Pressure is mounting on the NHS to widen the use of a “wonder” drug that could help hundreds of thousands of severe asthma sufferers.

Currently, most of the 250,000 UK patients who suffer from severe allergic asthma are prescribed powerful oral steroids.

They cause patients to gain significant amounts of weight and eventually develop diabetes, cataracts and glaucoma. About half go on to suffer from osteoporosis and other suffer from depression, anxiety and even growth retardation. That has to be worth reducing.”