EU/3/09/679

Please note that this product was withdrawn from the Community Register of designated orphan medicinal products in November 2012 on request of the sponsor.

On 28 October 2009, orphan designation (EU/3/09/679) was granted by the European Commission to Noscira, S.A., Spain, for 4-benzyl-2-naphtalen-1-yl-1,2,4-thiadiazolidine-3,5-dione for the treatment of progressive supranuclear palsy.

What is progressive supranuclear palsy?

Progressive supranuclear palsy (PSP), which is also known as Steele-Richardson-Olszewski syndrome, is a rare disease that involves the gradual deterioration of parts of the brain. Symptoms include loss of balance with unexplained falls, stiffness, difficulty moving the eyes, particularly up and down, personality changes and dementia (loss of intellectual function). The disease usually starts in people aged over 40 years and gradually gets worse over a number of years.

PSP is a debilitating and life-threatening disease that leads to a progressive inability to move and poor long-term survival.

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

At the time of designation, PSP affected less than 0.7 in 10,000 people in the European Union (EU)*. This is equivalent to a total of around 35,441 people, and is below the threshold for orphan designation, which is 5 people in 10,000. This is based on the information provided by the sponsor and 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. This represents a population of 506,300,000 (Eurostat 2011).

What treatments are available?

At the time of designation, no satisfactory methods were authorised in the EU for the treatment of PSP. Because of their tendency to fall, patients were often offered walking aids, as well as special glasses to help them to look down. Physiotherapy was used to keep the joints flexible. Medicines developed to treat Parkinson’s disease were used in some PSP patients, but their effect was usually temporary and low.

How is this medicine expected to work?

PSP is thought to be caused by proteins called tau sticking together and forming filaments. These filaments build up in brain cells, damaging different areas of the brain. 4-Benzyl-2-naphtalen-1-yl-1,2,4-thiadiazolidine-3,5-dione is expected to work in PSP by blocking an enzyme called glycogen synthase kinase-3β (GSK-3). This enzyme is one of the main factors that make the tau protein become ‘sticky’. By blocking GSK-3, this medicine is expected to reduce the amount of tau protein sticking together, reducing the damage to brain cells.

What is the stage of development of this medicine?

The effects of 4-benzyl-2-naphtalen-1-yl-1,2,4-thiadiazolidine-3,5-dione have been evaluated in experimental models.

At the time of submission of the application for orphan designation, clinical trials in healthy volunteers had finished and trials in patients with PSP were planned.

At the time of submission, 4-benzyl-2-naphtalen-1-yl-1,2,4-thiadiazolidine-3,5-dione was not authorised anywhere in the EU for PSP or designated as 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 2 September 2009 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 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.