Clinical trial Interventional Ages 40 and up Men only

Autologous Transplantation of Human Cryopreserved Testis Tissue

Run by Herlev and Gentofte Hospital · NCT07364409 · Data updated 2026-11-12

Fully enrolled, still running. This study is not taking new participants. Its registered completion date is 2025-12-17.

For pre-pubertal boys undergoing gonadotoxic therapies, freezing immature testicular tissue (ITT) containing spermatogonial stem cells (SSCs) is currently the only option to potentially preserve future fertility. This experimental clinical study aims to provide proof-of-concept that frozen-thawed, ectopically autotransplanted adult human testicular tissue can support spermatogenesis in healthy adult men.

Quick facts

Study typeInterventional
Ages40 Years and up
SexMen only
Enrollment5 (actual)
SponsorHerlev and Gentofte Hospital
Academic / other
Drugs / interventionsAutologous Transplantation of Testis Tissue
Locations1 site (Denmark)
Trial IDNCT07364409 on ClinicalTrials.gov

What this trial studies

As of 2025, more than 3,000 pre-pubertal boys worldwide have cryopreserved immature testicular tissue, and the number of centers offering this fertility preservation option prior to gonadotoxic therapies continues to grow. The most advanced strategy for future fertility restoration is the ectopic autologous transplantation of frozen-thawed ITT, allowing the tissue to mature, initiate spermatogenesis, and ultimately provide sperm for assisted fertility treatments. However, the absence of human data and the preservation of ITT samples for later clinical trials have so far hindered clinical translation. To address this knowledge gap, the investigators will conduct a proof-of-concept study involving five healthy adult participants with normal spermatogenesis who have naturally conceived children and do not desire additional biological offspring. Participants will be recruited from the Department of Urology, Copenhagen University Hospital, Herlev and Gentofte Hospital. During elective hydrocele or spermatocele surgery, testicular biopsies will be collected and cryopreserved. At a later stage, the frozen-thawed tissue fragments will be autotransplanted ectopically beneath the scrotal skin. Over a six-month period, participants will undergo regular follow-up. At the end of this period, the transplanted tissue will be retrieved and evaluated for the presence of sperm. If spermatozoa are identified, their genetic stability will also be assessed. This study will generate essential da…

Who can join: the full rules

Show full inclusion / exclusion criteria
Men referred to the Department of Urology at Herlev and Gentofte Hospital for the treatment of hydrocele or spermatocele were provided with detailed information about the study and invited to participate. Written study information was distributed, and a mandatory reflection period of at least 24 hours was observed prior to obtaining consent.

Inclusion Criteria:

* Age ≥ 40 years
* Scheduled for an elective hydrocele or spermatocele surgery
* Willing to have a testis biopsy taken during the planned surgery
* At least one biological child, unassisted spontaneous conception
* No current or future fertility wishes
* Written informed consent for the participation in this study

Exclusion Criteria:

* Treatment with testosterone substitution
* Bleeding disorders that render surgery too high a risk
* Other contraindications to surgery
* Unable to give informed consent
* Language difficulties that could compromise the informed consent or quality of examination

Where it's running

  • Copenhagen University Hospital - Herlev and Gentofte
    Herlev, Capital Region, Denmark

Study contacts

  • Principal investigator: Elena von Rohden, MD — Department of Urology, Copenhagen University Hospital - Herlev and Gentofte

Similar studies

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How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 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.