Growth hormone (GH) therapy has transformed the lives of people with Prader-Willi syndrome (PWS). For more than two decades, growth hormone treatment has been recognized as a cornerstone of care in children with PWS, improving not only height but also body composition, strength, cognition, metabolism, and quality of life.
Growth Hormone Therapy in Children with PWS: A Proven Success
The U.S. Food and Drug Administration approved growth hormone therapy for children with PWS in 2000. Since then, numerous studies have shown that treatment can:
- Improve growth and normalize height
- Increase muscle mass and reduce body fat
- Improve metabolism and physical endurance
- Support cognitive development and adaptive functioning
- Enhance overall health and quality of life
Today, growth hormone therapy is widely considered a standard of care for children with PWS.
What are the Benefits of Growth Hormone Therapy for Adults with PWS?
While adults are no longer growing taller, growth hormone continues to play an essential role in maintaining healthy body composition, metabolism, physical function, and overall well-being.
Over the past two decades, multiple clinical trials have demonstrated that growth hormone treatment in adults with PWS can:
- Increase lean body mass
- Reduce body fat mass
- Improve muscle strength and physical performance
- Support exercise capacity and endurance
- Improve cardiovascular risk factors
- Normalize IGF-1 levels
- Support cognitive function and emotional well-being
- Improve overall quality of life
A 2021 meta-analysis combining data from multiple studies confirmed that growth hormone treatment consistently improves body composition in adults with PWS and has a favorable safety profile when appropriately monitored.
Long-term studies have shown that these benefits are sustained over time, helping adults with PWS maintain healthier body composition and physical functioning throughout adulthood.
Growth Hormone Treatment Is Generally Safe
More than two decades of clinical experience and research have demonstrated that growth hormone therapy is generally safe for individuals with Prader-Willi syndrome when prescribed and monitored appropriately. As with any long-term treatment, regular follow-up with an endocrinologist is important to ensure therapy remains safe, effective, and tailored to each individual's needs.
International Experts Support Growth Hormone Treatment for Adults with PWS
In 2013, an international panel of experts convened to review growth hormone treatment in PWS. Their consensus statement concluded that adults with PWS should be considered for growth hormone treatment following appropriate medical evaluation and monitoring. More recently, the International Prader-Willi Syndrome Organisation (IPWSO) Clinical and Scientific Advisory Board issued a position statement calling for broader access to growth hormone treatment for adults with PWS, noting that the scientific evidence supporting its use extends well beyond childhood.
Despite these recommendations, many adults with PWS lose access to treatment simply because they reach adulthood.
Why Are Adults Losing Access to Growth Hormone Treatment?
Despite a substantial body of scientific evidence demonstrating ongoing benefits in adulthood, many individuals with PWS lose access to growth hormone treatment as they age. The result is a significant gap between what the research supports and what many adults with PWS are able to access through their insurance coverage.
One of the most significant barriers is the requirement that adults meet traditional diagnostic criteria for adult growth hormone deficiency before insurance companies will approve treatment. This requirement is problematic because PWS is fundamentally a disorder of hypothalamic dysfunction. The hypothalamus plays a critical role in regulating growth hormone secretion, appetite, metabolism, sleep, temperature regulation, and many other physiological functions affected in PWS.
As a result, many adults with PWS who demonstrate clear clinical benefits from growth hormone therapy do not meet traditional testing criteria for adult growth hormone deficiency. Standard stimulation tests were developed for other conditions and may not accurately reflect the unique neuroendocrine abnormalities present in PWS.
Unfortunately, insurance companies often rely on these testing requirements when making coverage decisions, creating barriers to treatment despite extensive evidence demonstrating clinical benefit. The consequence is that many individuals discontinue growth hormone therapy during late adolescence or early adulthood—not because the treatment is no longer needed, but because coverage is denied. This loss of access occurs despite evidence showing continued benefits on body composition, physical function, metabolic health, and overall quality of life.
Why Does Continued Access to Growth Hormone Treatment Matter?
Adults with PWS face lifelong challenges related to abnormal body composition, reduced muscle mass, decreased energy expenditure, and increased risk of obesity-related complications.
Growth hormone therapy helps address many of these underlying biological challenges. By maintaining healthier body composition and physical functioning, continued treatment may help reduce long-term health complications, preserve independence, and improve quality of life.
For many adults with PWS, growth hormone is not simply a treatment for growth—it is a treatment for lifelong health.
Expanding Growth Hormone Therapy for Adults with PWS
Given the substantial evidence supporting the benefits and safety of growth hormone treatment in adults with PWS, there is a strong case for expanding access and modernizing coverage policies.
Leading experts and advocacy organizations support:
- Recognition of the benefits of growth hormone therapy beyond childhood growth
- Greater consideration of the unique neuroendocrine features of PWS when making treatment decisions
- Elimination of unnecessary barriers that prevent adults with PWS from accessing treatment
- Expanded regulatory approval and insurance coverage for adults with PWS
The scientific evidence is clear: growth hormone therapy provides meaningful benefits throughout the lifespan for many individuals with Prader-Willi syndrome.
It is time for healthcare systems, insurers, regulators, and pharmaceutical companies to ensure that adults with PWS can continue accessing a therapy that has the potential to improve their health, function, and quality of life.
Learn more about the importance of growth hormone therapy for PWS.
Key References
Deal CL, Tony M, Höybye C, et al. Growth Hormone Research Society workshop summary: Consensus guidelines for recombinant human growth hormone therapy in Prader-Willi syndrome. Journal of Clinical Endocrinology & Metabolism. 2013.
Rosenberg AGW, et al. Growth hormone treatment for adults with Prader-Willi syndrome: A meta-analysis. Journal of Clinical Endocrinology & Metabolism. 2021.
Höybye C, Holland AJ, Driscoll DJ. Time for a general approval of growth hormone treatment in adults with Prader-Willi syndrome. Orphanet Journal of Rare Diseases. 2021.
Sode-Carlsen R, et al. One year of growth hormone treatment in adults with Prader-Willi syndrome improves body composition: Results from a randomized, placebo-controlled study. Journal of Clinical Endocrinology & Metabolism. 2010.
Kupens (2016b) Kuppens RJ, Bakker NE, Siemensma EP, et al. Beneficial effects of GH in young adults with Prader-Willi syndrome: a 2-year crossover trial. J Clin Endocrinol Metab. 2016;101(11):4110-4116.
Hoybye (2003): Höybye C, Hilding A, Jacobsson H, Thorén M. Growth hormone treatment improves body composition in adults with Prader-Willi syndrome. Clin Endocrinol (Oxf). 2003;58(5):653-661.
Damen (2020a) Damen L, Donze SH, Kuppens RJ, et al. Three years of growth hormone treatment in young adults with Prader-Willi syndrome: sustained positive effects on body composition. Orphanet J Rare Dis. 2020;15(1):163.
Lafortuna (2014) Lafortuna CL, Minocci A, Capodaglio P, et al. Skeletal muscle characteristics and motor performance after 2-year growth hormone treatment in adults with prader-willi syndrome. J Clin Endocrinol Metab. 2014;99(5):1816-1824.
Mogul (2008) Mogul HR, Lee PD, Whitman BY, et al. Growth hormone treatment of adults with Prader-Willi syndrome and growth hormone deficiency improves lean body mass, fractional body fat, and serum triiodothyronine without glucose impairment: results from the United States multicenter trial. J Clin Endocrinol Metab. 2008;93(4):1238-1245.
