Scientists find first long-term obesity drug reduces weight

An experimental obesity drug which only has to be injected once a month helped people lose up to 20 per cent of their body weight.

An experimental obesity drug has shown it can “substantially” reduce weight within a year, offering new hope for people with type-2 diabetes and obesity.

The long-lasting drug maridebart cafraglutide, or MariTide, is the first to be given as a once-a-month jab and in the study of almost 600 adults, it reduced body weight by up to 20 per cent.

The majority of people on the global study were women in their late 40s.

It also included Australian participants from across Victoria, New South Wales and South Australia.

The researchers reported in the New England Journal of Medicine on Tuesday that even after people stopped taking it, weight loss had not plateaued, indicating further weight loss was possible after a year.

The results were also presented at the American Diabetes Association meeting in Chicago.

The researchers said most of the participants on high doses of the drug reported adverse side effects with nausea, vomiting, constipation and headaches the most common, but that these had settled.

The scientists found in the study that the experimental drug reduced body weight by up to 20 per cent over a year.

The international research team included the Head of the Department of Medicine and Head of the School of Clinical Sciences at Monash Health, Monash University Professor Peter Ebeling.

Developed by pharma company Amgen, the drug is described as targeting the same combination of molecules as popular weight loss jabs like Ozempic. It works by activating receptors for appetite and also GLP-1, which is the blood and sugar-reducing hormone made in the small intestine.

GLP-1 also triggers insulin release from the pancreas, which is an essential hormone that allows the body to use food for energy and to lower the amount of glucose (sugar) in the blood.

Lead author of the study Ania Jastreboff is a professor at Yale School of Medicine and director of the Y-Weight Yale Obesity Research Centre. In a statement Professor Jastreboff said the team’s data demonstrated the potential for once monthly or less frequent dosing and “are particularly encouraging as we seek sustainable, long-term treatments for people living with obesity, with and without Type 2 diabetes”.

The drug is the first be given as a once-a-month jab with the results described by scientists in a study as “encouraging”.

Amgen said that the side effects reported in the trial may lead to a slower dosing schedule.

A spokesman said MariTide may also allow for greater durability or reduce the likelihood of weight regain after treatment stops.

Dr Jay Bradner, the company’s executive vice president of Research and Development, said MariTide’s monthly or less frequent dosing has the potential to improve adherence and long-term weight control, providing the opportunity to optimise health outcomes for people living with obesity, Type 2 diabetes and related conditions.”

In a new study later this year Amgen said it will begin its chronic weight management studies of the drug. These will enrol people with atherosclerotic cardiovascular disease, heart failure and obstructive sleep apnoea.