Rare Diseases

Rarediseases 1030

A disease is defined as rare when its prevalence, that is the number of cases present at a given time in a given population, does not exceed a certain threshold. In the European Union this threshold is set at 0.05% of the population, namely 1 case per 2,000 inhabitants. Other countries such as the USA adopt different parameters: here a disease is considered rare when it does not exceed the 0.08% threshold.

However, the low prevalence does not mean that overall there are few people with a rare disease.
When talking about these diseases, we can think that it is something that affects only a few unfortunate people. But if we look around most of us know someone directly or indirectly affected by such conditions. In fact, about 300 million people around the world are suffering from over 6,000 rare disease

A important challenge from a scientific perspective and above all with a strong social impact to which Angelini Pharma has decided to commit. In the field of rare diseases, the Company aims to develop innovative health solutions to help patients and their families.

As long as families and people suffering from rare diseases need effective treatments, Angelini Pharma will work hard to contribute in finding the most appropriate solutions.

Rare diseases Key Facts

Rare diseases

  • Epidemiology

    It is estimated that between 3.5 and 5.9%1 of the world's population is affected by rare diseases, equal to

    • 263-446 million people globally
    • 18-30 million in the European Union alone

    Almost all (98%) of rare patients are affected by a small group (390) of high prevalence diseases. On the other hand, the remaining 2% are affected by low prevalence diseases, which we could call "ultra-rare".2

  • Diagnosis and Disease Management

    The management of rare genetic diseases present some important and very critical issues: first of all the challenge of diagnosis which may be difficult and late because these conditions are unknown under may aspects, moreover for most of such diseases no specific treatments are available, the specialized Hospital Centres are sparse and the conditions generate a strong emotional impact on patients and families.

    People suffering from rare diseases are therefore more vulnerable with regards to psychological, social, economic and cultural aspects.

  • Treatment

    These diseases have in common their complexity and difficulty in a timely and correct diagnosis and only 5% of them have an available resolving therapy5. In these cases, early diagnosis is essential to ensure the success of treatments and prevent possible complications.


  1. Estimating cumulative point prevalence of rare diseases: analysis of the Orphanet database, European Journal of Human Genetics. Available online: - Source:
  2. Estimating cumulative point prevalence of rare diseases: analysis of the Orphanet database, European Journal of Human Genetics. Available online - Source:
  3. Estimating cumulative point prevalence of rare diseases: analysis of the Orphanet database, European Journal of Human Genetics. Available online: Available online - Source:
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Angelman syndrome

  • Definition

    Angelman Syndrome is a rare genetic and neurological disorder characterized by

    • Severe developmental delays and learning disabilities
    • Absence or near absence of speech
    • Inability to coordinate voluntary movements (ataxia), tremulousness with jerky movements of the arms and legs
    • A distinctive behavioral pattern characterized by a happy disposition and unprovoked episodes of laughter and smiling

    Other clinical signs include

    • Happy appearance
    • Hyperactivity without aggression
    • Low level of attention
    • Excitability
    • Sleep disorders associated with reduced need for sleep
    • High sensitivity to heat and attraction to water
  • Epidemiology

    • It’s a rare disease that affects almost 60,000 people worldwide
    • Its prevalence is estimated between 1/10,000 and 1/20,0004
  • Diagnosis

    • Children between 6 and 12 months of age begin to show feeding problems and developmental delay
    • Epileptic seizures may appear around 2-3 years of age5
  • Transmission

    It is caused by several genetic mechanisms, such as

    • Chromosome duplication (60-75% of cases)
    • Uniparental dysomy (2-5%)
    • An imprinting defect (2-5%)
    • The mutation of a gene along the arm of chromosome 15 (10%).

    The genetic defect was not identified in 5-26% of patients6


  1. Angelman Sindrome, Orpha.net website Available online:
  2. Angelman Sindrome, Orpha.net website Available online
  3. Angelman Sindrome, Orpha.net website Available online: Available online
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