Scientists in Perth, West Australia will start testing a brand new weight-loss pill in the hope it will not only help them lose weight but also reduce their chance of heart diseases by increasing levels of good cholesterol or HDL.

The hospital trials, as part of an international trials, could prove the weight-loss drug named Rimonabant, developed by the French drugmaker Sanofi Aventis, can cure the condition known as metabolic syndrome, a particularly high risk form of obesity which entails problems controlling cholesterol, insulin and blood pressure.

Gerald Watts, Royal Perth Hospital professor of medicine, who specializes in metabolic disturbances, said the medicine is expected to be approved in Australia within a year and the hospital aimed to enrol 15 to 20 patients as part of the 80 being studied worldwide.

The medications that have been available until now have had toxic issues and some work but have no long-term safety data, so this is a new approach to the controlling of weight gain.

The medicine works by blocking chemical processes in the brain, which results in less appetite and also acts on the liver to help the body burn more fat, but side-effects can include nausea and diarrhea.

Were curious in the mechanics of how this medicine works and the function it could play in obese people who have several risk ingredients for heart conditions, one of which is low HDL cholesterol, or metabolic syndrome, he said.

Professor Watts said the bottom line is to help people lose weight, which then reduces their chance of other sicknesses such as diabetes. It means that people end up eating less and burning more fat so its a very powerful instrument for targeting obesity, but beyond that its also an powerful instrument for curing smoking and even alcohol mis-use, he said.

The hospital is enlisting men and women aged between 35 and 65 who are overweight or obese with a waist perimeter of more than 40inches in men and 88cm in women and have high triglycerides with low HDL cholesterol. They will be put on a diet to lose 5 per cent of their body weight and some will be selected to continue on the Rimonabant trials.

In trials that have been conducted, the gains that have been seen in terms of increasing HDL cholesterol could not be explained by the weight loss alone, so it clearly has a direct effect on the HDL cholesterol.