EU/3/16/1740: Orphan designation for the treatment of retinitis pigmentosa

Retinitis pigmentosa is a group of hereditary diseases of the eye that lead to progressive loss of sight. In patients with retinitis pigmentosa, cells in the retina (the light-sensitive surface at the back of the eye) become damaged and eventually die.

Retinitis pigmentosa is a long-term debilitating disease because it causes the patient's sight to get worse, eventually leading to blindness.

At the time of designation, retinitis pigmentosa affected approximately 3.5 in 10,000 people in the European Union (EU). This was equivalent to a total of around 180,000 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 513,700,000 (Eurostat 2016).

At the time of designation, no satisfactory methods were authorised in the EU for treating retinitis pigmentosa. Patients with the condition were given sunglasses to slow down damage to the retina, genetic counselling (discussion of the risks of passing the condition on to children) and general support.

In patients with retinitis pigmentosa, the light-sensitive cells in the retina gradually die. This medicine consists of a virus that has been modified to contain a gene that produces a light-sensitive protein called channelrhodopsin-2 (ChR2). When injected into the eye, the medicine is expected to carry this gene into nerve cells in the retina that are not normally sensitive to light. This would enable these cells to produce ChR2 and thus become responsive to light. This is expected to restore the action of the retina and reduce symptoms of the condition.

The virus used in this medicine (adeno-associated virus) does not cause disease in humans.

The effects of this medicine 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 retinitis pigmentosa were ongoing.

At the time of submission, this medicine was not authorised anywhere in the EU for retinitis pigmentosa. Orphan designation of the medicine had been granted in the United States for retinitis pigmentosa.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 8 September 2016 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.