EU/3/08/563: Orphan designation for the treatment of traumatic spinal cord injury

Traumatic spinal cord injury is damage to the spinal cord caused by an accident, such as a blow to the back. Injury to the spinal cord can damage and kill the nerve cells that run through the cord and that branch out from it. This can stop the flow of nerve impulses between the brain and the body, resulting in the loss of feeling, paralysis and even death, depending upon the severity of the injury and where it is located.

Traumatic spinal cord injury is life-threatening and chronically debilitating because it can cause paralysis of the arms and legs and reduce life expectancy.

At the time of designation, traumatic spinal cord injury affected approximately 4.2 in 10,000 people in the European Union (EU). This was equivalent to a total of around 211,000 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 27), Norway, Iceland and Liechtenstein. At the time of designation, this represented a population of 502,800,000 (Eurostat 2008).

At the time of submission of the application for orphan drug designation, methylprednisolone (a steroid) was authorised for the treatment of spinal cord injury in some countries in the Community. Methylprednisolone reduces inflammation and pressure on the spinal cord that can happen after it is damaged. Patients with spinal cord injury can also have surgery to reduce the pressure on the spine, but the role of surgery is controversial.

Satisfactory argumentation has been submitted by the sponsor to justify the assumption that recombinant derivative of C3 transferase might be of potential significant benefit for the treatment of traumatic spinal cord injury mainly because it has a new mechanism of action. The assumption will have to be confirmed at the time of marketing authorisation. This will be necessary to maintain the orphan status.

Recombinant derivative of C3 transferase is expected to work by inactivating a group of proteins called 'Rho proteins', which are believed to play a key role in preventing nerve cells from regrowing after they have been damaged. By blocking the activity of Rho proteins, this medicine may allow the nerve cells to repair themselves and regrow their damaged axons (the long processes of nerve cells along which nerve impulses pass). There is also some evidence that the blocking Rho proteins may also prevent the death of damaged nerve cells. Together, these effects may restore the flow of nerve impulses along the spinal cord in patients with traumatic spinal cord injury.

The effects of recombinant derivative of C3 transferase have been evaluated in experimental models.

At the time of submission of the application for orphan designation, clinical trials in patients with traumatic spinal cord injury were ongoing.

Recombinant derivative of C3 transferase was not authorised anywhere worldwide for the treatment of traumatic spinal cord injury, at the time of submission. Orphan designation for recombinant derivative of C3 transferase had been granted in the United States of America for the treatment of acute spinal cord injury.

According to Regulation (EC) No 141/2000 of 16 December 1999, the Committee for Orphan Medicinal Products (COMP) adopted a positive opinion on 11 June 2008 recommending the granting of the above-mentioned designation.

• the seriousness of the condition;
• the existence of alternative methods of diagnosis, prevention or treatment;
• and either the rarity of the condition (affecting not more than five in 10,000 people in the Community) or the 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 the quality, safety and efficacy is necessary before a product can be granted a marketing authorisation.