Maintenance evidence at a glance
Three Phase 3 trials (large human trials with thousands of participants) have tested what happens after a GLP-1 medication is stopped or switched.
| Trial |
Weight loss-phase medication |
Maintenance arm result |
Stopped or placebo arm result |
| STEP 4 (semaglutide) |
Wegovy 2.4 mg for 20 weeks (~10.6% loss) |
Continued Wegovy: a further 7.9% loss over 48 weeks2 |
Switched to placebo: 6.9% regain over 48 weeks2 |
| SURMOUNT-4 (tirzepatide) |
Mounjaro up to 15 mg for 36 weeks (~20.9% loss) |
Continued Mounjaro: a further 5.5% loss; 25.3% total at 88 weeks3 |
Switched to placebo: 14% regain; 9.9% total at 88 weeks3 |
| ATTAIN-MAINTAIN, Mounjaro group |
Mounjaro during SURMOUNT-5 (72 weeks) |
Switched to oral orforglipron: 74.7% of weight loss kept over 52 weeks1 |
Switched to placebo: 49.2% of weight loss kept over 52 weeks1 |
| ATTAIN-MAINTAIN, Wegovy group |
Wegovy during SURMOUNT-5 (72 weeks) |
Switched to oral orforglipron: 79.3% of weight loss kept over 52 weeks1 |
Switched to placebo: 37.6% of weight loss kept over 52 weeks1 |
All four arms also included diet and physical activity support, which contributed to the results above.
Why weight regain happens when you stop an injection
On a GLP-1 medication, the drug keeps hunger and food noise lower. It does this by slowing digestion and communicating with parts of the brain that control appetite.
When we come off the medication, we no longer have that support in lowering appetite. If the habits needed to keep hunger lower naturally haven’t been developed, appetite is likely to return.
Appetite also tends to return faster when the medication is stopped suddenly, rather than tapered down gradually.
STEP 4, published in JAMA in 2021, took 803 adults who’d lost an average of 10.6% of their body weight on weekly semaglutide over 20 weeks, then randomised them either to continue semaglutide or switch to placebo for a further 48 weeks.2
People who kept taking Wegovy lost a further 7.9% on average, while those who switched to placebo regained 6.9%, giving a difference of 14.8 percentage points by week 68.2
SURMOUNT-4 did the same experiment with Mounjaro. After 36 weeks on tirzepatide, 670 participants who’d lost around 20.9% of their body weight were randomised to continue or switch to placebo for 52 weeks.3
Those who continued Mounjaro lost a further 5.5%, bringing the total weight loss to 25.3%. Those who switched to the placebo regained an average of 14%, ending with a total weight loss of 9.9%.3
A later analysis of SURMOUNT-4 found that the improvements in blood pressure, cholesterol, and blood sugar control depended on how much weight people kept off. Participants who regained at least a quarter of their lost weight lost most of those improvements.4
The finding isn’t that GLP-1 medications cause regain when they’re stopped. But these results do show that when you stop taking the medication suddenly, and you don’t develop the habits you need to naturally maintain lower hunger levels, then weight regain is likely.
What the ATTAIN-MAINTAIN trial found
ATTAIN-MAINTAIN is the first Phase 3 trial to test whether an oral GLP-1 medication can be used to support weight maintenance after weight loss is achieved with GLP-1 injections.1
Researchers recruited 376 people who’d completed SURMOUNT-5, a trial that directly compared injectable Mounjaro with injectable Wegovy over 72 weeks.
In SURMOUNT-5, the Mounjaro group lost an average of 20.2% of their body weight and the Wegovy group 13.7%.12
ATTAIN-MAINTAIN investigated whether a daily oral medication could support weight maintenance over the next 52 weeks.1
Participants were randomised in a 3:2 ratio to either oral orforglipron at the maximum tolerated dose or placebo. The trial used 24 mg and 36 mg capsules, and the 36 mg capsule delivers the same dose as the 17.2 mg Foundayo tablet now approved in the UK.
Everyone continued the lifestyle support they’d received during SURMOUNT-5, including diet and physical activity guidance.1
The results were reported separately for the two groups, based on which injection people had been on:
- Mounjaro switchers (205 participants): orforglipron maintained an average of 74.7% of the weight loss from SURMOUNT-5, compared with 49.2% on placebo. That’s a treatment difference of 25.5 percentage points. People on orforglipron regained around 5 kg over the year; people on placebo regained substantially more.1
- Wegovy switchers (171 participants): orforglipron maintained, on average, 79.3% of the weight loss observed in SURMOUNT-5, compared with 37.6% on placebo. That’s a treatment difference of around 42 percentage points. People on orforglipron regained roughly 1 kg over the year.1
Among Mounjaro switchers, 43.7% of those on orforglipron maintained at least 80% of their original weight loss, compared with 16.4% on placebo.
The Wegovy figures were 55.0% on orforglipron and 6.9% on placebo.1 Improvements in cholesterol, blood pressure, and blood sugar control from SURMOUNT-5 were largely preserved.1
Orforglipron isn’t as potent for active weight loss as injectable Mounjaro.
The earlier ATTAIN-1 trial in adults with obesity or overweight resulted in an average weight loss of approximately 11.2% at 72 weeks, below the 20.2% observed with Mounjaro in SURMOUNT-5.
ATTAIN-MAINTAIN suggests maintaining weight loss may not need a medication as potent as the one that produced the initial loss, especially with sustained habit support.
What this means if you’re coming off Mounjaro or Wegovy
ATTAIN-MAINTAIN adds a new option for those who’ve reached their weight-loss goals with Mounjaro or Wegovy.
The existing routes are continuing the injection, stepping down to a lower dose, or coming off and maintaining weight loss without medication support.
Switching to a daily oral medication is now another route, too.
The Wegovy pill is on sale in the UK, and Foundayo is approved and available to pre-order ahead of going on sale. Of the two, only Foundayo has been tested for holding weight loss after switching off an injection.1
Most people on the maintenance arm of ATTAIN-MAINTAIN still regained some weight (around 5 kg for Mounjaro switchers, around 1 kg for Wegovy switchers), so the realistic goal is to keep most of the loss rather than expecting to keep it all off.1
In ATTAIN-MAINTAIN, everyone on orforglipron continued the diet and physical activity coaching they’d received during SURMOUNT-5.
So the results suggest that combining oral medication with lifestyle changes led to weight maintenance, not the medications on their own.
If you stop the injection and don’t continue to focus on maintaining healthy habits, you have less chance of maintaining weight loss in the long term.
For more on the practical questions around tapering and timing on Mounjaro specifically, see our guide on how long you can stay on Mounjaro, and on Wegovy, how long you can stay on Wegovy.
Maintaining muscle mass through the transition
People who’ve lost 15 to 25% of their body weight with injectable Mounjaro or Wegovy may have lost some of that weight as muscle and other lean tissue.
Maintaining muscle mass becomes more important during the transition off the injection, when appetite returns, and protein intake can drop.
Three things help maintain muscle mass during weight loss and through the transition into maintenance.
The first is eating enough overall, including fat and carbohydrate as well as protein and fibre, because the body needs enough energy to function and to maintain muscle.
The second is eating about 1.2 to 1.6 grams of protein per kg of body weight per day, which is roughly a serving the size of the palm of your hand at each meal. For someone weighing 90 kg, that’s around 110 to 145 grams of protein daily.
The third is resistance training a couple of times a week. That can be bodyweight exercises (squats, lunges, press-ups), resistance bands, dumbbells, or weight machines.
During the transition off an injection, the medication’s effect on hunger and food noise fades. As that happens, the habits built during treatment are what keep hunger manageable.
Could the Wegovy pill be used for maintenance?
There’s no clinical reason why the Wegovy pill couldn’t be used for weight-loss maintenance, but no trial has tested it that way.
The Wegovy pill (oral semaglutide 25 mg) is on sale in the UK. See our Wegovy pill guide for more on the medication itself.
OASIS 4, published in the New England Journal of Medicine in 2025, tested oral semaglutide 25 mg against placebo for 64 weeks in 307 adults, with the pill arm losing 13.6% of body weight against 2.2% on placebo.5
OASIS 4 enrolled people who hadn’t lost weight yet and measured how much they lost over 64 weeks. It didn’t take people who had already lost weight on an injection and test whether the pill kept it off, which is what ATTAIN-MAINTAIN did.
ATTAIN-MAINTAIN is the only Phase 3 maintenance trial of an oral GLP-1 medication to date.
A prescriber could consider the Wegovy pill as a step-down from injectable Wegovy on practical grounds, since both contain semaglutide. But the dosing and timing differ, and there are no published trials testing the Wegovy pill for maintenance.
UK availability and timing
The MHRA approved Foundayo (orforglipron) on 10th August 2026, making the UK the first country in Europe to license it.11
The licence covers weight loss and weight maintenance in adults with a BMI of 30 or above, or 27 to 30 with at least one weight-related condition. That’s the same wording as Wegovy’s licence, so using a GLP-1 for maintenance is within licensed use rather than something new.8,11
Foundayo isn’t on sale yet, because a newly approved medication takes a few weeks to reach pharmacies and providers. The Wegovy pill followed the same pattern, with approval on 11 June 2026 and sales starting around three and a half weeks later.10
You can pre-order Foundayo through Second Nature now if you meet the eligibility criteria, and your medication is dispatched once it goes on sale.
Foundayo isn’t available on the NHS. NICE would need to complete a health technology assessment first, and there’s no confirmed timeline for that decision.11
UK prices haven’t been announced, and each provider will set its own. In the U.S., self-pay pricing launched at around $149 a month for the lowest dose and $349 a month for the highest.6
The Wegovy pill was approved by the MHRA on 11 June 2026 and is available through weight-loss programmes such as Second Nature and online pharmacies.10
Alongside the two tablets, the existing UK maintenance options are continuing injectable Mounjaro, continuing injectable Wegovy (now available at both 2.4 mg and the higher 7.2 mg dose, which was MHRA-approved in January 2026), or stepping down to a lower maintenance dose of either injection.
The role of habits in long-term maintenance
Habits and lifestyle are the foundation of maintaining weight loss regardless of the medication.
ATTAIN-MAINTAIN tested orforglipron alongside continued diet and physical activity coaching, so the weight maintenance in the trials is a result of medication and lifestyle change combined, not either on its own.
The medication lowers hunger and quietens food noise, which makes eating less feel easier. This provides us with the opportunity to develop a healthier lifestyle.
Think of GLP-1 medications a bit like stabilisers on a bike. They give you the opportunity to learn healthier habits, and in the long term, those habits will help maintain a healthy weight, with or without the medication.
The Second Nature programme is built around this principle. We pair medication with structured habit support that supports weight loss maintenance when the medication’s effect reduces, whether that’s maintaining at a lower dose, switching medications, or coming off entirely.
Frequently asked questions
What is ATTAIN-MAINTAIN?
ATTAIN-MAINTAIN is a 52-week Phase 3 trial that tested whether oral orforglipron (Foundayo) could maintain weight loss achieved during a previous injectable GLP-1 trial.1
It’s the first Phase 3 trial of an oral GLP-1 specifically for maintenance after stopping injections.
Can a pill maintain weight loss as well as an injection?
In ATTAIN-MAINTAIN, oral orforglipron preserved most of the weight loss participants had achieved on Mounjaro or Wegovy: 74.7 to 79.3% on average, compared with 37.6 to 49.2% on placebo.1
All participants received lifestyle support throughout the trial.
Is Foundayo available in the UK?
Foundayo is approved in the UK but not yet on sale. The MHRA approved it on 10th August 2026, and it’s expected to reach providers in the coming weeks.11
You can pre-order it through Second Nature now if you meet the eligibility criteria. It isn’t available on the NHS, which would need a NICE recommendation first.
Is the Wegovy pill approved for maintenance after stopping the injection?
No. The Wegovy pill (oral semaglutide 25 mg) has been tested as a treatment for weight loss in the OASIS 4 trial.5
It hasn’t been tested specifically as a maintenance medication after stopping injectable Wegovy or Mounjaro.
Can I just step down to a lower dose of Mounjaro or Wegovy instead?
Yes. Wegovy is available at 2.4 mg and 7.2 mg, with the higher dose MHRA-approved in January 2026.
Mounjaro is available in doses from 2.5 mg to 15 mg, so stepping down to a lower dose is also possible.
The right choice depends on how you’re tolerating the medication, the dose you reached, and what your prescriber recommends.
Why would someone switch from Mounjaro to a pill for maintenance?
The main reasons people consider switching are convenience (a daily tablet rather than a weekly injection) and potentially cost.
Foundayo is the only tablet tested for holding weight loss after switching off an injection.1 The Wegovy pill is on sale now but hasn’t been tested that way.
Will I regain all my weight if I stop Mounjaro or Wegovy?
Not necessarily. In SURMOUNT-4, people who stopped Mounjaro without continuing any maintenance medication regained about 14% on average, but maintained about 10% of their weight loss compared with their starting weight.3
How much regain happens depends largely on the habits built during treatment and on whether maintenance support continues.
How long does Mounjaro or Wegovy stay in the system after stopping?
Tirzepatide has a half-life of around 5 days and semaglutide around 7 days, so both typically clear the body fully over 4 to 6 weeks after the last dose.7,8
Appetite usually returns gradually over this window rather than suddenly. However, this will depend on the habits you’ve developed prior to coming off the medication.
What’s the role of habits if a maintenance pill is available?
Habits remain the foundation. ATTAIN-MAINTAIN itself paired the maintenance pill with ongoing lifestyle support, and orforglipron is less potent than the injections people were stepping down from.1
The medication lowers hunger while you take it. The habits are what keep it manageable once you stop.
Is there a maintenance trial for the Wegovy pill underway?
No published or announced maintenance trial of oral semaglutide 25 mg specifically after stopping an injection has been identified at the time of writing. That leaves a gap in the evidence now that both tablets are licensed in the UK.
Can I switch directly from Mounjaro to Foundayo in the UK?
That’s a clinical decision for a prescriber, and Foundayo needs to be on sale before a pharmacy can dispense it.
ATTAIN-MAINTAIN supports switching from an injection to oral orforglipron for maintenance, and maintenance is within Foundayo’s licensed use, but the right dose and timing for an individual would be set by the clinician.1,11
Take home message
ATTAIN-MAINTAIN is the first Phase 3 trial to show that a daily oral GLP-1 medication can preserve most of the weight loss achieved with injectable Mounjaro or Wegovy when paired with ongoing lifestyle support.1
For those living in the UK, the practical options today are to continue the injection, step down to a lower injectable dose (including Wegovy 7.2 mg, MHRA-approved in January 2026), switch to the Wegovy pill, which is on sale now, or pre-order Foundayo, which was approved in August 2026 and is expected on sale in the coming weeks.
Of those, only Foundayo has been tested for weight maintenance after switching from an injection.1,2,3
Second Nature’s published research shows that members on semaglutide combined with structured habit-change coaching achieved an average weight loss of 19.1% at 12 months, with 77.7% achieving at least 10% weight loss.9
Our programme is designed around the balanced plate model (half vegetables, a quarter protein, a quarter complex carbohydrates, plus a serving of fat) and focuses on building habits that support long-term weight loss after the medication ends or the dose is reduced.
Second Nature's Mounjaro and Wegovy programmes
Second Nature provides Mounjaro or Wegovy as part of our Mounjaro and Wegovy weight-loss programmes.
Why choose Second Nature over other medication providers, assuming you're eligible?
Because peace of mind matters.
We've had the privilege of working with the NHS for over eight years, helping people across the UK take meaningful steps toward a healthier, happier life.
Our programmes are designed to meet people where they are, whether that means support with weight loss through compassionate one-to-one health coaching, or access to the latest weight-loss medications (like Mounjaro and Wegovy) delivered alongside expert care from a multidisciplinary team of doctors, psychologists, dietitians, and personal trainers.
At the heart of everything we do is a simple belief: real, lasting change comes from building better habits, not relying on quick fixes. We're here to support that change every step of the way.
With over a decade of experience, thousands of lives changed, and a long-standing record of delivering programmes used by the NHS, we believe we're the UK's most trusted weight-loss programme.
We hope to offer you something invaluable: peace of mind, and the support you need to take that first step.
