Hunter Syndrome was in the headlines last year when Andrew Wragg, 40, a former SAS soldier, was driven to despair by the decline of his son Jacob, 10, and smothered him with a pillow. The father, from Worthing, was cleared of murder and given a suspended sentence for manslaughter with diminished responsibility.

The fatal syndrome, suffered almost exclusively by boys, is caused by a defective enzyme that is unable to break down complex sugars produced as waste products in the body. These compounds, called mucopolysaccharides, accumulate in the tissues and organs and cause worsening physical and mental health problems.

The new drug, Elaprase, developed by Shire Pharmaceuticals, has been approved in the US and is expected to be licensed in Europe by the end of the year. Given by infusion, it improves breathing and movement. Parents of some Hunter children say it has transformed them.

But it will cost at least £100,000 per child per year, and as much as £300,000 for older, heavier patients who need bigger doses. Although the number of Hunter children in the UK is small — no more than about 100 — the cost of providing it for all of them could well be prohibitive.

A patients’ group has been lobbying ministers to confirm that the drug will be funded under a special scheme for children with rare diseases. Christine Lavery, chief executive of The Society for Mucopolysaccharide Diseases (SMD), said: “Funding for treatments for rare diseases similar to Hunter Syndrome is due to end at Christmas. We expect that to be extended. But there has been no promise that the DoH will fund the new drug for Hunter Syndrome.

“All our questions and requests for clarification of the position have met with a lack of response, which leads us to fear the worst.”

Although not a cure the drug, which replaces the missing enzyme, may allow affected children to lead near-normal lives if the condition is picked up early. Dr Ed Wraith, a consultant at the Royal Manchester Children’s Hospital, said: “With this disease, there is damage to the heart, liver, brain and other organs which invariably leads to death well before the age of 20. The treatment is a major breakthrough and it would be a tragedy if the Department of Health didn’t provide the money.”

The Department of Health said: “No decision has yet been made on whether this expensive drug will be funded.”

The same is likely to be the case north of the Border, where the Scottish Medicines Consortium has refused a related drug for a girl with a similar condition.

Bob Wragg, 64, grandfather of Jacob, said: “Thank God they have found a treatment at last.” His wife, Anne, a nurse, said: “A lot of people just don’t understand the torment that Andrew went through caring for Jacob and seeing him get worse and worse.”

An adult sufferer of the syndrome, Colin Arrowsmith, 26, from Newcastle, has been receiving Elaprase weekly as part of a trial since February 2004.

He had already defied doctors’ predictions that he would be dead by his early teens and until five years ago was able to live independently. He worked in the mailroom of an electricity company but was forced to give it up because his hips began to crumble. This forced him into a wheelchair and made him more reliant on his parents.

His mother, Barbara, said: “He was picking up lots of infections and his liver and spleen were very large. Since he began the weekly infusions his general health is better and his liver and spleen are no longer swollen. He has a lot more energy.

“The treatment won’t reverse the damage done but we’ve been told that it should prevent further damage.”

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