Weight loss jabs like Wegovy combat several diverse conditions, from heart attacks to cancer, and the explanation may be that they stop inflammation
Wegovy and Mounjaro have been taking the world by storm for their unprecedented ability to help people shed weight.
New studies suggest that the injections stop heart attacks and strokes, not just through weight loss, but also by an anti-inflammatory effect.
The same explanation may be behind why they are better than expected at preventing cancer, experts said at the European Congress on Obesity, in Malaga, this week.
Now, interest is growing in whether the jabs could be used to reduce inflammation in many different medical conditions, even in people who are not extremely overweight.
Killing bacteria
Inflammation was first understood by doctors as helpful immune response. We may notice it happening if the skin around a cut becomes red and sore.
In this form of inflammation, the immune system is sending cells to the break in the skin, to kill any bacteria that get into the body and to promote healing. The first cells to reach the injury release chemical messengers called cytokines that recruit more immune cells and increase blood flow – which is why the skin looks red.
But prolonged low-level inflammation is involved in many disease processes. For example, heart attacks can be caused when fatty deposits called plaques inside arteries break open and release deadly clots. The plaques are more likely to rupture when they have more inflammatory immune cells and cytokines inside.
This is why the latest results for Wegovy and heart disease have piqued doctors’ interest.
Wegovy (also called semaglutide, or Ozempic when used for diabetes) and similar medicines were developed to mimic an appetite suppressing hormone called GLP-1.
The new results come from a randomised trial comparing Wegovy injections to placebo versions in nearly 18,000 people who had previously had a heart attack or stroke. Over the next three years, 20 per cent fewer people taking Wegovy had a second such incident.
The latest research, which is a deeper analysis of those results, found that the difference in heart attack and strokes arose very early on in the trial, and could even be seen in the first three months.
That was too early for the protection to be happening just from weight loss and suggests it must be a direct effect of the medicine, said Professor Donna Ryan, an obesity specialist at Pennington Biomedical Research Center, who was involved in the trial. “It preceded any clinically meaningful changes in body weight,” she said.
US doctors sometimes do blood tests for a protein called CRP in people with heart disease, with higher levels indicating more inflammation.
In the trial, doctors found that CRP levels quickly fell in those taking Wegovy – suggesting its anti-inflammatory effect was a possible explanation for the rapid protection against heart attacks and strokes, said Professor Ryan. “We are finding that GLP-1 agonists are wonderful anti-inflammatory agents.”
Anti-cancer agents
In a different study, similar weight loss drugs to Wegovy were found to give greater protection against cancer than would be expected from their effect on weight alone – and this also could be because they block inflammation.
Being overweight is known to raise the risk of some types of tumours, including breast and colon cancer.
When people have weight loss surgery, like a gastric bypass, they generally lose 30 per cent of their weight, and their rate of cancer also falls by 30-40 per cent.
The new study compared 3,000 pairs of people who had either surgery or took one of the earlier versions of the GLP-1 mimics, who were tracked for about seven years.
Wegovy needs to be injected weekly (Photo: Iuliia Burmistrova/Getty Images/Moment RF)
Those having the weekly injections lost about 14 per cent of their weight, compared with 31 per cent for the surgery patients. Despite the difference in weight loss, both groups had a similar rate of obesity-related cancers, said Professor Dror Dicker, an obesity specialist at Hasharon Hospital in Israel, who was involved in the research. “It’s something beyond weight loss,” he said. “Most probably anti-inflammatory effects.”
Inflammation is thought to contribute to cancer by causing mutations that let cells multiply out of control and by boosting growth of blood vessels, which bring oxygen and nutrients to tumours.
There is also early research suggesting weight loss drugs may have protective effects in various other conditions where inflammation plays a role, including Alzheimer’s disease and depression, said Dr Tim Blackstock, an analyst at pharmaceutical intelligence company, Citeline. “This potentially opens up new indications for the drugs.”
Once semaglutide’s patents expire, due to happen in the next decade, the injections will become cheaper, and more people are likely to start taking them, predicted Dr Blackstock.
For any medicine, patients need to weigh up the risks and benefits with their doctors, but the GLP-1 mimics may become a drug that most people past a certain age should consider, in the same way that statins are now routinely used, said Dr Blackstock.
“It’s quite early days in terms of where this might lead, but it’s definitely promising,” he said.