U.S. scientists have created an anti-obesity pill that could dramatically reduce weight in a week.
Tests on mice have shown that the drug could decrease body weight by a quarter and their fat content by 42 per cent after seven days.
After a month, the weight of the mice had been reduced by 28 per cent and their fat mass by 63 per cent.
The researchers say further research is needed before the drug is tested on humans. However, they say the results point to a new approach for the treatment of obesity and adult-onset diabetes.
The drug is an artificial hormone made out of glucagon and glucagon-like peptide-1 (GLP-1), natural hormones that regulate glucose metabolism.
These two hormones are similar in structure but they differ in their chemical structure and biological function.
Previous studies have shown they can suppress appetite or cause weight loss by increasing the body's calorie usage.
Dr. Richard DiMarchi and colleagues at Indiana University in the US created the synthetic hormone and carried out the trials on mice.
"Obesity and its associated consequences, including adult-onset diabetes, remain a primary health and economic threat for modern societies," the Telegraph quoted DiMarchi as saying.
At the moment, surgical interventions such as gastric bypass remain the only therapeutic options with the potential for a cure.
Dr. DiMarchi said acute glucagon administration reduces food intake in animals and in humans, and some reports indicate that sustained glucagon receptor activation not only decreases food intake but also promotes weight loss.
"Pharmacological treatment of obesity using single agents has limited efficacy or presents risk for serious adverse effects," he said.
"No single agent has proven to be capable of reducing body weight more than 5 to 10 per cent in the obese population. Combination therapies using multiple drugs simultaneously may represent the preferred pharmaceutical approach to treat obesity, and there is ample precedent for combination therapy in treatment of chronic diseases.
"Here we present results that prove the principle that single molecules can be designed that are capable of simultaneously activating more than one mechanism to safely normalize body weight.
"The present results trigger an array of new questions and the opportunity for further enhancement of the pharmacology.
"First, there is no reason to assume that the fine-tuned combination of these two particular gut hormones in a single molecule represents the only or optimal pharmacological approach to prevent or treat obesity.
"Second, it seems at least theoretically possible to include circulating factors other than gut hormones in an analogous single-molecule co-agonist," he added.
Dr. DiMarchi said that a combination of more than two metabolic control peptides into a single molecule may "provide an even more potent" weapon against obesity.
The findings have been published online in Nature Chemical Biology.