China is set to publish its first national list of rare diseases to improve diagnoses and speed up drug approvals. Rare illnesses, by definition affecting only a small group of people, are often genetic and costly to treat or control. But they are an increasingly significant segment of the market, and of big pharmaceutical firms’ profits. Global sales of so-called “orphan” drugs to treat rare diseases are set to increase to USD209 billion in the next five years from USD124 billion this year. The niche sector of rare diseases is an important growth driver for companies like Celgene, Bristol-Myers Squibb, Novartis, Johnson & Johnson and Shire. “China, with the largest population in the world, should also have the largest population of rare diseases,” said Peter Fang of Shire, which focuses on rare illnesses and a portfolio of specialist therapies. It sells immunology and haemophilia drugs in China. He estimated that for some rare illnesses, like Fabry disease, caused by the build-up of fat-like substances, fewer than 5% of patients in China are diagnosed. There are an estimated 16 million Chinese with rare diseases, the South China Morning Post reports.