EU/3/11/877 - orphan designation for treatment of mucopolysaccharidosis, type IIIA (Sanfilippo A syndrome)
adeno-associated viral vector serotype 9 containing the human sulfamidase gene
OrphanHuman
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On 21 June 2011, orphan designation (EU/3/11/877) was granted by the European Commission to Laboratorios del Dr. Esteve, S.A., Spain, for adeno-associated viral vector serotype 9 containing the human sulfamidase gene for the treatment of mucopolysaccharidosis type IIIA (Sanfilippo A syndrome).
In September 2018, Laboratorios del Dr.Esteve, S.A changed name to Esteve Pharmaceuticals, S.A. The sponsor's address was updated in September 2018.
Mucopolysaccharidosis type IIIA (also known as Sanfilippo A syndrome) is an inherited disease that is caused by the lack of an enzyme (a specialised type of protein) called N-sulfoglucosamine sulfohydrolase. This enzyme is needed to break down a substance in the body called heparan sulphate. Because patients with mucopolysaccharidosis type IIIA cannot break this substance down, it gradually builds up in cells in the body, particularly in the brain, and damages them. This causes a wide range of symptoms, including behavioural problems, learning disabilities, difficulty moving and sleep disturbances. The disease is usually diagnosed in children between two and six years of age.
Mucopolysaccharidosis type IIIA is a seriously debilitating and life-threatening disease because it leads to poor development of language skills and movement, hyperactivity and slow development. The disease usually leads to death during adolescence.
At the time of designation, mucopolysaccharidosis type IIIA affected approximately 0.05 in 10,000 people in the European Union (EU)*. This is equivalent to a total of around 3,000 people, and is below the ceiling for orphan designation, which is 5 people in 10,000. This is based on the information provided by the sponsor and the knowledge of the Committee for Orphan Medicinal Products (COMP).
*Disclaimer: For the purpose of the designation, the number of patients affected by the condition is estimated and assessed on the basis of data from the European Union (EU 27), Norway, Iceland and Liechtenstein. This represents a population of 506,300,000 (Eurostat 2011).
At the time of designation, no satisfactory methods were authorised in the EU for treating mucopolysaccharidosis type IIIA. Bone marrow transplantation had been used to try to slow down the progression of the disease.
Adeno-associated viral vector serotype 9 containing the human sulfamidase gene is a medicine that works by delivering genes into the body. It is made up of a virus that contains the gene for producing the missing enzyme, N-sulfoglucosamine sulfohydrolase. The type of virus used in this medicine (adeno-associated virus) does not cause disease in humans.
When injected into the brain, the virus is expected to carry the gene mainly into the brain cells. These cells are then expected to produce the missing enzyme so that it can break down the accumulated heparan sulphate and help to relieve the symptoms of the disease.
The effects of this medicine have been evaluated in experimental models.
At the time of submission of the application for orphan designation, no clinical trials with the medicine in patients with mucopolysaccharidosis type IIIA had been started.
At the time of submission, this medicine was not authorised anywhere in the EU for mucopolysaccharidosis type IIIA or designated as an orphan medicinal product elsewhere for this condition.
In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 7 April 2011 recommending the granting of this designation.
Designated orphan medicinal products are products that are still under investigation and are considered for orphan designation on the basis of potential activity. An orphan designation is not a marketing authorisation. As a consequence, demonstration of quality, safety and efficacy is necessary before a product can be granted a marketing authorisation.
Esteve Pharmaceuticals, S.A.
The Committee for Orphan Medicinal Products reviews the orphan designation of a product if it is approved for marketing authorisation.
EMA publishes information on orphan medicinal product designation adopted by the Committee for Orphan Medicinal Products (COMP) on the IRIS online platform:
For contact details of patients’ organisations whose activities are targeted at rare diseases, see:
European Organisation for Rare Diseases (EURORDIS), a non-governmental alliance of patient organisations and individuals active in the field of rare diseases.
Orphanet, a database containing information on rare diseases, which includes a directory of patients’ organisations registered in Europe.
The list of medicines that have received an orphan designation in the EU is available on the European Commission's website: