EU/3/12/1095 - orphan designation for treatment of mucopolysaccharidosis type IIIB (Sanfilippo B syndrome)

adeno-associated viral vector serotype 9 containing the human N-acetylglucosaminidase-alpha gene

Overview

Please note that this product was withdrawn from the Union Register of orphan medicinal products in January 2025 on request of the Sponsor.

On 24 January 2013, orphan designation (EU/3/13/1095) was granted by the European Commission to Laboratorios del Dr. Esteve S.A., Spain, for adeno-associated viral vector serotype 9 containing the human N-acetylglucosaminidase-alpha gene for the treatment of mucopolysaccharidosis type IIIB (Sanfilippo B syndrome).

For a list of the administrative updates to this public summary of opinion please refer to the PDF document below.

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.

What is mucopolysaccharidosis type IIIB (Sanfilippo B syndrome)?

Mucopolysaccharidosis type IIIB (also known as Sanfilippo B syndrome) is an inherited disease that is caused by the lack of an enzyme called alpha-N-acetylglucosaminidase. This enzyme is needed to break down a substance in the body called heparan sulphate. Because patients with mucopolysaccharidosis type IIIB 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.

Mucopolysaccharidosis type IIIB typically starts in children between three and six years of age. It 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 youth.

What is the estimated number of patients affected by the condition?

At the time of designation, mucopolysaccharidosis type IIIB affected approximately 0.009 in 10,000 people in the European Union (EU). This was equivalent to a total of around 450 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).

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*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 509,000,000 (Eurostat 2013).

What treatments are available?

At the time of designation, no satisfactory methods were authorised in the EU for treating mucopolysaccharidosis type IIIB.

How is this medicine expected to work?

Adeno-associated virus serotype-9 vector containing the human alpha-N-acetylglucosaminidase 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 alpha-N-acetylglucosaminidase, the enzyme missing in patients with mucopolysaccharidosis type IIIB. The virus is expected to carry the gene into cells, enabling the cells to produce the missing enzyme for breaking down the accumulated heparan sulphate. This is expected to help relieve the symptoms of the disease.

The type of virus used in this medicine (adeno-associated virus) does not cause disease in humans.

What is the stage of development of this medicine?

At the time of submission of the application for orphan designation, the evaluation of the effects of the medicine in experimental models was ongoing.

At the time of submission of the application for orphan designation, no clinical trials with the medicine in patients with mucopolysaccharidosis type IIIB had been started.

At the time of submission, the medicine was not authorised anywhere in the EU for mucopolysaccharidosis type IIIB 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 6 December 2012 recommending the granting of this designation.

Opinions on orphan medicinal product designations are based on the following three criteria

• the seriousness of the condition;
• the existence of alternative methods of diagnosis, prevention or treatment;
• either the rarity of the condition (affecting not more than 5 in 10,000 people in the EU) or insufficient returns on investment.

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.

EU/3/12/1095: Public summary of opinion on orphan designation: Adeno-associated viral vector serotype 9 containing the human N-acetylglucosaminidase-alpha gene for the treatment of mucopolysaccharidosis type IIIB (Sanfil...

Adopted Reference Number: EMA/COMP/805822/2012 Rev. 1

Key facts

• Active substance:
  adeno-associated viral vector serotype 9 containing the human N-acetylglucosaminidase-alpha gene
• Intended use:
  Treatment of mucopolysaccharidosis type IIIB (Sanfilippo B syndrome)
• Orphan designation status:
  Withdrawn
• EU designation number:
  EU/3/12/1095
• Date of designation:
  24/01/2013
• Sponsor:

  Esteve Pharmaceuticals, S.A.;

Review of designation

The Committee for Orphan Medicinal Products reviews the orphan designation of a product if it is approved for marketing authorisation.