EU/3/13/1205: Orphan designation for the treatment of eosinophilic oesophagitis

Eosinophilic oesophagitis is a disease characterised by inflammation of the oesophagus (the tube that leads from the mouth to the stomach) caused by excess of a type of white blood cell called eosinophils. The main symptoms of the disease are dysphagia (difficulty swallowing), which may lead to food getting stuck in the oesophagus, heartburn and acid regurgitation (acid flowing up into the mouth).

Eosinophilic oesophagitis is a long-term debilitating disease that leads to oesophageal stenosis (narrowing of the oesophagus), which can only be treated with invasive procedures.

At the time of designation, eosinophilic oesophagitis affected less than 5 in 10,000 people in the European Union (EU). This was equivalent to a total of fewer than 256,000 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 28), Norway, Iceland and Liechtenstein. This represents a population of 512,200,000 (Eurostat 2013).

At the time of designation, no satisfactory methods were authorised in the EU for the treatment of eosinophilic oesophagitis. As allergy was thought to be a possible cause of the disease, allergens were excluded from the diet. Oesophageal dilation (widening) was performed in some patients, although it carries the risk of complication such as perforation of the oesophagus.

This medicine is a monoclonal antibody (a type of protein) that has been designed to recognise and attach to interleukin 13 (IL-13). IL-13 is produced at high levels by immune cells in patients with eosinophilic oesophagitis and is involved in attracting eosinophils and inducing inflammation. By attaching to IL-13, the medicine blocks its activity, reducing the number of eosinophils in the oesophagus and relieving inflammation and 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, one clinical trial with this medicine in patients with eosinophilic oesophagitis had been completed and further studies were planned.

At the time of submission, this medicine was not authorised anywhere in the EU for eosinophilic oesophagitis. Orphan designation of the medicine has been granted in the United States for eosinophilic oesophagitis.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 9 October 2013 recommending the granting of this designation.

• 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.