EU/3/17/1882: Orphan designation for the treatment of growth hormone deficiency

Growth hormone deficiency is a condition where the patient lacks a sufficient amount of growth hormone, which is normally secreted by the pituitary gland (at the base of the brain). Growth hormone promotes growth during childhood and adolescence, and also acts on the way the body handles proteins, fat and carbohydrates (sugars). The condition can be caused by a genetic mutation (change) or other factors such as trauma and inflammation, or it may have no known cause. It can affect people of any age. In childhood, the main signs include failure to grow normally and impaired development of bones and skeletal muscle. In adulthood, the condition can affect the heart, muscles and bones, alter metabolism and cause psychological symptoms such as anxiety and depression.

Growth-hormone deficiency is a long-term debilitating condition that includes decreased bone mass, bone fractures and psychological symptoms. The disease can be life-threatening due to the risk of problems with the heart and blood circulation.

At the time of designation, growth hormone deficiency affected approximately 4.6 in 10,000 people in the European Union (EU). This was equivalent to a total of around 237,000 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 515,700,000 (Eurostat 2017).

At the time of designation, medicines containing recombinant human growth hormone were authorised in the EU to treat growth hormone deficiency. These were given to patients by daily injection.

The sponsor has provided sufficient information to show that the medicine might be of significant benefit for patients with growth hormone deficiency. Early studies show that the medicine, which can be given by mouth and works in a different way to authorised medicines, can improve growth rate in children with the condition. This assumption will need to be confirmed at the time of marketing authorisation, in order to maintain the orphan status.

The release of growth hormone in the body is regulated by a complex system of hormones. Ibutamoren mesilate acts similarly to GHRP6, a regulating hormone which stimulates the body to produce more growth hormone. Taking the medicine is therefore expected to increase the body's natural production of growth hormone, and so help overcome the effects of this condition.

The effects of ibutamoren mesilate 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 growth hormone deficiency were ongoing.

At the time of submission, ibutamoren mesilate was not authorised anywhere in the EU for growth hormone deficiency 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 12 May 2017 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.