EU/3/14/1370

On 19 November 2014, orphan designation (EU/3/14/1370) was granted by the European Commission to Novartis Europharm Limited, United Kingdom, for siponimod for the treatment of polymyositis.

What is polymyositis?

Polymyositis is an inflammatory disease of the muscles, characterised by muscle weakness, difficultly moving and tiredness. In addition to skeletal muscles (the muscles used for movement), the muscles of the oesophagus (food pipe), the respiratory system and the heart are sometimes affected, leading to difficulties in eating and breathing.

Polymyositis is an auto-immune disease. This means that it is caused by the body’s immune system attacking its own tissues. The damage and inflammation are mainly due to immune system cells called T cells and macrophages. The reason why the immune system acts in this way is not known.

Polymyositis is a life-threatening and long-term debilitating condition particularly due to muscle weakness, lung and heart problems.

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

At the time of designation, polymyositis affected approximately 0.4 in 10,000 people in the European Union (EU). This was equivalent to a total of around 20,000 people*, and is below the ceiling for orphan designation, which is 5 people in 10,000. This isbased 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 28), Norway, Iceland and Liechtenstein. This represents a population of 511,100,000 (Eurostat 2014).

What treatments are available?

At the time of designation, prednisolone was authorised for the condition in some EU countries.

The sponsor has provided sufficient information to show that siponimod might be of significant benefit for patients with polymyositis because early studies have shown improvement in muscle function in patients for whom other treatments have stopped working. This assumption will need to be confirmed at the time of marketing authorisation, in order to maintain the orphan status.

How is this medicine expected to work?

Siponimod is expected to work by attaching to some receptors called sphingosine-1-phosphate receptors (i.e. S1P1 and S1P5), which are involved in the movement of immune cells around the body. By attaching to these receptors, siponimod is expected to reduce the movement of these cells from the lymph nodes into the muscles where they can attack the tissues. This is expected to ease the symptoms of the disease.

What is the stage of development of this medicine?

The effects of siponimod have been evaluated in experimental models.

At the time of submission of the application for orphan designation, clinical trials with siponimod in patients with polymyositis were ongoing.

At the time of submission, siponimod was not authorised anywhere in the EU for polymyositis. Orphan designation of siponimod had been granted in the United States for this condition.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 9 October 2014 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.

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