EU/3/14/1401: 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 the nerves that run through the cord and branch out from it. This can stop the flow of nerve impulses between the brain and the rest of the body, resulting in the loss of sensation, paralysis and even death, depending on the severity and location of the injury.

Many patients also experience spasticity (or muscle stiffness and spasm) and neuropathic pain (pain due to nerve damage).

Traumatic spinal cord injury is a life-threatening disease that is debilitating in the long term, because it can cause paralysis of the arms and legs, and reduces life expectancy.

At the time of designation, traumatic spinal cord injury affected approximately 3 in 10,000 people in the European Union (EU). This was equivalent to a total of around 153,000 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 511,100,000 (Eurostat 2014).

At the time of designation, methylprednisolone (a steroid) was authorised for the treatment of spinal cord injury in some countries in the EU. Methylprednisolone reduces the inflammation and pressure on the spinal cord that can occur after it is damaged. In addition various medicines were used for the treatment of spasticity (baclofen, dantrolene, diazepam and tizanidine) and for neuropathic pain (amitriptyline, lamotrigine, pregabalin and tramadol). Patients with spinal cord injury also had decompression surgery to reduce the pressure on the spine.

The sponsor has provided sufficient information to show that riluzole might be of significant benefit for patients with traumatic spinal cord injury. Data from clinical studies have shown that riluzole could improve symptoms of spasticity in these patients. This assumption will need to be confirmed at the time of marketing authorisation, in order to maintain the orphan status.

Riluzole is expected to reduce pain and muscle stiffness in patients with traumatic spinal cord injury by blocking sodium channels on the surface of nerve cells. These sodium channels play a role in the activating nerves responsible for spasticity and feeling pain. By blocking them, the medicine helps to reduce these effects. In addition the medicine affects other mechanisms that affect transmission of signals in the nervous system, which may contribute to its action in the condition.

Riluzole is already approved in the EU for the management of amyotrophic lateral sclerosis, a disease of the nervous system.

The effects of riluzole have been evaluated in experimental models.

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

At the time of submission, riluzole was not authorised anywhere in the EU for traumatic spinal cord injury or designated as an orphan medicinal product elsewhere for this condition.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 13 November 2014 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.