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Orphan designation

On 24 July 2009, orphan designation (EU/3/09/653) was granted by the European Commission to Alexion Europe SAS, France, for eculizumab for the treatment of atypical haemolytic uraemic syndrome (aHUS).

Eculizumab in treatment of atypical haemolytic uraemic syndrome (aHUS) has been authorised in the EU as Soliris since 24 November 2011.

What is atypical haemolytic uraemic syndrome (aHUS)?

Haemolytic uraemic syndrome (HUS) is a disorder characterised by haemolysis (destruction of red blood cells), thrombocytopenia (a decrease in the number of platelets, components that help the blood to clot), problems with blood clotting and kidney failure. In contrast to most types of HUS, which occur in children after an infection with gut bacteria, atypical HUS (aHUS) affects both children and adults, and is not caused by an infection. More than half of the cases of aHUS are thought to be caused by inherited (inborn) abnormalities of the complement system, a group of proteins in the blood that help the immune system (the body’s natural defence system) to fight infections. In patients with aHUS, the complement system is overactive and damages the cells lining the blood vessels. aHUS can be long term, or can keep coming back (relapsing).

aHUS is a long-lasting and life-threatening disease because of the risk of kidney failure.

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

At the time of designation, aHUS affected approximately 0.1 in 10,000 people in the European Union (EU). This was equivalent to a total of around 5,000 people*, and is below the threshold for orphan designation, which is 5 people in 10,000. This is based on the information provided by the sponsor and 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. At the time of designation, this represented a population of 504,800,000 (Eurostat 2009).

What treatments are available?

At the time of designation, only supportive treatments for patients with aHUS were available. Transfusions of red blood cells and platelets are given as needed. Dialysis (a blood clearance technique) may be needed if the disease progresses to kidney failure. Some patients may receive infusion of plasma or a therapy called plasma exchange although its role in this condition is not completely clear. Some patients may need a kidney transplant.

How is this medicine expected to work?

Eculizumab is a medicine that is already authorised in the EU for the treatment of paroxysmal nocturnal haemoglobinuria (PNH), a rare, life-threatening genetic disease that causes the red blood cells to be broken down too quickly. Eculizumab is a monoclonal antibody (a type of protein) that has been designed to recognise and attach to a specific structure (called an antigen) that is found in the body. Eculizumab has been designed to attach to a protein of the complement system called C5.

By blocking the C5 complement protein, eculizumab is expected to block the activation of the complement system in patients with aHUS, stopping it from attacking the cells lining the blood vessels. This may reduce their destruction and improve the symptoms of the disease.

What is the stage of development of this medicine?

The effects of eculizumab have been evaluated in experimental models.

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

At the time of submission, eculizumab was not authorised anywhere in the EU for aHUS or designated as orphan medicinal product elsewhere for this condition. Orphan designation of eculizumab had been granted in the United States for aHUS.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 4 June 2009 recommending the granting of this designation.

Update: Eculizumab (Soliris) was authorised in the EU on 24 November 2011 for the treatment of patients with atypical haemolytic uraemic syndrome (aHUS).

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 Community) 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.

Key facts

Product details for <p>Eculizumab</p>
Active substanceEculizumab
Medicine NameSoliris
Disease/conditionTreatment of atypical haemolytic uraemic syndrome (aHUS)
Date of decision24/07/2009
Orphan decision numberEU/3/09/653

Review of designation

During its meeting of 5-7 October 2011, the Committee for Orphan Medicinal Products (COMP) reviewed the designation EU/3/09/653 for Soliris (eculizumab) as an orphan medicinal product for the treatment of atypical haemolytic uraemic syndrome. The COMP assessed whether, at the time of addition of a new indication to the marketing authorisation, the medicinal product still met the criteria for orphan designation. The Committee looked at the seriousness and prevalence of the condition, and the existence of other satisfactory methods of treatment. The COMP recommended that the orphan designation of the medicine be maintained1.

1The maintenance of the orphan designation at time of marketing authorisation would, except in specific situations, give an orphan medicinal product 10 years of market exclusivity in the EU. This means that in the 10 years after its authorisation similar products with a comparable therapeutic indication cannot be placed on the market.

Life-threatening or long-term debilitating nature of the condition

The Committee for Medicinal Products for Human Use (CHMP) recommended extending the approved therapeutic indication for Soliris to include the following indication: ‘atypical haemolytic uraemic syndrome (aHUS)’.

This falls within the scope of the product’s designated orphan indication(s), which is: ‘atypical haemolytic uraemic syndrome’.

The COMP concluded that there had been no change in the seriousness of the condition since the orphan designation in 2009. Atypical haemolytic uraemic syndrome remains a condition that is debilitating in the long term or life-threatening, particularly due to kidney failure and the risk of the disease coming back despite a kidney or liver transplant.

Prevalence of the condition

On the basis of the information provided by the sponsor and the knowledge of the COMP, the COMP concluded that the prevalence of atypical haemolytic uraemic syndrome remains below the ceiling for orphan designation, which is 5 people in 10,000. At the time of the review of the orphan designation, the prevalence was still estimated to be approximately 0.1 people in 10,000. This is equivalent to a total of around 5,000 people in the EU.

Existence of other satisfactory methods of treatment

The COMP noted that, at the time of the review of the orphan designation, no satisfactory treatments were authorised in the EU for patients affected by this condition.


Based on the data submitted and the scientific discussion within the COMP, the COMP considered that Soliris still meets the criteria for designation as an orphan medicinal product for the treatment of atypical haemolytic uraemic syndrome and that Soliris should remain in the Community register of orphan medicinal products.

Sponsor’s contact details

Alexion Europe SAS
1-15, avenue Edouard Belin
92500 Rueil-Malmaison
Tel. +33 147323621
Fax +33 147102446

Patients’ organisations

For contact details of patients’ organisations whose activities are targeted at rare diseases, see:

  • Orphanet, a database containing information on rare diseases which includes a directory of patients’ organisations registered in Europe;
  • European Organisation for Rare Diseases (EURORDIS), a non-governmental alliance of patient organisations and individuals active in the field of rare diseases.