EU/3/18/2014: Orphan designation for the treatment of Stargardt's disease

Stargardt's disease is a hereditary disorder of the eye that leads to progressive loss of sight. Stargardt's disease is caused by abnormalities in a gene called ABCA4. The ABCA4 gene is responsible for the production of a protein called ABCR that regulates the transport of substances in and out of some cells in the retina (the light-sensitive surface at the back of the eye). In patients with Stargardt's disease, ABCR does not work properly. This causes deposits known as lipofuscins made of fats and proteins to build up inside the retina cells, which become damaged and eventually die.

Stargardt's disease is a long-term debilitating disease because the patient's sight becomes progressively worse and eventually leads to blindness.

At the time of designation, Stargardt's disease affected approximately 1.3 in 10,000 people in the European Union (EU). This was equivalent to a total of around 67,000 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 517,400,000 (Eurostat 2018).

At the time of designation, no satisfactory methods were authorised in the EU for the treatment of Stargardt's disease.

The lipofuscin deposits in the retina of patients with Stargardt's disease are made up of substances called bisretinoids. The process that forms bisretinoids in the eye involves attachment of vitamin A (retinol) to a substance called retinol-binding protein 4 (RBP4).

This medicine is expected to work by blocking RBP4. This is expected to reduce the formation of bisretinoids in the eye and so decrease damage caused by lipofuscin deposits.

The effects of the medicine have been evaluated in experimental models.

At the time of submission of the application for orphan designation, no clinical trials with the medicine in patients with Stargardt's disease had been started.

At the time of submission, the medicine was not authorised anywhere in the EU for Stargardt's disease. Orphan designation of the medicine had been granted in the United States for the condition.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 19 April 2018 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.