Image caption If the seven-year-old boy ate "normally", protein would accumulate in his blood in dangerous concentrations

NHS England has agreed to fund a drug costing about £100 a day for a seven-year-old boy whose condition could cause brain damage, after being told by a judge to reconsider his case.

The child, "S", has a rare condition that means he cannot break down an amino acid, and his autism makes controlling his diet difficult.

NHS England previously said the drug's effectiveness had not been established.

The boy's parents said they were now looking forward to a brighter future.

"S" has phenylketonuria or PKU, and his parents wanted him to take a drug called Kuvan to help him metabolise phenylalanine, an amino acid found in some proteins, which would cost about £100 a day.

If the boy ate normally, protein would accumulate in his blood in dangerous concentrations.

The boy's father said: "It's been a very difficult two years for our whole family while we fought for what we felt was right, and we are now looking forward to a brighter future with our son and for him to enjoy a significantly improved quality of life."

The family's lawyer, Peter Todd, said it was a relief that the funding panel had now finally taken the decision the family had been waiting for.

Image copyright PA Image caption Mrs Justice Andrews quashed the decision at the High Court in London

An NHS consultant who was treating child S, first applied to NHS England for funding for the drug on the grounds that the boy's case was "exceptional".

But NHS England, which takes into account a drug's cost against the benefits it offers when making funding decisions, had refused to pay for Kuvan for him.

'Normal' food

Last month, in a ruling at the High Court, the NHS was ordered to reconsider their decision.

In court, the boy's father described how managing his son's condition had become more difficult over time because the boy had grown more interested in normal foods since going to school and seeing other children eat.

He said the boy would be able to get a proportion of vitamins and minerals from ordinary food if he was prescribed the drug.

Eric Lange, chairman of the national patient charity NSPKU, said he was relieved the NHS had decided to provide Kuvan treatment for the young boy.

"His family should never have been made to fight the NHS through the court to obtain a treatment to keep their child safe.

"Kuvan is an established treatment widely used around the world and it is time that the NHS provided it for other patients in the UK."