New daily weight-loss pill Foundayo approved in the UK: how does it work?
A new daily weight-loss tablet is set to give people in the UK another option for managing obesity without having to use an injection.
The medicine, called Foundayo, contains the active ingredient orforglipron and has been approved by the UK Medicines and Healthcare products Regulatory Agency, or MHRA. It is made by Eli Lilly, the pharmaceutical company behind Mounjaro.
Unlike Mounjaro, which is given as an injection, Foundayo is taken once a day as a tablet. The drug belongs to a group of medicines known as GLP-1 receptor agonists, which work by influencing the body's natural appetite and blood sugar control systems.
The UK approval means the medicine could become available through prescription in the coming weeks, although NHS availability is a separate question and depends on decisions around cost effectiveness and prescribing criteria.
What is Foundayo?
Foundayo is the brand name for orforglipron, a once-daily oral GLP-1 medicine.
GLP-1 stands for glucagon-like peptide-1, a hormone naturally produced in the body. After eating, GLP-1 helps send signals involved in appetite, digestion and blood sugar regulation.
Some modern weight-loss medicines work by copying or enhancing these signals. The result can be a reduction in hunger and an increased feeling of fullness, which can make it easier for someone to eat less.
Orforglipron is particularly notable because it is a small-molecule, non-peptide GLP-1 receptor agonist. This helps explain why it can be developed as a conventional tablet rather than requiring injection.
How does the new pill work?
The simplest way to understand Foundayo is to think of it as helping the body strengthen some of the signals that naturally tell you that you have eaten enough.
After food enters the digestive system, GLP-1 is one of the hormones involved in communicating with the brain and other organs. GLP-1 receptor agonists activate the same receptor pathways.
Orforglipron binds to GLP-1 receptors, helping produce effects associated with natural GLP-1 activity.
One important effect is appetite reduction.
When appetite is reduced and feelings of fullness last longer, people may find they naturally eat fewer calories. Over time, this can contribute to weight loss when the medicine is combined with a reduced-calorie diet and increased physical activity.
The drug also affects blood glucose regulation. GLP-1 receptor agonists can increase insulin secretion when blood glucose is elevated and reduce glucagon secretion, helping the body manage blood sugar more effectively.
This is one reason orforglipron is also being used as a treatment option for adults with type 2 diabetes.
Clinical trials have found improvements in blood sugar as well as reductions in body weight. In the Phase 3 ACHIEVE-1 trial involving people with type 2 diabetes, the highest studied dose reduced HbA1c by an average of 1.6 percentage points at 40 weeks and was associated with average weight loss of 7.9 per cent.
Why is taking it as a pill significant?
Many people are already familiar with GLP-1 medicines such as Wegovy and Mounjaro.
The biggest practical difference with Foundayo is the way it is taken.
Orforglipron is designed to be taken once daily without the food and water restrictions associated with some other oral GLP-1 medicines. Lilly's clinical development programme has described it as a tablet that can be taken without regard to meals.
For people who dislike needles, a tablet could make treatment more convenient.
That does not mean the pill is automatically better than an injection. Different medicines work differently, and the most suitable treatment depends on a person's health, medical history, other medicines and treatment goals.
How much weight can people lose?
The amount of weight lost varies considerably between individuals.
In the Phase 3 ATTAIN-1 trial, participants taking the highest dose of orforglipron lost an average of 12.4 per cent of their body weight after 72 weeks, compared with 0.9 per cent among people taking placebo, using the study's efficacy analysis.
That does not mean everyone taking Foundayo will lose 12.4 per cent.
Clinical trial averages describe what happened across a large group of participants. Individual results can be higher or lower, and some people may stop treatment because of side effects or other reasons.
The trials also found improvements in several factors associated with cardiometabolic health, including waist circumference, blood pressure, triglycerides and non-HDL cholesterol.
Is Foundayo the same as Mounjaro?
No.
Although both medicines are made by Eli Lilly and can help with weight management, they are not the same drug.
Mounjaro contains tirzepatide, which acts on both GLP-1 and GIP receptors. Foundayo contains orforglipron, which is a GLP-1 receptor agonist.
This distinction matters because the medicines have different mechanisms, dosing schedules and clinical evidence.
Foundayo should therefore be viewed as another treatment within the wider GLP-1 medicine category rather than simply a "pill version" of Mounjaro.
What about side effects?
Like other medicines in the GLP-1 family, orforglipron can cause gastrointestinal side effects.
Clinical trials reported problems including nausea, diarrhoea, vomiting, constipation and indigestion. These effects were generally mild to moderate in the studies, although some participants discontinued treatment because of adverse events.
Anyone considering the medication should discuss potential risks and benefits with a qualified healthcare professional.
A prescription weight-loss medicine is not a substitute for medical assessment, and people should not buy GLP-1 medicines from unverified websites or use someone else's prescription.
Who could be eligible in the UK?
The reported UK approval covers adults who meet medical criteria for weight management, including people living with obesity and some people who are overweight and have an associated health condition.
Treatment is intended to be used alongside lifestyle measures such as a healthy diet and physical activity.
However, regulatory approval does not automatically mean everyone who meets the criteria will receive the medicine through the NHS.
NHS access can involve additional decisions about cost effectiveness, local prescribing arrangements and which patient groups should be prioritised.
A new chapter for weight-loss treatment
The arrival of an oral GLP-1 medicine could make weight-management treatment more accessible and convenient for some people.
The science behind Foundayo is based on a relatively simple principle: activate GLP-1 receptors, influence appetite and fullness, improve aspects of blood sugar regulation and, when combined with lifestyle changes, support meaningful weight loss.
Its results are promising, but it is not a miracle solution. Obesity is a complex, long-term health condition, and medication is only one part of treatment.
For people who are medically eligible, however, a once-daily tablet could offer an alternative to injections and expand the range of treatments available.
As Foundayo enters the UK market, the key question will no longer simply be whether an effective GLP-1 treatment can come in tablet form. It will be how patients, doctors and health services use this new option safely and appropriately.
Sources: MHRA and UK regulatory reporting; Eli Lilly clinical trial data; The New England Journal of Medicine reports on the ATTAIN programme; Reuters and Guardian reporting on the UK weight-loss medicine market.