Media Release: 27 June 2011
Australian researchers have done a promising pilot study on a small group of people with the harrowing genetic disorder known as ‘Prader-Willi Syndrome’, using a drug already prescribed for some patients with Type 2 diabetes.
Roughly one in 25,000 babies are born with Prader-Willi Syndrome, condemned to develop voracious, insatiable, appetites for life. They grow into obese adults with cardiovascular problems and an average lifespan of roughly 35 years.
Eight people with Prader-Willi Syndrome participated in the recent study, along with 11 obese people matched for age, weight and gender. Participants attended on two separate occasions, each time receiving a meal along with an injection of either saline solution or the drug exenatide. Unaware of which injection they had been given, participants were asked to rate how hungry or full they felt during and after the meal, and to report on any side effects up to 24 hours after.
A group of researchers from Sydney’s Garvan Institute of Medical Research, including Drs Alexander Viardot and Lisa Sze, Professor Lesley Campbell and Louise Purtell, found that people with Prader-Willi Syndrome experienced some significant fullness when given exenatide before food, but had no real fullness when given the placebo instead. In addition, the Prader-Willi group experienced no major side effects from the drug, whereas all but two of the obese-only group experienced bloating, nausea or vomiting. These results are published in the Journal of Clinical Endocrinology and Metabolism, now online.
Professor Campbell, believes the results are sufficiently compelling to merit further, more extensive trials. “The good thing about this study is that people with Prader-Willi Syndrome took a drug that is already in use, they appeared to benefit, and they didn’t suffer side effects,” she said.
“Without further testing, we can’t yet recommend that exenatide be prescribed for these people, unless they also happen to have Type 2 diabetes which is the recommended usage.”
“We are hoping that drug companies will support further trials, even though this is a relatively rare illness.”
“Prader-Willi Syndrome causes such an inordinate amount of suffering for patients and their families that the stress far exceeds the social cost suggested by its low prevalence.”
“It says a lot that our pilot study was funded largely by donations – mostly from affected families.”
Notes to Editors
There are currently around 300 people under the age of 18 with Prader-Willi Syndrome in Australia. In addition to severe lack of appetite control with marked obesity and early cardiovascular complications, Prader-Willi sufferers often have sleep and respiratory problems. They also have a very high pain threshold and no fever, sometimes leading to undiagnosed problems like pneumonia or appendicitis. Cognitive delay and behavioural problems cause difficulties with food behaviour, such as stealing food or gorging, and require supervision.