EU/3/05/292: Orphan designation for the hearing loss (acute acoustic trauma, sudden deafness and surgery induced acoustic trauma)

Hearing loss can begin suddenly (acutely) or slowly and persisting over a long period of time (chronic). Acute sensorineural hearing loss is a sudden hearing loss resulting from damage to cells in the cochlea, the organ of hearing, which is located behind the eardrum. Although it is not always possible to identify the cause of this type of hearing loss, known causes of injury are exposure to noise (acoustic trauma) or a direct damage to the hearing system (for instance secondary to surgery).

Some patients recover fully while others will remain with a hearing loss that can vary in intensity. This may result in impaired interpersonal communication, learning difficulties, impaired ability to work, irritability, etc. and is therefore considered as seriously debilitating.

At the time of designation, acute sensorineural hearing loss (acute acoustic trauma, sudden deafness and surgery induced acoustic trauma) affected approximately 3.7 in 10,000 people in the European Union (EU). This is equivalent to a total of around 173,000 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 25), Norway, Iceland and Liechtenstein. At the time of designation, this represented a population of 466,600,000 (Eurostat 2005).

Several products mostly aimed to improve the blood circulation and oxygenation of the inner ear were authorised for the condition in some countries in the Community at the time of submission of the application for orphan drug designation.

Satisfactory argumentation has been submitted by the sponsor to justify the assumption that AM-111 might be of potential significant benefit for the treatment of acute sensorineural hearing loss mainly because it might improve the long-term outcome of the patients. This assumption will have to be confirmed at the time of marketing authorisation. This will be necessary to maintain orphan status.

The damage caused to the inner ear results in the death of those cells responsible for the transmission of sounds. Different biochemical mechanisms lead to the death of those cells. Blocking (inhibiting) these mechanisms would prevent further cell death and thus the size of the damage could be limited. AM-111 is a peptide that inhibits (blocks) one of these biochemical mechanisms. It is therefore expected to interrupt the destruction of the cells and thus might limit the intensity of the hearing loss.

At the time of submission of the application for orphan designation, no clinical trials in patients with acute sensorineural hearing loss (acute acoustic trauma, sudden deafness and surgery induced acoustic trauma) were initiated.
AM-111 was not authorised anywhere worldwide for acute sensorineural hearing loss (acute acoustic trauma, sudden deafness and surgery induced acoustic trauma) or designated as orphan medicinal product elsewhere for this condition, at the time of submission.

According to Regulation (EC) No 141/2000 of 16 December 1999, the Committee for Orphan Medicinal Products (COMP) adopted on 12 May 2005 a positive opinion recommending the grant of the above-mentioned 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 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.