A new treatment is markedly improving the lives of people with Hunter syndrome, a rare genetic disorder that mainly affects males, but funding barriers in many provinces are preventing some families from accessing the costly therapy.
Hunter syndrome involves a shortage of an enzyme that helps break down a substance that interferes with tissue and organ function. Children with Hunter syndrome often go on to experience hearing loss, malformed connective tissue, declining heart function, respiratory problems, stunted growth, sleep apnea and enlargement of the liver and spleen. They tend to have coarse facial features, with a prominent forehead, flattened nose bridge and enlarged tongue. Those more seriously afflicted may not live past their teens. Others live into their 20s and 30s or beyond. There are about 40 known cases in Canada.
The first and only treatment for Hunter syndrome — an enzyme replacement therapy called idursulfase (brand name Elaprase) — was recently approved by Health Canada.
“Besides orthopedic surgery, antibiotics and physiotherapy, we had very little to offer to patients and their families,” says Dr. Serge MelanÃ§on, director of biochemical genetics at the Montreal Hospital for Sick Children. “Now with Elaprase there’s a new era whereby these patients will be improved and their overall life will be better off. They can continue to attend school, find a job and many can have their own families.”
However, some provincial governments won’t cover the cost of the drug — $300,000 to $350,000 per year — on the basis that there are no data to show beneficial effects in the severely affected. In the U.S. and U.K., the drug is available to all Hunter patients regardless of disease severity.
“It’s a human rights issue,” says Simon Ibell, a 29-year-old Toronto resident with Hunter syndrome who participated in a study of Elaprase and whose treatment is funded by the drug manufacturer. “It’s black and white what I’ve seen in younger patients, not having to use wheelchairs, their breathing, overall quality of life.
“Even at my age the treatment had such an impact on my quality of life … improved breathing, decreased organ size, improved joint flexibility.”