EU/3/19/2135 - orphan designation for treatment of DiGeorge syndrome

Allogeneic cultured postnatal thymus-derived tissue

Overview

On 26 February 2019, orphan designation (EU/3/19/2135) was granted by the European Commission to Enzyvant Therapeutics Ireland Limited, Ireland, for allogeneic cultured postnatal thymus-derived tissue (also known as RVT-802) for the treatment of DiGeorge syndrome.

What is DiGeorge syndrome?

DiGeorge syndrome is a condition characterised by heart defects, a small thymus gland (a gland below the breastbone that helps the T cells that fight infections to develop properly), and underactive parathyroid glands (glands at the base of the neck that produces parathyroid hormones). Signs and symptoms vary widely from patient to patient and include a cleft palate (an opening in the roof of the mouth), heart and breathing problems, learning disabilities, infections, and low blood calcium levels which can result in seizures (fits).

DiGeorge syndrome is a long-term debilitating condition that may be life-threatening particularly because of the heart problems and serious infections.

What is the estimated number of patients affected by the condition?

At the time of designation, DiGeorge syndrome affected approximately 3.7 in 10,000 people in the European Union (EU). This was equivalent to a total of around 192,000 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).

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*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 518,400,000 (Eurostat 2019).

What treatments are available?

At the time of application for orphan designation, there was no satisfactory treatment for DiGeorge syndrome authorised in the EU. Patients generally received supportive treatments to reduce the symptoms, including surgery of the heart and palate, vitamin D and calcium supplements and speech therapy.

How is this medicine expected to work?

The medicine is intended for patients with DiGeorge syndrome who have a non-functional thymus gland and thus very low levels of T cells (a type of white blood cell that fights infections), which makes them prone to infections. The medicine comprises slices of tissue from a donor’s thymus gland. The donor tissue is processed in a laboratory so that it is compatible with the patient’s body and is then inserted into the patient’s body by surgery. This is expected to help patients produce T cells and fight infections.

What is the stage of development of this medicine?

The effects of the 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 DiGeorge syndrome who have a non-functional thymus were ongoing.

At the time of submission, the medicine was not authorised anywhere in the EU for DiGeorge syndrome. Orphan designation of the medicine had been granted in the United States for treatment of patients with complete DiGeorge anomaly.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 24 January 2019 recommending the granting of this designation.

Opinions on orphan medicinal product designations are based on the following three criteria:

• 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.

EU/3/19/2135: Public summary of opinion on orphan designation for allogeneic cultured postnatal thymus-derived tissue for the treatment of DiGeorge syndrome

AdoptedReference Number: EMADOC-628903358-452

Key facts

• Active substance:
  Allogeneic cultured postnatal thymus-derived tissue
• Intended use:
  Treatment of DiGeorge syndrome
• Orphan designation status:
  Positive
• EU designation number:
  EU/3/19/2135
• Date of designation:
  26/02/2019
• Sponsor:

  Myovant Sciences Ireland Limited