THE family of a six-year-old boy is fighting for a potentially life-changing drug to be made available on the NHS.

Cobey Burdis, from Chester-le-Street, suffers from a rare lifelong condition called phenylketonuria (PKU), where the body cannot break down the amino acid phenylalanine.

He can only eat five grams of protein a day and the only treatment available in the UK is dietary therapy.

It means he has an extremely restrictive and regimented low protein diet, that excludes foods most people take for granted.

Cobey, has two sisters, Rosie and Connie, and desperately wants to be able to eat the same things they do.

His father, Craig, said: “It’s very tough having to say ‘no’ all the time when he asks for foods he is not able to have.

“He is not even able to eat foods such as regular bread and pasta, and has to be supplemented by foods specially manufactured for a low-protein diet.”

Mr Burdis said failure to adhere to the diet can result in severe mental retardation in children, seizures, anxiety and depression, nerve damage and a host of other neurological and executive functioning consequences.

He said Kuvan, a drug produced by BioMarin, works to lower the blood phenylalanine concentrations in those who respond to it, and in some cases has even rendered the restrictive diet unnecessary.

Mr Burdis said: “The PKU diet is so restrictive that most people cannot cope with the rigours and burden of the diet, and struggle to adhere beyond adolescence.

“The systems used by NICE and the NHS to appraise drugs for rare diseases, such as Kuvan, are inadequate, and sufferers of conditions such as PKU have been massively failed by the system.

“We have been let down, and the UK now has one of the poorest standards of care for Phenylketonuria in the whole of Europe.

“With other pharmacological therapies currently going through EU appraisal and coming on the horizon, and the failure of the NHS and government to adopt the use of Kuvan, there is a very real concern that PKU patients in the UK will be left behind the rest of Europe and the world.”

BioMarin holds the patent of Kuvan although the firm did not invent the drug.

A petition started by a small group of patient-led activists asking BioMarin to lower the price of Kuvan has amassed more than 13,000 signatures so far.

The ongoing battle to secure the drug for UK PKU sufferers hit national news headlines recently and last month The Northern Echo reported on the case of another sufferer, seven-year-old Lily-Mae Scott, from Darlington.

Diagnosed through the newborn screening heel prick test, about one in 10,000 babies in the UK are born with PKU

Research by the National Society for Phenylketonuria has found that care standards throughout the UK vary massively.

Kuvan is thought to be available in most other countries across Europe and in many other parts of the world.

A Department of Health and Social Care spokesperson said: “We want all patients to have access to the best medicines at a price the NHS can afford and for many years people have benefitted from new treatments thanks to NICE’s internationally respected methods.

“NICE balances the cost of medicines with their proven clinical benefits to ensure the NHS pays a fair price for the most innovative treatments.”

NICE, the National Institute for Health and Care Excellence, said it had not begun its appraisal of Kuvan to treat PKU.

A spokesman said: "Following a challenge to the decision to review the drug through the NICE technology appraisal programme, we made the exceptional decision to pause the appraisal at this point and ask the topic selection decision making panel to reconsider whether this topic is suitable for the NICE highly specialised technologies or technology appraisal programme.

"After this a formal referral will be required from the Minister to determine the process under which Kuvan will be assessed."