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Recruiting Phase 4 NCT06294990

NCT06294990 Klinefelter Syndrome and Testosterone Treatment in Puberty

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Clinical Trial Summary
NCT ID NCT06294990
Status Recruiting
Phase Phase 4
Sponsor Lise Aksglæde
Condition Klinefelter Syndrome
Study Type INTERVENTIONAL
Enrollment 32 participants
Start Date 2024-08-15
Primary Completion 2029-12-31

Eligibility & Interventions

Sex Male only
Min Age 10 Years
Max Age 14 Years
Study Type INTERVENTIONAL
Interventions
Testosterone gelPlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 4 studies follow an already-approved treatment in real-world conditions to monitor long-term safety and effectiveness.

This trial targets 32 participants in total. It began in 2024-08-15 with a primary completion date of 2029-12-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

The goal of this randomized clinical trial is to study the effect of testosterone replacement therapy during puberty in boys with Klinefelter syndrome (KS, 47,XXY). The main questions to answer are how treatment with testosterone will affect body fat mass, lipid and glucose metabolism, growth and body proportions, bone mineralization as well as effects on neurocognitive development and emotional and social difficulties. Participants will be randomized to two years treatment with testosterone or placebo.

Eligibility Criteria

Inclusion Criteria: * 47,XXY Klinefelter syndrome * Age 10-14 years at inclusion * Luteinizing Hormone \> +2 standard deviations (SD) by ultrasensitive luteinizing hormone assay * Free Testosterone\<+2 standard deviations * Signed consent from parents Exclusion Criteria: * Previous or ongoing T treatment except for TRT because of micropenis * Contraindications to testosterone treatment known hypersensitivity to testosterone or to any other constituent of the gel known or suspected prostatic cancer or breast carcinoma * Participation in any other clinical trial

Contact & Investigator

Central Contact

Lise Aksglaede, MD

✉ lise.aksglaede@regionh.dk

📞 +45 35455064

Principal Investigator

Lise Aksglaede, MD

PRINCIPAL INVESTIGATOR

Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark

Frequently Asked Questions

Who can join the NCT06294990 clinical trial?

This trial is open to male participants only, aged 10 Years or older, up to 14 Years, studying Klinefelter Syndrome. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06294990 trial and what does that mean for participants?

Phase 4 studies are conducted after a treatment has been approved. They monitor long-term safety and real-world effectiveness in a broader patient population.

Is NCT06294990 currently recruiting?

Yes, NCT06294990 is actively recruiting participants. Contact the research team at lise.aksglaede@regionh.dk for enrollment information.

Where is the NCT06294990 trial being conducted?

This trial is being conducted at Copenhagen, Denmark.

Who is sponsoring the NCT06294990 clinical trial?

NCT06294990 is sponsored by Lise Aksglæde. The principal investigator is Lise Aksglaede, MD at Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark. The trial plans to enroll 32 participants.

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