Foundayo for Weight Maintenance: What the Evidence Shows

• Explains what the MHRA licence actually covers, including maintenance
• Honest about the gap between the licence and evidence for switching treatments
• Covers what national quality standards say about support after treatment stops
• Online consultation with UK registered prescribers to review whether maintenance treatment is appropriate

Foundayo is licensed for weight maintenance, not only for losing weight. When the MHRA approved orforglipron on 10 August 2026, the indication covered weight loss and weight maintenance in adults with a BMI of 30 or more, or between 27 and 30 with weight related health conditions, alongside a reduced calorie diet and increased physical activity.

That wording matters, because maintenance is where weight management treatment usually comes apart. Losing weight and keeping it off are different problems with different biology behind them, and the evidence on what happens after treatment stops is uncomfortable reading for anyone hoping a course of treatment resolves things permanently.

Key things to know

• The MHRA licence for orforglipron covers weight maintenance as well as weight loss.
• Weight regain after stopping weight management medication is a well documented pattern rather than a personal failure.
• Clinical trial evidence now includes maintenance after previous treatment with tirzepatide or semaglutide.
• Phase 3 evidence for orforglipron covers 72 weeks, with average weight loss ranging from around 7.5% to 11.2% depending on the dose studied.
• No published trial addresses switching from an injectable treatment to Foundayo specifically for maintenance.
• Dose in a maintenance phase is a prescriber decision, and no maintenance schedule should be followed from an article.
• Treatment continuing long term is reviewed regularly rather than assumed.

Is Foundayo licensed for weight maintenance?

Yes. The MHRA approval covers weight loss and weight maintenance in adults meeting the criteria, used alongside a reduced calorie diet and increased physical activity. Maintenance is written into the indication rather than being an off licence use someone has decided makes sense.

That is a meaningful distinction. A medicine used for something outside its licence is being used on a prescriber's individual judgement, with different considerations around evidence and responsibility. Maintenance use here sits inside the licence, which means it was part of what the regulator assessed.

The diet and activity requirement is not decorative. It appears in the licence because the trial results were achieved with that support in place, which makes it part of the treatment rather than an optional accompaniment.

Why maintenance is a different problem

Keeping weight off is harder than losing it, and the reason is physiological rather than motivational. After weight loss, the body adjusts in ways that favour regain: appetite signalling changes, and energy expenditure falls to a level lower than would be expected for the new body weight. Those adjustments persist rather than resolving after a few months.

This is the part people are rarely told before starting treatment, and not knowing it turns a predictable biological response into a source of personal blame. Regaining weight after stopping is not evidence that you did it wrong. It is what the body is set up to do.

The practical implication is that maintenance needs a plan of its own, decided before treatment ends rather than after regain has started. That is the reasoning behind how national quality standards approach it.

What national quality standards say about stopping

Updated national quality standards on managing overweight and obesity, published in August 2025, set out that people stopping weight management medication should receive support for at least a year afterwards. Specifically, providers should offer regular feedback over that period, support to develop new routines that help maintain weight, and an action plan to use if weight does begin to return.

The principle behind it is stated plainly in that guidance: successful weight management does not end when medication stops. That is a useful sentence to hold onto, because it reframes the end of treatment as a transition requiring its own care rather than a finish line.

What happens when treatment stops

Weight regain after stopping weight management medication is well documented across this family of treatments. Reviews of the evidence consistently find that weight tends to return after treatment ends, and that the return begins relatively soon rather than after a long stable period. This pattern occurs because the body responds to weight loss with biological adjustments such as changes in appetite signalling and a decrease in energy expenditure, which can contribute to weight gain and excess weight if not managed properly.

In the phase 3 ATTAIN trials, orforglipron produced clinically meaningful weight loss over 72 weeks when used alongside diet and physical activity. In ATTAIN-1, average weight change at week 72 was −7.8%, −9.3% and −12.4% with the 6 mg, 12 mg and 36 mg doses respectively, compared with −0.9% with placebo. Results in ATTAIN-2, which included people with type 2 diabetes, ranged from −5.5% to −10.5% across the studied doses.

These results describe weight loss during treatment. They should not be interpreted as showing what will happen to an individual after treatment is stopped.

What the evidence does not show

The evidence on maintenance has moved forward, but it still has important limits.

ATTAIN-MAINTAIN is particularly relevant because it examined orforglipron after previous treatment with injectable tirzepatide or semaglutide. Participants were randomised to orforglipron or placebo after reaching a weight plateau. The trial found that orforglipron helped participants retain more of their previous weight reduction than placebo at week 52. However, there was no group continuing the injectable treatment, so the study cannot establish that switching to orforglipron is equivalent to continuing the original medicine.

Longer-term real-world evidence will still be needed as the medicine is used more widely.

Results from different weight-management medicines should not be compared directly unless they come from a head-to-head trial. Study populations, doses, treatment durations and outcome measures can differ substantially.

The switching question deserves emphasis because it is one of the practical issues people may ask about. Moving from an injectable treatment to a daily tablet may be considered by a prescriber, and there is now clinical trial evidence specifically examining orforglipron after previous treatment with tirzepatide or semaglutide.

The ATTAIN-MAINTAIN trial found that participants receiving orforglipron retained more of their previous weight reduction over 52 weeks than those receiving placebo. However, the trial did not compare orforglipron directly with continued injectable treatment, so it does not establish that switching produces the same outcome as staying on the original medicine.

How to read a licence against a trial

These two things get conflated and they answer different questions. A licence states what a regulator has assessed a medicine as appropriate for, based on the evidence submitted. A trial reports what happened to a particular group of people over a particular period under particular conditions.

A licence covering maintenance tells you the regulator was satisfied the evidence supported that use. It does not tell you the medicine was tested in every situation where maintenance comes up, including after a different treatment, after a break, or after weight has already started returning. Those are gaps in the evidence rather than gaps in the licence, and they are filled by clinical judgement rather than by reading the indication more carefully.

Foundayo after an injectable treatment

Switching between weight management treatments is a clinical decision and needs prescriber involvement, for practical reasons rather than procedural ones.

Treatments in this family are not interchangeable unit for unit. They differ in how they are taken, how they build up and clear from the body, and how treatment is started. When taking Foundayo, it is used once daily, with or without food. Foundayo differs from injectable GLP-1-based treatments in how it is administered and dosed. Moving between them involves planning, particularly around the timing between the last dose of one and the first of another, and that timing is specific to the treatments involved.

What a prescriber weighs when considering a switch:

• Why you want to change, and whether the reason is side effects, convenience or something else
• How you responded to the current treatment and over what period
• What side effects you experienced, and at what point
• Your current weight and where it sits relative to where you started
• Whether the goal is continued loss or holding your current weight
• Any changes in your health or other medicines since you began
• Whether a gap in treatment is likely, and what that would mean

Bring those to the conversation. A switch driven by side effects leads somewhere different from one driven by preferring a weight loss tablet, and both are legitimate reasons to raise it.

Dose in the maintenance phase

There is no single maintenance dose that applies to everyone. The appropriate dose is determined by the prescriber according to treatment response and tolerability.

The current UK product information starts orforglipron at 0.8 mg once daily. After at least 30 days, the dose can be increased stepwise, with further increases made after at least 30 days at the current dose when appropriate. The maximum daily dose is 17.2 mg. More than one tablet should not be taken in a day to achieve a higher dose.

That does not mean everyone should work towards the maximum dose. Dose decisions should be based on the individual response and tolerability rather than on a schedule taken from an article.

Long term use and review

Ongoing treatment is reviewed rather than assumed, and that review is the mechanism through which long term use stays appropriate. It is also where the maintenance question is answered for you specifically rather than in general.

Foundayo was approved in 2026, so long term real world data is still building. The MHRA has said it will keep the safety and effectiveness of orforglipron under close review, which is standard for a newly approved medicine. Reporting suspected side effects through the Yellow Card scheme contributes directly to that picture, which matters more than usual with a recent approval.

Side effects in longer term use

Digestive effects lead the side effect picture across this family of medicines, including nausea, headaches, vomiting, diarrhoea or constipation, reduced appetite and indigestion. These generally show up strongly in the early stages, and some people notice them more after a dose increase, though individual experience varies considerably.

Less common but potentially serious problems, including acute pancreatitis and gallbladder disease, are described in the product information. The current UK SmPC also contains warnings relating to other potential adverse effects and advises appropriate clinical monitoring. Read the patient information leaflet supplied with your medicine rather than relying on a general summary, and speak to your prescriber if you have a relevant medical history or develop concerning symptoms.

What supports maintenance alongside medicine

Medicine is one part of maintenance, and national quality standards are explicit that support continues beyond it. The elements below are what that support looks like in practice.

• Regular weight monitoring, so a trend is spotted early rather than after months
• An action plan agreed in advance for what to do if weight starts to return
• Established routines around eating rather than a temporary regime
• Physical activity maintained, which contributes more to keeping weight off than to losing it
• Adequate protein intake and attention to nutrition, particularly where appetite is reduced
• Realistic expectations, including that small fluctuations are normal

That action plan point is the one people skip. Agreeing what you will do if weight begins to return, while things are going well, is considerably easier than deciding in the middle of it.

Medical Disclaimer

This article is for general information only and does not replace personal medical advice. It should not be used to decide on a treatment, to start, stop or change any medicine, or to delay seeking help. Foundayo is a prescription only medicine and eligibility is determined by an individual clinical assessment.

Always read the patient information leaflet supplied with your treatment, and speak to a pharmacist, GP or prescriber about your own circumstances and every medicine you take. If you use diabetes treatment, ask specifically about low blood sugar risk when medicines are combined or changed. Regulatory status and availability change, so confirm the current position before acting on anything here. Report suspected side effects through the Yellow Card scheme.