EU/3/16/1659 - orphan designation for treatment of inclusion body myositis
arimoclomol citrate
OrphanHuman
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Please note that this product was withdrawn from the Union Register of orphan medicinal products in July 2022 on request of the Sponsor.
On 30 May 2016, orphan designation (EU/3/16/1659) was granted by the European Commission to Orphazyme ApS, Denmark, for arimoclomol citrate for the treatment of inclusion body myositis.
In October 2020, Orphazyme ApS changed name to Orphazyme A/S.
Inclusion body myositis is a condition in which muscle cells become damaged and inflamed, leading to progressive muscle weakness in the legs and arms and difficulty in walking and swallowing. The disease mainly affects people over 50 and is more common in men than in women.
Inclusion body myositis is a long-term debilitating condition due to the development of disabling muscle weakness and problems with swallowing.
At the time of designation, inclusion body myositis affected approximately 0.05 in 10,000 people in the European Union (EU). This was equivalent to a total of around 2,500 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 28), Norway, Iceland and Liechtenstein. This represents a population of 513,700,000 (Eurostat 2016).
At the time of designation, no satisfactory methods were authorised in the EU for the treatment of inclusion body myositis. Patients were often given treatment to suppress the immune system although the benefit was unclear. Supportive measures included physical therapy and exercise, and the use of devices and aids to mobility including motorised wheelchairs.
The mechanisms that lead to the disease are not well understood, but seem to include abnormalities in the way that proteins in muscle cells are folded, leading them to become tangled and clump together inside cells. Arimoclomol is a medicine that stimulates the cell's natural mechanisms for coping with damage, by activating a class of proteins called 'heat shock proteins' in cells that are under stress. Heat shock proteins aid the correct folding of damaged proteins. By activating these proteins in muscle cells that are at risk of damage, the medicine is expected to reduce protein misfolding and so improve muscle weakness and other symptoms of the disease.
The effects of arimoclomol citrate have been evaluated in experimental models.
At the time of submission of the application for orphan designation, clinical trials with the medicine in patients with inclusion body myositis were ongoing.
At the time of submission, arimoclomol citrate was not authorised anywhere in the EU for inclusion body myositis. Orphan designation of the medicine had been granted in the EU and the United States for two other conditions associated with muscle weakness and difficulty moving, called amyotrophic lateral sclerosis and Niemann-Pick disease, type C.
In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 21 April 2016 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.
Orphazyme A/S
Ole Maaløes Vej 3
2200 Copenhagen N
Hovedstaden
Denmark
Tel. +45 39 17 82 72
E-mail: contact@orphazyme.com
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: