Why a weekly injection could be the key to Britain’s battle with obesity
A drug called Wegovy is being prepared for a high-street roll-out as well as NHS prescriptions in severe cases – and expectations are high.
In the fight against the flab, there have been many false dawns. “On the surface,” says Simon Cork, senior lecturer in physiology at Anglia Ruskin University, “obesity would seem to be a simple condition to treat: reduce calorie intake and increase calorie expenditure to reduce body mass.”
It hasn’t proved as easy as that. In the past 150 years, agricultural and industrial revolutions have – in rich countries at least – made calories ever cheaper and more available. As a result, people have got heavier and heavier. Today, around two-thirds of Britons are too big, up from about half only 30 years ago. Almost a quarter of children joining school aged just four – are now overweight or obese.
A cascading health crisis has ensued, with fatter people more prone to Type 2 diabetes, cardiovascular disease, and some cancers, placing an ever-greater burden on the NHS. Diabetes alone costs the NHS more than £10 billion a year, with almost one in 20 GP prescriptions for diabetes treatment. And while pharma companies have scrambled to develop an anti-obesity drug, the results have not been good.
“It turns out that weight control has many dimensions,” says Sir Stephen O’Rahilly, professor of clinical biochemistry and medicine at the University of Cambridge. Some are social – like the promotion of cheap, sugary foods. Some are physiological, wired into our bodies. Together, their effect has ensured that the obesity trend has proved incredibly hard to reverse.
Until, it seems, today. For now, there’s Wegovy – which will soon be available for prescription in high street chemists – as long as you can afford the £80 or so monthly cost, and don’t mind self-administering a weekly injection. “As somebody who’s been studying the biology of obesity for decades, it’s been a long journey,” says O’Rahilly. There have, he says, been weight control drugs before. But the safe ones have proved ineffective and the effective ones have proved unsafe, even life-threatening. In trials, Wegovy has been different.
The drug, which is produced by the Danish pharmaceutical company Novo Nordisk, is essentially a modified version of a naturally-occurring hormone, GLP-1, which is made in the gut and signals the sensation of “fullness” to the brain after a meal. There are similar drugs in circulation, including Ozempic, which is licensed for diabetes, and Saxenda, which is licensed for weight loss. They all slow gut emptying slightly, improve insulin sensitivity and reduce hunger.
Elon Musk has used Wegovy to lose weight, while Kim Kardashian is believed to have used a drug containing the same substance, semaglutide, to fit into Marilyn Monroe’s dress for the Met Ball. Jeremy Clarkson says he has had “tremendous” results from Ozempic. “It dulls your appetite,” he has said. “You can look at a Sunday roast, with gravy and beef and perfect Yorkshire puddings, and you think, ‘I’ll just have a stick of celery instead. And maybe just the one bottle of wine, rather than three.’”
“Finally we seem to have got a route to the treatment of obesity,” says O’Rahilly. Given the impact of the Western world’s obesity epidemic – the cost, the health implications, the stigma and misery – the ramifications are huge. “The armoury [of drugs] has been very poor,” says Cork. “To have something that shows very substantial weight loss is hugely exciting.”
The hormone in Wegovy, GLP-1, is part of our internal “wiring” – appetite regulation which, according to Prof O’Rahilly, “detects how much energy we have stored and how much we’ve just eaten, so we don’t fluctuate from Kate Moss to Luciano Pavarotti.” Genetic variation means that “in some people, the system works extremely well, keeping weight under tight control. In others, it works less well. And there are some people where it doesn’t work at all.”
Some people, then, become obese because they have a far stronger biological drive to eat than others. Not only that, but such drives become stronger still after dieting, making it hard to keep the weight off.
Weekly injections of Wegovy have the effect of suppressing appetite in precisely those whose “wiring” has frayed. In a 15-month trial, those on the drug lost around two stone more than those not taking it, amounting on average to more than 10 per cent of body weight. As they lost weight, blood tests showed their risk of cardiovascular disease and diabetes also shrank.
Critically, because Wegovy is based on a natural hormone, it is claimed by its proponents as being largely safe. This could prove vital, because those who start taking it may find themselves on it for life. “Once you stop taking the drug the body weight will go back up,” says Cork. For some, Wegovy may become the new statin.
That’s not to say there are no side effects to consider. Mild ones can include nausea and stomach upset, but these seem to diminish over time. But there are more serious potential longer-term risks too. Gallstones are one. Then there is pancreatitis. “There are risks with Wegovy, notably to the pancreas,” says Tom Sanders, professor emeritus of nutrition and dietetics at King’s College London. “My concern is that if this drug is rolled out as a magic bullet for the masses there will be some nasty side effects.”
“A small number of people will develop pancreatitis which is a life-threatening condition,” says Cork, adding that there remains an obvious question mark for a drug which some may take for decades. “We don’t know the safety profile over 30 or 40 years.”
It is that considering that a year ago led Nice, the body which approves drugs for use in Britain, to issue draft guidance recommending Wegovy’s use in the NHS – but for no more than two years. That is a guideline that Prof O’Rahilly thinks is based on “caution” and “will have to be revisited”, given the need to stay on the drug to keep the weight off.
One year on, however, NHS patients are still waiting, as final approval is dependent on supply guarantees from Novo Nordisk. Boots says it expects to supply Wegovy “in 2023”. Novo itself said in a statement merely that “there is no official launch date but we are working to make Wegovy available in the UK as soon as possible”.
When it does arrive, however, it will only be prescribed on the NHS to the most severe cases – patients referred to multi-disciplinary teams at so-called Tier 3 and 4 specialist weight management services. “And such services are difficult to access at the best of times,” says Cork.
He is surprised at the news of a general high-street roll-out for a treatment which, in the NHS, requires “wrap-around care”.
“I don’t know of any brand new drug like this available through pharmacies without that wrap-around care. I am surprised it’s going to be so freely available,” he says.
But the NHS is likely to benefit if it is widely taken up. According to Jennifer Logue, honorary professor of metabolic medicine at Lancaster University, its current obesity programmes “aim for just five per cent weight loss”.
And Wegovy is only the beginning. “There are lots of drugs in the pipeline,” says Cork. That’s because several hormones regulate appetite. “The drugs in development now mimic multiple hormones and they see an additive effect,” he says. “So the weight loss we see is even greater [than Wegovy].” Eli Lilly’s drug tirzepatide, for example, has produced as much as 22.5 per cent falls in body weight in trials.
Experts believe such appetite suppressants are one-half of a game-changing dual treatment. The other half would be drugs that help people burn off calories faster. “An agent that speeds up metabolism,” says O’Rahilly. So far, he notes “we’ve been much less successful there, but there’s a lot of interest in seeing if you could combine the two.”
Even without metabolism accelerants, Wegovy and similar drugs set to follow it are likely to change the way society views obesity.
“When I was a junior doctor the wards were full of people with uncontrolled blood pressure,” says O’Rahilly. “But we solved the problem with a combination of public health measures – screening, lower salt in food – and also drugs developed to deal with blood pressure. Now our wards aren’t full of strokes due to uncontrolled high blood pressure. So I’m an optimist when it comes to obesity. We just have to put our minds to decent prevention and effective drugs when prevention doesn’t work.”
There is still, adds Cork, a way to go before obesity is – like high blood pressure before it – viewed as a disease to be treated, not a consequence of self-indulgence. He describes the movement on social attitudes toward the obese as “glacially slow”. But he is confident that change will happen.
“Society views obesity as ‘just eat less’,” he says. “But the science says it’s not that easy. People will say: ‘This is just going to promote laziness and unhealthy lifestyles.’ It’s not. Some people are genuinely overweight and obese because that’s how their genetic makeup is determined in today’s environment. Sometimes it can’t be managed without pharmacological intervention. That’s why these drugs are such truly important tools.”
Would you pay for a regular injection if it could help you lose weight?