The government is being urged to use its powers to break a deadlock in making a life-extending drug available to people with cystic fibrosis.

Vertex, which makes Orkambi, has refused a £500m offer for the drug over five years - the "largest commitment" the NHS has ever made.

Those affected want other drug firms to be asked to make a cheaper version.

Luis, eight, explains what it is like living with the condition - alongside his mother Christina Walker.

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