Prescription Medicine

Rare Diseases

A rare disease is one that has very low prevalence in a given population. Many are of genetic origin, found during childhood or even early infancy, and can be life threatening or chronically debilitating.

Close to 7,000 rare diseases have been identified worldwide. Definition of rare diseases varies across countries.

  • In the U.S., a rare disease is defined as that which affects <7 per 10,000 (<200,000 people in its population)1
  • In the European Union, a rare disease is defined as that which affects  <5 per 10,0001
  • In Korea, a rare disease is defined as that which affects <4 per 10,000 ( 4<20,000 people in its population) 1
  • In Taiwan, a rare disease is defined as that which effects <1 per 10,0001

Currently, there is no clear definition of rare disease in Hong Kong. Common rare diseases identified in Hong Kong include Mucopolysaccharidosis, Pompe Disease, Fabry Disease, Gaucher Disease and so on. Without access to the right treatment, rare disease can pose serious threat to a patient’s life and immense economic burden and stress to the family.

Reference: 1. http://www.hkard.org/index/about-rare-disease

Aldurazyme (laronidase)

ALDURAZYME® (laronidase) is indicated for patients with Hurler and Hurler-Scheie forms of Mucopolysaccharidosis I (MPS I) and for patients with the Scheie form who have moderate to severe symptoms. The risks and benefits of treating mildly affected patients with the Scheie form have not been established.

Aldurazyme has been shown to improve pulmonary function and walking capacity. Aldurazyme has not been evaluated for effects on the central nervous system manifestations of the disorder.

Reference: Aldurazyme Hong Kong Prescribing Information.

Cerezyme (imiglucerase)

Cerezyme® (imiglucerase) is indicated for long-term enzyme replacement therapy for pediatric and adult patients with a confirmed diagnosis of Type 1 & Type 3 Gaucher disease.

Since its Food and Drug Administration (FDA) approval in 1994, more than 5,600 patients in 90 countries have been treated with Cerezyme. Cerezyme was proven in reducing, relieving and reversing many of the symptoms and risks of Type 1 Gaucher disease.

Reference: Cerezyme Hong Kong Prescribing Information.

Elaprase (idursulfase)

elaprase® (idursulfase) is indicated for patients with Hunter syndrome (Mucopolysaccharidosis II, MPS II). Elaprase has been shown to improve walking capacity in patients 5 years and older.

Reference: Elaprase Hong Kong Prescribing Information.

Fabrazyme (agalsidase beta)

Fabrazyme® is the first specific treatment for Fabry disease, an inherited and often life-threatening disorder characterized by the progressive build-up of a substance known as GL-3 within the cells. As an enzyme replacement therapy (ERT), Fabrazyme replaces the enzyme responsible for lowering GL-3 that is missing or deficient in people with Fabry disease. 

Fabrazyme lowers the amount of a substance called globotriaosylceramide (GL-3), which builds up in cells lining the blood vessels of the kidney and certain other cells. The lowering of GL-3 suggests that Fabrazyme may improve how Fabry disease affects your body; however a relationship of lower GL-3 to specific signs and symptoms of Fabry disease has not been proven.

Reference: Fabrazyme Hong Kong Prescribing Information.

Myozyme (alglucosidase alfa)

Myozyme® (alglucosidase alfa) is indicated for long-term enzyme replacement therapy (ERT) in patients with a confirmed diagnosis of Pompe disease (acid α-glucosidase deficiency).

Myozyme (alglucosidase alfa) is indicated in adults and paediatric patients of all ages.

Reference: Myozyme Hong Kong Prescribing Information.