What is an orphan drug ?
The so-called 'orphan drugs' are intended to treat diseases so rare that sponsors are reluctant to develop them under usual marketing conditions.
The process from the discovery of a new molecule to its marketing is long (10 years in average), expensive (several tens of millions of euros) and very uncertain (among ten molecules tested, only one may have a therapeutic effect). Developing a drug intended to treat a rare disease does not allow the recovery of the capital invested for its research.
Orphan drugs may be defined as :
Drugs that are not developed by the pharmaceutical industry for economic reasons but which respond to public health need.
Actually, the indications of a drug may also be considered as ' orphan ' since a substance may be used in the treatment of a frequent disease but may not have been developed for another, more rare indication.
In fact, three cases may arise :
- Products intended to treat rare diseases :
These products are developed to treat patients suffering from very serious diseases for which no treatment, or at least a satisfactory one, has so far been available. These diseases affect only a small proportion of the population (less than one person per 2,000 in Europe), most often at birth or in infancy. The number of rare diseases for which no treatment is currently available is estimated to be between 4,000 and 5,000 world-wide. Twenty-five to 30 million people are reported to be affected by these diseases in Europe.
- Products withdrawn from the market for economic or therapeutic reasons :
For example, thalidomide widely much used as a hypnotic drug some years ago and was then withdrawn from the market when its high teratogenic (triggering fetal malformations) risk was discovered. However this drug showed very interesting analgesic proprieties in diseases such as leprosy or lupus erythematosus. They are diseases for which no satisfactory treatment has been available.
- Products that have not been developed :
- either because they are derived from a research process that cannot be patented ;
- or because they concern important markets which are, however, not creditworthy (see the text Orphan drugs for Third-World countries).
Patients affected by rare diseases have to be informed about scientific and therapeutic progress. They have the same rights to care as any other patient. In order to stimulate research and development in the sector of orphan drugs, the authorities have implemented incentives for health and biotechnology industries. It started as early as 1983 in the United States with the adoption of the Orphan Drug Act, then in Japan and in Australia in 1993 and 1997. Europe followed in 1999 by implementing a common EU policy on orphan drugs.