Balancing sex hormones to improve health in men with Klinefelter syndrome

Dissecting the Importance of Sex Steroids Balance for Metabolic and Reproductive Health in Men With Klinefelter Syndrome: a Randomized Controlled Study

Phase 3 Interventional University of Lausanne Hospitals · NCT05586802

This study is testing if a new hormone treatment can improve health and sperm production in men with Klinefelter syndrome by balancing their sex hormones and looking at weight loss effects.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment150 (estimated)
Ages16 Years to 65 Years
SexMale
SponsorUniversity of Lausanne Hospitals Academic / other
Locations1 site (Lausanne)
Trial IDNCT05586802 on ClinicalTrials.gov

What this trial studies

This study aims to evaluate the effects of aromatase inhibitors on metabolic health and sperm production in men diagnosed with Klinefelter syndrome. It will compare the outcomes of hormone modulation with standard treatments, focusing on the balance of testosterone and estradiol. Additionally, the study will explore the impact of weight loss through semaglutide and the role of human chorionic gonadotropin in enhancing testosterone levels and fertility. A multi-omic analysis will also be conducted to understand the diverse reproductive and metabolic profiles in this population.

Who should consider this trial

Good fit: Ideal candidates include men aged 16-65 with a diagnosis of Klinefelter syndrome, either seeking fertility preservation or experiencing hypogonadism and metabolic risks.

Not a fit: Patients with contraindications to testosterone therapies or those with terminal diseases may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved metabolic health and fertility options for men with Klinefelter syndrome.

How similar studies have performed: While there is ongoing research in hormone modulation for Klinefelter syndrome, this specific approach combining multiple interventions is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

-Diagnosis of Klinefelter syndrome (47,XXY or mosaicism)

Design 1:

* Age range: 16-40 years old
* Intention to become parent or interest in fertility preservation
* Confirmed azoospermia (lack of spermatozoids) after centrifugation of one semen sample

Design 2:

* Age range: 18-65 years old
* No interest in fertility or fertility preservation
* Hypogonadism at diagnosis or after wash-out of testosterone replacement therapy
* High metabolic risk defined as overweight (BMI 25-28 kg/m2) and insulin resistance (HOMA-IR \> 2.6)

Exclusion Criteria:

* Contraindications to testosterone-rising therapies (prostate or breast cancer, PSA \> 4 µg/l, active liver disease, symptomatic heart disease)
* Decreased life expectancy due to terminal disease
* Known or suspected non-compliance, drug or alcohol abuse
* Inability to follow the procedures of the study (language problems, severe psychological or mental disorders)

Where this trial is running

Lausanne

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 Klinefelter SyndromeMetabolic syndromeInfertilityAromataseTestosterone/estradiol ratiomTESE biopsyGLP1 agonists
Last reviewed 2026-06-10 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.