Tutorial - Ethics of children in clinical trials

Rare disease

There is no single definition of rare disease. Diseases which are rare in some countries may be common in others. In Europe a disease is defined as rare when it affects less than 1 in 2,000 citizens and in the USA less than 1 in 1,500. There are thought to be around 5,000 to 7,000 different types of rare disease which together affect between 6-8% of the population. In Europe this is about 30 million people.

Rare diseases are often:

• chronic, progressive, degenerative, and life-threatening
• disabling: the quality of life of patients is often compromised by the lack or loss of autonomy and the burden on patients and their families can be high
• without an existing, effective cure

Rare disease patients face common problems:

• lack of access to correct diagnosis
• delay in diagnosis
• lack of quality information on the disease
• lack of scientific knowledge of the disease
• heavy social consequences for patients
• lack of appropriate quality healthcare
• inequities and difficulties in access to treatment and care

The case of Duchenne muscular dystrophy (DMD)

For the purposes of this tutorial we will use the example of DMD which is a rare disease but also one of the most common genetic disorders affecting children and young adults. DMD usually affects boys and there are approximately 26,000 people in the world with this disorder.

DMD is a severe, muscle wasting condition with onset in early childhood. The progressive muscle weakness and wasting leads to those affected becoming wheelchair bound by their early teens and increasingly dependent on care as they get older. There is no cure. DMD generally leads to death by the early twenties, although in some countries men are living longer. The social and emotional costs and burden for patients and their families are very high.