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2023 Prader-Willi Syndrome- Emerging Competition & Impact!
What is Prader- Willi Syndrome? How is it manifested?
Prader-Willi syndrome is a complex genetic condition that affects many parts of the body. Prader-Willi syndrome in infants is manifested through weak muscle tone (hypotonia), feeding difficulties, poor growth, and delayed development.
Prader-Willi syndrome in children & adults is manifested through extreme hunger, which leads to chronic overeating (hyperphagia) and obesity. Some patients with Prader-Willi syndrome, particularly those with obesity, also develop type 2 diabetes. There is also mild to moderate intellectual impairment and learning disabilities including behavioural problems like temper outbursts, stubbornness, and compulsive behaviour such as picking at the skin. Sleep abnormalities can also occur.
Additional manifestations of Prader-Willi are distinctive facial features such as a narrow forehead, almond-shaped eyes, a triangular mouth, short stature and small hands and feet. Some people with Prader-Willi syndrome have unusually fair skin and light-coloured hair. Both affected males and affected females have underdeveloped genitals. Puberty is delayed or incomplete, and most affected individuals are unable to have children (infertile).
How is Prader-Willi Syndrome caused?
Prader-Willi Syndrome is caused by genetic changes on an “unstable” region of chromosome 15 that affects the regulation of gene expression, or how genes turn on and off.
There are three ways that this can happen.
PWS by Deletion- Most often, part of chromosome 15 that was inherited from the person’s father is missing, or deleted, in this critical region. This small deletion occurs in approximately 70% of cases and usually is not detectable with routine genetic analysis such as amniocentesis.
PWS by UPD- Another 30% or so of cases occur when an individual inherits two chromosome 15s from their mother and none from their father. This scenario is termed maternal uniparental disomy (UPD).
PWS by Imprinting Defect- Finally, in a very small percentage of cases (1-3%), a small genetic mutation in the Prader-Willi region causes the paternal chromosome 15 genetic material (although present) to be inactive.
How is Prader-Willi Syndrome diagnosed?
Prader-Willi Syndrome is diagnosed using a series of specialized genetic tests which includes:
DNA Methylation- The current genetic tool used to confirm PWS is called DNA methylation testing. DNA methylation testing is particularly important in patients who do not have typical symptoms or are too young to show enough features to make a symptom-based diagnosis.
Fluorescent in situ hybridization– DNA methylation testing cannot distinguish among the major genetic subtypes of PWS. Therefore, Fluorescent in situ hybridization is used which allows physicians to identify PWS patients who have a deletion in chromosome 15. However, it is not able to identify those who have uniparental disomy or an imprinting error.
High-resolution microarrays- They can detect both the size of the 15q11-q13 deletion, the most common genetic cause of PWS, as well as maternal disomy 15, are high-resolution microarrays.
Epidemiology: Prevalence & Drug Treated Cases. How many people are suffering from Prader-Willi Syndrome in the G7 countries i.e: US, Europe 5 (UK, Germany, France, Italy, Spain) and Japan?
Prader-Willi syndrome is a rare/orphan indication. As per Mellalta estimates, in the year 2022, there are approximately 66,000 people suffering from Prader-Willi syndrome in the G7 countries, while the US has approximately 17,000 people suffering from Prader-Willi syndrome.
The drug-treated cases i.e the patients who actually receive any pharmacological intervention are way lower than the disease prevalence. This is because the diagnosis of Prader-Willi syndrome requires specialized tests and dedicated medical centres, access to which is not available to everyone coupled with a lack of awareness.
Current Treatment & Medical Practices. How is Prader-Willi Syndrome treated/managed right now?
Currently, there is no cure for Prader-Willi syndrome and at best the symptoms are being managed through multi-disciplinary approaches.
For infants: Use of special nipples or tubes for feeding difficulties.
For children & adults: Strict supervision of daily food intake to manage hyperphagia (Overeating)
- Growth Hormone (GH) therapy (Norditropin by Novo Nordisk; Genotropin by Pfizer; Omnitrope by Novartis/Sandoz; Growject by JCR Pharma)
- Treatment of eye problems by a pediatric ophthalmologist
- Treatment of curvature of the spine by an orthopedist
- Sleep studies and treatment
- Physical therapy
- Behavioural therapy
- Early interventions/Special needs programs
- Sex hormone treatments and/or corrective surgery/Replacement of sex hormones
- Placement in group homes during adulthood
What are the biggest challenges the caregivers of Prader-Willi syndrome face daily?
As there is no cure for Prader-Willi syndrome, the best caregivers can do right now is to manage the symptoms.
As per Mellalta findings, the top 4 biggest challenges faced by the caregivers of patients suffering from Prader-Willi syndrome, which also presents the biggest opportunities to the pharma/biotech companies to intervene are:
- Management of hyperphagia in the patients: Reducing the hunger of Prader-Willi patients, and normalizing the patient’s behaviour near food is the biggest unmet need. Patients need to be supervised 24/7, with locked kitchen cabinets and locked refrigerators else the patients would eat to their death. The constant supervision not only isolates the patient but their caregivers as well causing lot of distress and reduced quality of life for the patients and the caregivers
- Improving metabolic health of the patients: Reducing fat composition, increasing muscle mass, improving activity and stamina
- Improving Behavioural and cognitive symptoms of the patients: These include Obsessive/compulsive behaviour, intellectual development impairment, severity and frequency of temper outburst
- Sleep abnormalities especially Excessive Day time sleepiness
The emerging treatment landscape of Prader-Willi syndrome. How are the current and upcoming companies invested in Prader-Willi addressing the unmet needs?
Currently, as there are no approved therapies for Prader-Willi, the administration of growth hormones remains the mainstream pharmaceutical intervention as shown in the comparative landscape of Prader-Willi shown below.
Fast forward to the next 10 years, Mellalta estimates that the Prader-Willi market will grow at least 12 times more than what it is in 2022, thanks to the emergence of some of the novel therapies targeting Hyperphagia, Sleep dysregulation, agitation associated with Prader-Willi, cognitive functions of Prader-Willi patients to name a few.
As per Mellalta, the pharma and the biotech companies along with their key Prader-Willi asset and their MoAs that will play a key role in the Prader-Willi competitive space are:
- Ferring Pharmaceuticals/Levo Therapeutics: Carbetocin (Oxytocin receptor agonists)
- Soleno Therapeutics: DCCR (Potassium channel agonists)
- Aardvark Therapeutics: ARD-101 ((TAS2R) pan-agonist)
- GW Pharmaceuticals/Jazz Pharma: CBDV (Cannabinoid receptor modulators)
- Harmony Biosciences Holdings: Pitolisant (Histamine H3-receptor antagonist)
- Gedeon Richter: RGH-706 (MCHR1 antagonist)
- Saniona: Metoprolol/tesofensine (Beta 1 adrenergic receptor antagonists; Biogenic monoamine uptake inhibitors)
- Biopartners/LG Chem: Eutropin (Growth hormone)
- Harmony Biosciences/ConSynance Therapeutics: HBS-102 (MCHR1 protein inhibitors)
- Neuren Pharmaceuticals: NNZ-2591 (Neuropeptide receptor modulators)
- 15 Other PWS drugs
To know more about the latest Clinical, Commercial and Payer related information on Prader-Willi syndrome, the latest trends, the upcoming key catalyst events, the epidemiology & the market share-related information of the current & emerging therapies in Prader-Willi, request our sample report today—-> PRADER WILLI SYNDROME SAMPLE
