In trials involving 4, 300 patients, the medicine has been shown to reduce asthma attacks and hospitalisations, and to help improve lung function and quality of life.

BBC: NEWS | Health | New drug for hard-to-treat asthma

Sarah Mullally, Chief Nursing Officer for England, said that currently a specialist asthma nurse treating a child can check their lung function and advise on ways to reduce attacks - but cannot write a prescription for an inhaler.

BBC: Prescribing shake-up planned