Special report: New weight-loss drugs experts say are BETTER than Ozempic – from the ‘gym in a jab’, to the injection you take just twice a year

Weight-loss jabs have become a national obsession, it seems.

More than one in five UK adults tried to access weight-loss medications in the past year alone, according to a survey by the National Pharmacy Association. This rises to more than one in three (35 per cent) of those aged under 35.

The soaring demand is because these revolutionary medications can deliver weight loss of up to 15 to 20 per cent of body weight in a year, often without effort – they work by mimicking the hormone GLP-1, reducing appetite (and cravings) and delaying stomach emptying.

Pharmaceutical companies are reaping billions in profits from these drugs – and now old and new players are racing to create even better obesity treatments, many of which work in entirely new ways.

Some of the new generation are more sophisticated variants of the original GLP-1 jabs, such as Wegovy or Mounjaro, but reduce the number of injections from weekly to as little as once every three months.

Pills are also in development to eliminate the need for needles. Other drugs in development work by building muscle while burning fat, or by speeding up metabolism.

‘This is a revolution unfolding in front of our eyes,’ says Carel Le Roux, a professor of metabolic medicine at Ulster University. ‘Next-generation medications will allow even more weight loss in safer ways.’

Alex Miras, a clinical professor of medicine, also at Ulster University, believes that in ten years ‘we will have truly personalised obesity medicine’. He says: ‘Patients will be matched to the drug most likely to work for them based on biology, genetics and personal goals to achieve the best results with the fewest side-effects.’

Scientists hope some of these drugs will have longer-lasting effects on weight than Wegovy or Mounjaro – currently only around 2 to 10 per cent of people keep all their lost weight off if they stop taking GLP-1 drugs.

A University of Oxford study published earlier this year found that people using Wegovy or Mounjaro lost an average of 16kg, but regained an average of almost 10kg in a year if they stopped – and were on target to regain all 16kg in around 20 months.

Some of the new weight-loss drugs in the pipeline seem to lead to better maintenance, without as much weight re-gain. But Professor Le Roux says none of them are a ‘one and done’ treatment. ‘So we need to ask people, “Are you prepared to be on these drugs for the rest of your life?”‘ he says.

Putting people on medication for life is controversial – some experts argue that the drugs should be used in the short-term only, supported by counselling and healthier eating for long-term maintenance of weight loss.

But Professor Le Roux believes that their effects are so transformative on many aspects of health that we should see them as longer-term medications, ‘like blood pressure treatments or statins’. Here, we look at some of the newest weight-loss drugs that could be coming soon…

The ‘gym in a jab’

Today’s main weight-loss wonder drugs, semaglutide (brand names Ozempic, Wegovy) and tirzepatide (Mounjaro), mimic a gut hormone, GLP-1, which is released after eating. Tirzepatide mimics GLP-1 and another gut hormone called GIP.

However, for every 3kg of fat lost, people tend to lose around 1kg of muscle, says Professor Le Roux. Muscle is vital for health, strength and metabolism (including burning calories), so preserving it is key, particularly as we age.

Enter bimagrumab, a new drug that works like weight training in a syringe. Exercise, particularly weight training, helps build muscle – part of the way this happens is that it lowers levels of a protein called myostatin, which regulates muscle growth and fat storage.

Bimagrumab does a similar thing pharmaceutically, helping users lose fat while gaining calorie-burning lean muscle.

A new study, published in June in the journal Endocrine Today, found that patients given bimagrumab alone without any special diet or exercise regimen lost 10.8 per cent of their body weight in 48 weeks – all from fat – while gaining 2.5 per cent lean muscle.

And because bimagrumab, unlike GLP-1 drugs, does not reduce appetite, this happened while users ate around the same number of calories as before.

The results were even more dramatic when bimagrumab was combined with semaglutide. Adding appetite suppression meant people lost 22.1 per cent of body weight, of which 92.8 per cent was fat, compared with 71.8 per cent for semaglutide alone.

Louis Aronne, a professor of metabolic research at Weill Cornell Medicine in the US and part of the research team, said the drug seems especially effective at reducing visceral fat, the type that surrounds abdominal organs and contributes to what he describes as the ‘metabolic mayhem’ associated with obesity, such as insulin resistance (where the cells are unable to take up sugar from the blood, leading to type 2 diabetes) and chronic inflammation.

People on the highest dose of bimagrumab plus semaglutide lost 58 per cent of their visceral fat and their waist size shrank by an average of 9in (22cm). ‘Equivalent to 8.5 holes on a belt,’ said Professor Aronne.

As well as weight loss, people taking the highest dose of bimagrumab plus semaglutide saw levels of a key biomarker of chronic inflammation decrease by 83 per cent after just under a year of treatment. (Chronic inflammation is linked to a host of health problems, from joint pain and low mood to heart disease.)

And the fast weight regain usually seen when people stop taking GLP-1 drugs does not occur with bimagrumab, other research suggests. A study in 2023 by the manufacturer Versanis assessed bimagrumab in patients with obesity and type 2 diabetes. 

This showed a 21.9 per cent reduction in fat mass after 48 weeks of treatment and an increase of lean muscle mass of 4.5 per cent. The same patients were followed for an additional 12 weeks after the last dose and experienced no weight regain. This may be down to the healthier composition of their bodies, the researchers said.

So far, bimagrumab has only been given by intravenous infusion in hospital every few months. Future trials will use injectable versions. Reported side-effects included muscle spasms, diarrhoea and acne in addition to the nausea, constipation and fatigue caused by semaglutide.

When will it be available? 

More trials are under way, with results due in January 2027. These will be followed by larger safety and efficacy trials – so an approval could be a few years away.

2-in-1 ‘surgery’ drug

The company behind Ozempic, Novo Nordisk, has developed new drug CagriSema, which combines semaglutide with a new molecule called cagrilintide. This is a synthetic version of the hormone amylin, produced in the pancreas, which helps us feel full and may play a role in breaking down fat.

In trials, cagrilintide alone led to a 10.8 per cent weight loss over 26 weeks. Combining it with semaglutide magnified the effect, with obese participants losing an average of 22.7 per cent of body weight over 68 weeks. This means CagriSema outperformed Wegovy (14 per cent of body weight lost) and Mounjaro (20 per cent).

Nearly 40 per cent of people on CagriSema experienced a weight loss of at least 25 per cent – with almost a quarter losing 30 per cent or more. This is comparable to stomach-reduction surgery, which varies between 22 and 26 per cent, depending on the type.

Professor Le Roux says early studies showed rats given CagriSema were able to eat 25 per cent more food than rats not on the medication yet lose the same amount of weight.

This is because when rats (or people) diet, the body tries to defend its fat stores by slowing metabolism and reducing the calories burned, he says – as well as ramping up hunger. But cagrilintide persuades the body it should be at a lower weight, so these mechanisms don’t kick in and metabolism doesn’t change.

‘The beauty of this combination is that it targets two distinct satiety-or-fullness pathways in the brain, increasing the effect,’ says Professor Miras, who adds that CagriSema appears similar to semaglutide in terms of potential side-effects.

Studies have also shown that the weekly injection leads to improvements in blood pressure and inflammation similar to those seen with Mounjaro and Wegovy. One potential hurdle, however, is that CagriSema’s two components can’t be dissolved together, requiring them to be manufactured separately and then delivered with a dual-chambered pen, which could prove expensive and inconvenient.

When will it be available? 

Novo Nordisk plans to submit CagriSema for approval in the US early next year, meaning it could be available to patients in late 2026 on private prescription. Approval for NHS use could take longer.

The twice-yearly jab

MariTide is a two-in-one tool for weight loss. Unlike Mounjaro, which activates both GLP-1 and GIP hormone receptors, MariTide blocks GIP while activating GLP-1. (Scientists don’t understand why both activating and blocking GIP leads to similar weight-loss effects, but it does).

Trials show MariTide leads to a loss of around 20 per cent of body weight in a year. But the real game-changer is that the drug is designed to be effective for longer periods than current jabs. In trials, people used it monthly, but there’s evidence the half-life of the drug in the body could be even longer.

Data presented at the American Diabetes Association conference in June showed many participants maintained their weight loss for as long as six months after taking it, raising the prospect of twice-yearly jabs to keep the weight off.

However, around 90 per cent of people experienced nausea and vomiting while on MariTide, with up to a third ditching the drug during the trial as a result. The manufacturer, Amgen, is trialling it at much lower doses to reduce the severity of these side-effects.

When will it be available? 

Trials are ongoing. If results continue to be positive, MariTide could be available from 2028.

‘The next blockbuster’ 

One of the most anticipated new weight-loss drugs is retatrutide, developed by Mounjaro maker Eli Lilly. Known as the ‘triple G’ drug, it targets three receptors: GLP-1, GIP and glucagon.

While GLP-1 and GIP reduce appetite and increase satiety, glucagon increases the calories the body burns at rest. In a trial published in the New England Journal of Medicine in 2023, patients taking the highest dose of retatrutide as a weekly injection lost an average of 24.2 per cent of body weight in 48 weeks. This is even more effective than Novo Nordisk’s CagriSema.

‘This is the next blockbuster drug,’ says Professor Miras. ‘To see this weight loss in under a year without surgery is remarkable. This raises the bar. This is way beyond my wildest dreams.’

Glucagon also helps balance blood sugar levels. Significantly, it reduces liver fat and can even reverse liver scarring caused by fatty liver disease, a condition that affects one in five adults in Britain. Untreated, fatty liver disease can progress to liver cancer. This effect means retatrutide could be used for liver disease alone, says Professor Miras. However, glucagon can be ‘tricky to tolerate and can trigger nausea and vomiting’, he says.

Professor Le Roux adds: ‘Glucagon increases energy expenditure, which is a novel mechanism and trials need to show this is safe.’

When will it be available? 

Retatrutide is in the final phase of clinical trials and may be available in the UK within 18 months.

Pills to cut your appetite in a flash

Hate needles? Well, there’s good news, as weight-loss pills are on the horizon…

Orforglipron

This is a once-daily pill, which, like semaglutide, mimicks GLP-1 – it helps regulate blood sugar levels and reduces appetite.

In final stage trials, reported last week, those taking the drug lost an average of 12.4 per cent of their body weight after 72 weeks.

So far, side-effects are similar to those from other GLP-1 medications: nausea, diarrhoea and constipation.

The pill can be taken at any time of the day. ‘This is a very exciting drug,’ says Professor Le Roux, professor of metabolic medicine at Ulster University.

When will it be available? 

Eli Lilly aims to submit orforglipron for US approval as a weight-loss treatment by the end of 2025. It could become available in the UK in 2026.

Rybelsus

Novo Nordisk is working on a weight-loss version of its daily semaglutide tablet, Rybelsus, currently only licensed for type 2 diabetes. By raising the dose from 14mg to 25mg in trials, participants achieved 13.6 per cent weight loss after 68 weeks.

A trial published earlier this year in the New England Journal of Medicine also found a 14 per cent reduction in risk of heart attacks and strokes. The downsides? Rybelsus must be taken on an empty stomach 30 minutes before food, which may limit appeal. It has similar side-effects to injectable semaglutide, including nausea and vomiting. A plan for a 50mg dose was abandoned due to increased side-effects.

When will it be available? 

A 25mg pill could be available in the US by the end of the year.

Amycretin

Novo Nordisk is developing this drug as both a daily pill and an injection. It mimics GLP-1 and amylin, the pancreatic hormone that regulates glucose, satiety and fat metabolism.

In studies published in July in The Lancet, participants trying the jab lost up to 24 per cent of their body weight in 36 weeks. This is more weight loss at a faster rate than Wegovy.

Early trials have also showed 13.1 per cent weight loss in people who used the daily pill for 12 weeks. Professor Le Roux says: ‘This is an exciting drug with similar but possibly fewer gastrointestinal side-effects than semaglutide and tirzepatide.’

When will it be available? 

It’s still in early trials. Novo Nordisk hopes it could be available before 2030.