Ongoing Clinical Trials for Turner’s Syndrome

There are currently 6 clinical trials ongoing for Turner’s syndrome, a genetic condition affecting females characterized by the partial or complete absence of one X chromosome. These trials are investigating growth hormone therapies, hormone replacement treatments, and new approaches to managing symptoms associated with the condition. Studies are taking place across multiple European countries and are exploring treatments including vosoritide, estrogen replacement therapy in different forms, testosterone replacement therapy, and somapacitan.

Clinical trial locations

• Austria
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Belgium
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Bulgaria
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Croatia
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Denmark
  • Study on Estrogen Treatment (Oral vs. Transdermal) for Women with Turner Syndrome
  • Study on Long-Term Effects of Oral and Transdermal Estradiol Therapy in Women with Turner Syndrome
  • Study on Testosterone and Isopropyl Myristate for Women with Turner Syndrome
• Finland
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• France
  • Study of Vosoritide for Children with Turner Syndrome, Short Stature Homeobox-Containing Gene Deficiency, and Noonan Syndrome Not Responding to Growth Hormone
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Germany
  • Study of Vosoritide for Children with Turner Syndrome, Short Stature Homeobox-Containing Gene Deficiency, and Noonan Syndrome Not Responding to Growth Hormone
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Greece
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Italy
  • Study of Vosoritide for Children with Turner Syndrome, Short Stature Homeobox-Containing Gene Deficiency, and Noonan Syndrome Not Responding to Growth Hormone
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Latvia
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Lithuania
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Netherlands
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
  • Study on the Safety and Effectiveness of Somapacitan for Children with Short Stature Due to Noonan Syndrome, Turner Syndrome, Small for Gestational Age, or Idiopathic Short Stature
• Poland
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
  • Study on the Safety and Effectiveness of Somapacitan for Children with Short Stature Due to Noonan Syndrome, Turner Syndrome, Small for Gestational Age, or Idiopathic Short Stature
• Portugal
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Slovenia
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
• Spain
  • Study of Vosoritide for Children with Turner Syndrome, Short Stature Homeobox-Containing Gene Deficiency, and Noonan Syndrome Not Responding to Growth Hormone
  • Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature
  • Study on the Safety and Effectiveness of Somapacitan for Children with Short Stature Due to Noonan Syndrome, Turner Syndrome, Small for Gestational Age, or Idiopathic Short Stature

Study of Vosoritide for Children with Turner Syndrome, Short Stature Homeobox-Containing Gene Deficiency, and Noonan Syndrome Not Responding to Growth Hormone

This trial is investigating vosoritide as a potential treatment for children with growth-related conditions who have not responded adequately to human growth hormone therapy. The study compares different doses of vosoritide with continued hGH treatment.

Who can join: Children must be at least 3 years old and younger than 10 years for females or 11 years for males. They need a genetically confirmed diagnosis of Turner syndrome, SHOX deficiency, or Noonan syndrome. Participants must have a height Z-score of -2.00 or lower, be at Tanner Stage 1, and have received continuous hGH treatment for at least 1 year before joining. Importantly, they must have shown an inadequate response to previous hGH treatment.

Who cannot join: Children without one of the specified genetic conditions cannot participate. The trial is open to both males and females within the specified age ranges.

Study focus: The trial evaluates how different doses of vosoritide affect growth in children compared to continued hGH treatment. After an initial assessment and baseline growth phase, participants are randomly assigned to either continue hGH or switch to one of three doses of vosoritide. The treatment phase lasts six months initially, with an extended phase of up to 24 months. Regular assessments monitor growth, height Z-scores, and potential side effects.

Investigational drugs: Vosoritide is administered through subcutaneous injection. It works by targeting a specific pathway in the body that regulates bone growth. Human growth hormone continues to be used as the comparison treatment.

Study on Estrogen Treatment (Oral vs. Transdermal) for Women with Turner Syndrome

This Danish trial compares two different forms of estradiol hormone therapy to determine which is more effective for managing symptoms in women with the condition.

Who can join: Women must be between 18 and 50 years old with a confirmed diagnosis. They must already be receiving estrogen treatment. Healthy female controls are also needed who are previously healthy, not taking any medication or contraceptive pills, and have no mental or psychiatric disorders.

Who cannot join: Men cannot participate. Only females within the specified age range are eligible.

Study focus: The trial compares oral estradiol taken as Estrofem tablets with transdermal estradiol applied as Divigel gel. Both contain the same active substance but are administered differently. The study monitors hormone levels, particularly luteinizing hormone and follicle-stimulating hormone, to assess how the body responds to each treatment form. The study lasts up to 14 days.

Investigational drugs: Estradiol is tested in both oral and transdermal forms. This hormone is crucial for female development and reproductive health, binding to estrogen receptors to regulate various body functions.

Study on Long-Term Effects of Oral and Transdermal Estradiol Therapy in Women with Turner Syndrome

Another Danish study examines the long-term effects of two forms of estrogen replacement therapy on various health aspects including hormone levels, heart health, and overall physical well-being.

Who can join: Women aged 18 to 50 with a confirmed diagnosis who are already receiving estrogen treatment. Healthy female controls are also recruited who must be previously healthy, not taking medications or contraceptive pills, and free from mental or psychiatric disorders.

Who cannot join: Men are not eligible. Only females within the specified age range can participate.

Study focus: This longer-term study compares oral Estrofem tablets with transdermal Divigel gel over six months for each treatment type. After an initial assessment and washout period, participants receive oral estrogen therapy for six months, followed by mid-study assessment, then switch to transdermal therapy for another six months. The trial monitors body composition, cardiovascular status, muscle strength, bone density, and quality of life.

Investigational drugs: Both oral and transdermal estradiol are being evaluated for their long-term effects on metabolism, cardiovascular health, and overall well-being.

Study on Testosterone and Isopropyl Myristate for Women with Turner Syndrome

This Danish trial studies testosterone replacement therapy alongside estrogen replacement therapy to understand its effects on various health parameters.

Who can join: Women aged 18 to 50 with any type of the syndrome who are currently receiving estrogen replacement therapy and can speak Danish.

Who cannot join: Men cannot participate. Women outside the specified age range are not eligible.

Study focus: The study examines how testosterone replacement therapy, used alongside estrogen therapy, impacts hormone levels, heart health, brain function, and overall physical well-being. Participants use Androgel, a transdermal gel applied to the skin, for up to 12 months. The trial includes regular monitoring through DXA scans measuring body composition, along with assessments of quality of life, inflammatory markers, and other health indicators. Some participants receive a placebo for comparison.

Investigational drugs: Testosterone delivered through a transdermal patch allows gradual hormone entry into the bloodstream, mimicking natural release patterns.

Study Comparing Somapacitan and Somatropin for Growth in Children with Short Stature Due to Small for Gestational Age, Turner Syndrome, Noonan Syndrome, or Idiopathic Short Stature

This large multinational study across 16 European countries tests whether once-weekly somapacitan is as effective as daily Norditropin for promoting growth in children with various growth-related conditions.

Who can join: Children must not have had previous growth-promoting therapy. For those born small for gestational age, boys must be 2 years 26 weeks to younger than 11 years with testis volume below 4 mL, while girls must be 2 years 26 weeks to younger than 10 years without breast development. For those with Turner syndrome, girls must be 2 years 26 weeks to younger than 10 years with confirmed diagnosis and no breast development. For Noonan syndrome, boys and girls follow similar age and development criteria as SGA patients. For idiopathic short stature, children must be prepubertal with specific bone age requirements.

Who cannot join: Children without the specified short stature conditions, those outside the age ranges, those with interfering medical conditions, those on growth-affecting medications, those with previous growth hormone therapy, those with medication allergies, or those unable to comply with study procedures.

Study focus: After initial assessment and baseline measurements, participants are randomly assigned to receive either once-weekly somapacitan or continue with daily Norditropin. The primary evaluation occurs at six months, with an extended treatment phase lasting up to 24 months. Growth is carefully monitored through height velocity measurements, bone age changes, and various blood markers related to growth.

Investigational drugs: Somapacitan is given once weekly via subcutaneous injection using a pre-filled pen. Norditropin is administered daily, also by injection. Both are growth hormone therapies designed to stimulate growth in children.

Study on the Safety and Effectiveness of Somapacitan for Children with Short Stature Due to Noonan Syndrome, Turner Syndrome, Small for Gestational Age, or Idiopathic Short Stature

This trial in Poland, Spain, and the Netherlands focuses specifically on evaluating the safety and effectiveness of somapacitan for children with growth difficulties.

Who can join: Children born small for gestational age according to national standards, or girls with confirmed Turner syndrome, or children with Noonan syndrome diagnosed according to local clinical practice, or children with idiopathic short stature. All participants must be within specific age ranges at screening and have open epiphyses, meaning their bone growth plates are still open and allow for continued growth.

Who cannot join: Children with significant medical conditions that could interfere with the study, those who have had growth hormone treatment within the last 6 months, those with allergies to the study medication, those currently in another trial, those with a history of cancer or serious illness, those unable to comply with procedures, or those deemed unsuitable by the investigator.

Study focus: After an initial visit with physical examination, participants receive weekly somapacitan injections under the skin at a dose of 15 mg in 1.5 ml of solution. Weekly follow-ups monitor response and check for side effects. A comprehensive mid-study evaluation occurs at approximately 26 weeks, with long-term follow-up continuing until 156 weeks. The study carefully tracks the number of adverse events and measures growth progress throughout the treatment period.

Investigational drugs: Somapacitan is given once weekly to help children grow taller. It mimics natural growth hormone and is being tested in children who are shorter than usual for their age due to various conditions.

Summary

The six ongoing clinical trials for Turner’s syndrome reflect two distinct research priorities: growth promotion in children and hormone replacement therapy optimization in adult women.

Three trials focus on Denmark, examining different aspects of hormone replacement therapy in adult women. These studies compare oral versus transdermal estrogen delivery and explore testosterone supplementation alongside estrogen therapy. This concentration suggests Denmark is a center of expertise for hormone management in this condition.

Growth-focused trials are more geographically diverse. The vosoritide study spans Germany, France, Spain, and Italy, while the large somapacitan comparison trial operates across 16 European countries. A smaller somapacitan safety study takes place in Poland, Spain, and the Netherlands.

Somapacitan, a once-weekly growth hormone, features in two trials, reflecting significant interest in this newer therapy. Traditional daily growth hormone and the experimental drug vosoritide are also under investigation. All growth trials include children with Turner syndrome alongside other growth-related conditions, allowing researchers to gather broader evidence while studying this specific population.

The hormone replacement trials exclusively focus on women with Turner syndrome, examining how different delivery methods affect cardiovascular health, bone density, metabolism, and quality of life. These studies address lifelong health management needs for women with the condition.