Technology & Science

Anti-obesity drug no magic bullet

Some doctors in Canada are worried about the side-effects of an anti-obesity drug that is expected to hit the market in the U.S. by spring 2008.

Some doctors in Canada are worried about the side-effects of an anti-obesity drug that is expected to hit the market in the U.S. by spring 2008.

Known in Europe as Acomplia and generically as rimonabant, the drug helps people to lose weight, controls Type 2 diabetes, raises high-density lipoprotein or HDL "good" cholesterol and tells the brain to stop craving food and cigarettes.

The drug has not been approved in North America, although both the U.S. Food and Drug Administration and Health Canada are studying it.
Rimonabant is meant to reduce the risk of diabetes and heart disease, not as a weight-loss aid, says Dr. Josée Dubuc-Lissoir of Sanofi-Aventis in Montreal. ((CBC))

Rimonabant works by blocking cannabinoid receptors in the brain that cause cravings. It also affects other organs such as the liver and pancreas that control blood fats and insulin levels.

It works differently than other anti-obesity drugs but seems to have many of the same side-effects, such as nauseaand diarrhea. People taking rimonabant also have a tendency to get anxious and depressed.

The drug's manufacturer, Sanofi-Aventis, does not want to see the drug used indiscriminately.

"This drug is not aiming for casual weight-loss," said Dr. Josée Dubuc-Lissoir of Sanofi-Aventis in Montreal. "This drug is aiming to decrease the risks of having heart attacks and diabetes."

No major weight loss

In clinical trials, obese people taking rimonabant lost about five per cent of their body weight and maintained the weight loss for a year. If patients stop taking the drug, the pounds come back, just as they would if they stopped dieting and exercising.

Clinical trial participantstook the drug along with diet and exercise, and the combination approach is needed to lose weight and keep it off, saidendocrinologist Dr. Ehud Ur of Dalhousie University in Halifax.
The drug needs to be combined with diet and exercise, says endocrinologist Dr. Ehud Ur of Dalhousie University in Halifax. ((CBC))

"Any notion that this is the magic bullet really needs to be wiped out because I think that's setting us up for inappropriate expectations," Ur cautioned.

Jane Jones of London, England, has lost nine kilograms or 20 pounds in four months on rimonabant. She went on the drug to control her Type 2 diabetes.

"I reckon I'm eating probably nearly a whole meal less during the day because the meals are smaller," said Jones. "It's reduced my intake."

Such weight loss is particularly important for people carrying belly fat, which is linked to an increased risk of heart attacks and strokes.

Some doctors are alarmed at the thought of millions of people worldwide taking a drug for diabetes and obesity indefinitely, but many analysts expect that the drug will earn Sanofi-Aventis $5 billion a year in the U.S. alone.