Anti-obesity drug shows promise

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Anti-obesity drug shows promise

Wednesday Feb 15 08:31 AEDT

An anti-obesity drug that turns off the same brain circuits which

trigger the marijuana-induced munchies appears to produce sustained

weight loss among patients who took it in a two-year study,

researchers say.

The report by New York's Columbia University College of Physicians

and Surgeons also said the drug - Sanofi-Aventis SA's Acomplia, or

rimonabant - needs additional study for its long-term effects and

said the research was limited by a high dropout rate. The drug

company funded the study.

The drug is awaiting an approval decision by the US Food and Drug

Administration.

However, there has been speculation that it could become the world's

first blockbuster anti-obesity medicine, with analysts estimating

sales topping $US3 billion ($A4.07 billion) a year.

The report, carried in the Journal of the American Medical

Association, was based on a study involving more than 3,000 patients

that began in 2001 and also involved diet and exercise changes. The

basic findings were released at an American Heart Association

meeting in late 2004.

The final study said the drug plus diet and exercise " promoted

modest but sustained reductions in weight and waist circumference

and favourable changes in cardiometabolic risk factors " such as

cholesterol and triglycerides.

Up to 48 per cent of the patients in the study saw a weight loss of

five per cent or more after one year, depending on the dose of the

drug.

In addition, the report said, the favourable changes in cholesterol

and triglycerides " appeared to be approximately twice that expected

from weight loss alone " , suggesting the drug may have some direct

impact on fat metabolism beyond that caused by slimming down.

" It must be acknowledged that the trial was limited by a high

dropout rate and that long-term effects of the drug require further

study, " the study said.

" Still, our observations collectively suggest that rimonabant may

well represent an innovative approach to the management of multiple

cardiometabolic risk factors, facilitating and maintaining

improvements through weight-loss dependent and independent pathways. "

Rimonabant is the first of a new class of drugs that works by

blocking cannabinoid receptors found in the brain and other body

tissues which stimulate eating in general and are the culprits in

hunger after marijuana use.

In an editorial commenting on the report, experts from the US

National Heart, Lung and Blood Institute sounded a cautionary note,

saying that while the study showed promise the researchers should

have done more follow-up work.

They also said the study had found a higher rate of psychiatric

disorders among those who received the drug compared to those who

got an inert placebo.

Because obesity seems to be a societal problem, attacks against

it " are needed in settings where people live, work and play as well

as in clinical practice. Drug treatments for obesity should be

considered within this broader context and their current role should

be limited pending further evidence, " it said.