Table 1.
Definitions
| Orphan disease – A disease which has not been ‘adopted’ by the pharmaceutical industry because the small market provides little financial incentive for the private sector to make and market new medications to treat or prevent it. The definition is based on disease prevalence and differs between Europe and the USA |
| European definition. Life-threatening or very serious disease affecting not more than five in 10 000 people in the European Community. This includes tropical diseases which are uncommon in Europe but common elsewhere |
| USA definition. The term ‘rare disease or condition’ means any disease or condition which (a) affects <200 000 persons in the USA, or (b) affects >200 000 persons in the USA and for which there is no reasonable expectation that the cost of developing and making available in the USA a drug for such disease or condition will be recovered from sales in the USA of such drug |
| Ultra-orphan disease – A very rare disease. There is no formal definition but the National Institute of Clinical Excellence uses the term for diseases affecting <1000 people in England and Wales |
| Orphan medicinal product (OMP) – Products for the diagnosis, prevention or treatment of orphan diseases. For OMP designation in Europe there needs to be no satisfactory method of diagnosis, prevention or treatment of the orphan disease in the European Community. Alternatively, the medicinal product must confer a significant benefit compared with the existing diagnostic, preventative or therapeutic products available for the orphan disease |
| USA Orphan Drug Act (1983) and EU Orphan Drug Regulation (2000) — Legislation designed to encourage the development of OMPs. In both territories there is marketing exclusivity which prevents any competitor gaining market access unless superiority is demonstrated. In both territories the regulatory authorities offer assistance in the design of clinical trials; and they waive their normal licensing fees. In the USA (but not the EU) there is also tax relief and the possibility of access to ear-marked research grants. |
| ICER (incremental cost-effectiveness ratio) – The financial cost for each extra unit of health improvement gained by using the intervention |
| QALY (quality-adjusted life year) – A measure of the quantity and quality of life generated by a healthcare intervention. Provides a unit which can be used to compare different interventions |