The incidence of rare disease defies what the name suggests. Alone, such illnesses are classified as rare if they affect fewer than five in every 10,000 people, but taken in aggregate rare diseases are not in fact rare at all. There are an estimated 30m sufferers in the US, while roughly 6 per cent of the UK population are afflicted with one of 7,000 so-called rare diseases.
It would be fair to assume that developing treatments for these diseases would not be a terribly lucrative market for a pharmaceutical company, and until the 1980s that was certainly the case. But in 1983 a group of organisations in the US made a plea for more to be done to incentivise pharmaceutical companies to invest in rare diseases. And so came the Orphan Drug Act, which granted regulatory and tax incentives to encourage pharmaceutical groups to get developing. The success of the original orphan drug act stateside led to it being adopted in other key markets, including the EU and Japan.
The result has been a huge increase in the development of rare disease treatments. Over the past 30 years, more than 400 medicines representing 447 separate indications have been approved to treat rare diseases, compared with fewer than 10 in the 1970s. The sector is growing at an annual rate of 12 per cent - more than double the growth rate seen in the wider pharmaceuticals market. But issues still exist.