trial summary
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells in case of imminent gonadotoxic treatment during childhood. In case of total azoospermia or absence of spermatozoa that can be used for intra-cytoplasmic injection (ICSI) in adulthood, the investigators intend to… Read more about this study
- Who is it for?
- Ages 18 to 50 years, men only
- Conditions the study is for
- Cancer, Sickle Cell Thalassemia, Hematologic Diseases
- What is being tested?
- Autologous testicular tissue transplantation of prepubertal frozen testicular tissue
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 5 participants
- Where
- 1 siteBelgium
- Study dates
- 22 Nov 2024to 29 Oct 2030
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 50 years
- Men only
- No healthy volunteers
- Adult
Who may be able to join
- 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
Show all 9Show fewer
- 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
Who cannot join
- 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
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium1 site, 1 recruiting
- Recruiting
UZ Brussel Centre for Reproductive Medicine
Brussels, 1090
About this study
Official title: Autologous Testicular Tissue Transplantation for Fertility Restoration
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells in case of imminent gonadotoxic treatment during childhood. In case of total azoospermia or absence of spermatozoa that can be used for intra-cytoplasmic injection (ICSI) in adulthood, the investigators intend to perform the first in men autologous testicular tissue transplantation to restore fertility.
Read the detailed description
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells. In 2002, the University hospital in Brussels (UZB) was the first hospital worldwide to offer testicular tissue cryobanking for fertility preservation in boys and ado-lescents. Since then, several other centers in Europe and USA have implemented similar fertility preservation programs. However, up till now, autologous transplantations of cryopreserved testicular tissue have not been performed yet.
As soon as a patient returns to the Centre for Reproductive Medicine at UZB with the request to transplant the preserved testicular tissue, the investigators will first analyse semen and blood. If spermatozoa are found in their semen, men can immediately enroll in standard care for natural conception, intra-uterine insemination (IUI), in-vitro fertilization (IVF) or intra-cytoplasmic injection (ICSI). However, if no spermatozoa suitable for ICSI are detected in the ejaculate, the investigators intend to propose and eventually perform autologous testicular tissue transplantation with the primary objective being to restore spermatogenesis and fertility.
- Conditions
- Cancer, Sickle Cell Thalassemia, Hematologic Diseases
- Being tested
- Autologous testicular tissue transplantation of prepubertal frozen testicular tissue
- Medical subject headings
- Neoplasms, Hematologic Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Autologous testicular tissue transplantation of prepubertal frozen testicular tissueProcedure or surgery
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells.
If no spermatozoa suitable for ICSI are detected in the ejaculate, the investigators will perform autologous testicular tissue transplantation with the primary objective being to restore spermatogenesis and fertility.
| Study group | Role | What they receive |
|---|---|---|
| Patients | Experimental | Not described Receives: Procedure: Autologous testicular tissue transplantation of prepubertal frozen testicular tissue |
What is being measured
The primary outcome is the main question the study is designed to answer.
Restoration of spermatogenesis and fertility by performing an autologous testicular tissue transplantation. Primary endpoint is the presence of spermatozoa in the graft.
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells.
If the patient has no spermatozoa suitable for ICSI in the ejaculate in adulthood, the investigators will perform autologous testicular tissue transplantation with the primary objective being to restore spermatogenesis and fertility.
Grafting will be performed intra-testicular and intrascrotal for each patient. Grafts will be removed 12 months after grafting.
Primary endpoint is the presence of spermatozoa in the grafted tissue. In the IVF laboratory mechanical mincing and enzymatic digestion will be performed on the tissue to find spermatozoa. If spermatozoa are present concentration and motility will be available.
Measured: Graft-removal of intratesticular and intrascrotal grafts is planned 12 months after grafting.
Secondary outcomes (5)
Histological study to define the optimal transplantation site
The presence of sperm-generating stem cells, as well as their possible maturation to sperm cells will be evaluated through available and validated microscopic staining techniques applied to the testicular tissue. The maturity of other, non-sperm-generating testicular cells (Sertoli cells and Leydig cells) will also be evaluated. The results from tissue fragments transplanted to the testicle will be compared to the results from the tissue fragments transplanted to the scrotum. During the removal procedure of the transplanted fragments, a control biopsy (TESE) will be performed on the contra-lateral testicle (the one on which no transplantation was performed).
Measured: Graft-removal of intratesticular grafts and intrascrotal grafts are planned 12 months after initial grafting. Histological study will be performed 12 months after initial grafting
Imaging study
The investigators will study the possibility of analyzing the growth of the transplanted fragments and the development of sperm cell production in these fragments by using ultrasound and Doppler techniques in a non-invasive way. Ultrasound will be performed 3, 6, 9 and 12 months after grafting. These findings will be compared to the findings of the semen and blood analysis and the clinical examination.
Measured: Each patient in the study will be followed-up after screening during a period of 12 months post-grafting on 3, 6, 9 and 12 months after initial grafting.
Endocrinological (hormonal) study
The investigators plan a follow-up of the functionality of the transplanted tissue by performing blood analyses with LH (IU/L), FSH (IU/L), testosterone (ng/L), Inhibine B (ng/L) and Insulin-like factor 3 (INSL3, ng/ml).
Blood analyses will be repeated 3, 6, 9 and 12 months after the transplantation procedure.
Measured: Each patient in the study will be followed-up after screening during a period of 12 months post-grafting on 3, 6, 9 and 12 months after initial grafting.
Biomarker Study
As an exploratory part of this study, the investigators will study the possibility to predict the presence of testicular spermatogenesis in a non-invasive way (by semen and/or urine samples). If different biomarkers could be identified specificaly for the different stages of spermatogenesis, the development of the transplanted biopsies could be monitored this way. For this study, a urine and semen sample will be needed 3, 6, 9 and 12 months after the transplantation procedure.
Measured: Each patient in the study will be followed-up after screening during a period of 12 months post-grafting on 3, 6, 9 and 12 months after initial grafting.
Complications
Each patient in the study will be followed-up during a period of 15 months after initial grafting or 3 months after graft-removal to report any complication(s) of the procedures.
Measured: Each patient in the study will be follow-up after screening during a period of 15 months post-grafting.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jun 2022
- Study start22 Nov 2024
- Primary completion29 Jul 2030 (estimated)
- Study completion29 Oct 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for CancerStudies of the same condition, open and under way.
- More trials run by Universitair Ziekenhuis BrusselThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- All eligible patients for the study will have the same treatment: autologous testicular tissue transplantation with testicular tissue containing spermatogonial stem cells frozen at pre-pubertal age. Transplantation will be performed subcutaneously in the scrotum and intra-testicular.
- Masking
- None (open label)
- Enrolment
- 5 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universitair Ziekenhuis Brussel
- Sponsor type
- University, hospital or other
- Collaborators
- Vrije Universiteit Brussel
- Responsible party
- Sponsor
- Investigators
- Veerle Vloeberghs, MD, Principal investigator, CRG UZ Brussel
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05414045
- Sponsor's protocol ID
- 2019-477
- Status last verified
- Apr 2026
- First submitted
- 17 Feb 2022
- Last updated
- 23 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 23 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Autologous Testicular Tissue Transplantation for Fertility Restoration
- ClinicalTrials.gov ID
- NCT05414045
- Acronym / sponsor ID
- 2019-477
- Conditions
- Cancer, Sickle Cell Thalassemia, Hematologic Diseases
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 5 participants (estimated)
- Lead sponsor
- Universitair Ziekenhuis BrusselUniversity, hospital or other
- Collaborators
- Vrije Universiteit Brussel
- Study start
- 22 Nov 2024 (actual)
- Primary completion
- 29 Jul 2030 (estimated)
- Study completion
- 29 Oct 2030 (estimated)
- First posted
- 10 Jun 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells in case of imminent gonadotoxic treatment during childhood. In case of total azoospermia or absence of spermatozoa that can be used for intra-cytoplasmic injection (ICSI) in adulthood, the investigators intend to perform the first in men autologous testicular tissue transplantation to restore fertility.
Detailed description
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells. In 2002, the University hospital in Brussels (UZB) was the first hospital worldwide to offer testicular tissue cryobanking for fertility preservation in boys and ado-lescents. Since then, several other centers in Europe and USA have implemented similar fertility preservation programs. However, up till now, autologous transplantations of cryopreserved testicular tissue have not been performed yet.
As soon as a patient returns to the Centre for Reproductive Medicine at UZB with the request to transplant the preserved testicular tissue, the investigators will first analyse semen and blood. If spermatozoa are found in their semen, men can immediately enroll in standard care for natural conception, intra-uterine insemination (IUI), in-vitro fertilization (IVF) or intra-cytoplasmic injection (ICSI). However, if no spermatozoa suitable for ICSI are detected in the ejaculate, the investigators intend to propose and eventually perform autologous testicular tissue transplantation with the primary objective being to restore spermatogenesis and fertility.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- All eligible patients for the study will have the same treatment: autologous testicular tissue transplantation with testicular tissue containing spermatogonial stem cells frozen at pre-pubertal age. Transplantation will be performed subcutaneously in the scrotum and intra-testicular.
| Arm | Type | Receives |
|---|---|---|
| Patients | Experimental | Procedure: Autologous testicular tissue transplantation of prepubertal frozen testicular tissue |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (9 listed)
- 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
Key exclusion criteria (6 listed)
- 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)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Autologous testicular tissue transplantation of prepubertal frozen testicular tissueFreezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells. If no spermatozoa suitable for ICSI are detected in the ejaculate, the investigators will perform autologous testicular tissue transplantation with the primary objective being to restore spermatogenesis and fertility. | Procedure or surgery | Patients |
Primary outcome
Restoration of spermatogenesis and fertility by performing an autologous testicular tissue transplantation. Primary endpoint is the presence of spermatozoa in the graft.
Time frame: Graft-removal of intratesticular and intrascrotal grafts is planned 12 months after grafting.
Freezing testicular tissue of prepubertal boys is a method for preserving spermatogonial stem cells. If the patient has no spermatozoa suitable for ICSI in the ejaculate in adulthood, the investigators will perform autologous testicular tissue transplantation with the primary objective being to restore spermatogenesis and fertility. Grafting will be performed intra-testicular and intrascrotal for each patient. Grafts will be removed 12 months after grafting. Primary endpoint is the presence of spermatozoa in the grafted tissue. In the IVF laboratory mechanical mincing and enzymatic digestion will be performed on the tissue to find spermatozoa. If spermatozoa are present concentration and motility will be available.
5 secondary outcomes
Histological study to define the optimal transplantation site
Time frame: Graft-removal of intratesticular grafts and intrascrotal grafts are planned 12 months after initial grafting. Histological study will be performed 12 months after initial grafting
Imaging study
Time frame: Each patient in the study will be followed-up after screening during a period of 12 months post-grafting on 3, 6, 9 and 12 months after initial grafting.
Endocrinological (hormonal) study
Time frame: Each patient in the study will be followed-up after screening during a period of 12 months post-grafting on 3, 6, 9 and 12 months after initial grafting.
Biomarker Study
Time frame: Each patient in the study will be followed-up after screening during a period of 12 months post-grafting on 3, 6, 9 and 12 months after initial grafting.
Complications
Time frame: Each patient in the study will be follow-up after screening during a period of 15 months post-grafting.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Apr 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Veerle Vloeberghs, MD principal investigator
CRG UZ Brussel
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Autologous testicular tissue transplantation of prepubertal frozen testicular tissue in people with Cancer and Sickle Cell Thalassemia, run by Universitair Ziekenhuis Brussel at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 23 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Veerle Vloeberghs, MD (003224776699, veerle.vloeberghs@uzbrussel.be), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Restoration of spermatogenesis and fertility by performing an autologous testicular tissue transplantation. Primary endpoint is the presence of spermatozoa in the graft. (time frame: Graft-removal of intratesticular and intrascrotal grafts is planned 12 months after grafting.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Apr 2026; AzTrials last refreshed its copy on 6 Nov 2026.