Mounjaro®
Starting from £179.99/mo
Start journey Learn moreThe practical factors that should shape your thinking on this comparison
The decision you're actually facing here
Most people searching this comparison are trying to work out whether to start semaglutide now or wait for orforglipron. That is a reasonable question. It is also worth addressing the misconception that orforglipron is essentially "the next Wegovy", it is a structurally different molecule, not a reformulation, and phase 3 trials are still running.
Semaglutide (Wegovy injection) is GLP-1 receptor agonist therapy that has been through the full UK regulatory process. The MHRA licensed it for weight management, NICE appraised it under TA875, and NHS England has defined when it can be prescribed on the health service. That regulatory scaffolding took years to build. Orforglipron, developed by Eli Lilly, does not yet have a UK marketing authorisation for weight management, it is in phase 3 trials, and no approval timeline for the UK has been confirmed publicly.
For anyone who wants to start treatment now, semaglutide is the licensed option. If you are curious about how GLP-1 medicines work as a class, that background helps contextualise both molecules. The rest of this page lays out what the evidence actually shows, side by side, so you can have a more informed conversation with a prescriber.
What the trial data shows so far
Semaglutide 2.4 mg was tested in the STEP 1 trial over 68 weeks. Participants lost an average of around 15% of body weight, published in the New England Journal of Medicine. A higher 7.2 mg dose received MHRA approval in 2026, with trials reporting around 20.7% average loss at that level. This is a once-weekly subcutaneous injection.
Orforglipron's phase 2 data (published 2023) showed weight reductions of roughly 9–14.7% over 36 weeks across dose groups, in people without diabetes. Phase 3 results are not yet published. Critically, orforglipron is taken as a daily oral tablet and, unlike the Wegovy pill (oral semaglutide, approved by the MHRA on 11 June 2026), does not require the strict fasting protocol, it can be taken without regard to food or water timing. That is a genuine practical difference worth noting.
Oral semaglutide for weight loss is itself now licensed in the UK, the Wegovy tablet reached approval ahead of orforglipron. A comparison of semaglutide formulations may be helpful if the injection versus tablet question is what you are weighing.
| Factor | Semaglutide (Wegovy) | Orforglipron |
|---|---|---|
| UK marketing authorisation for weight loss | Yes (injection and tablet) | No (phase 3 trials ongoing as of mid-2026) |
| Mechanism | GLP-1 receptor agonist (peptide) | GLP-1 receptor agonist (non-peptide, small molecule) |
| Route | Once-weekly injection or once-daily tablet | Once-daily oral tablet |
| Food restrictions on oral form | Yes, 30-min fast required for tablet [Source: MHRA, Jun 2026] | None reported in phase 2 data |
| Average weight loss (headline figure) | ~15% at 2.4 mg / ~20.7% at 7.2 mg over 68–72 weeks [NEJM; MHRA] | ~9–14.7% over 36 weeks (phase 2; no phase 3 data yet) |
| Available to prescribe in the UK now | Yes, via private prescription or NHS criteria | No |
Side effects and tolerability: what the profiles look like
Both molecules act on the same receptor, so the side-effect terrain has similarities. Semaglutide's profile is well-characterised: nausea, vomiting, diarrhoea, constipation and fatigue are the most commonly reported effects, typically most noticeable after starting or a dose increase and often settling within a fortnight. The NHS semaglutide page covers these in plain language.
Orforglipron's phase 2 data showed a broadly similar GI-led profile. Tolerability rates in the phase 3 programme will be the more informative measure, but those results are not public yet. Because orforglipron is a small molecule rather than a peptide, it does not require an absorption enhancer, which is part of why the fasting restriction is absent, that manufacturing difference may have tolerability implications that longer trials will clarify.
For semaglutide, pancreatitis is listed as an infrequent but potentially serious risk; anyone experiencing severe, persistent stomach pain should get medical help promptly. The MHRA published a Drug Safety Update on this in January 2026. Reporting any unexpected effects from licensed medicines is straightforward via the Yellow Card scheme.
On contraception: women taking oral contraceptives alongside the Wegovy tablet should discuss timing and additional contraceptive methods with their prescriber. There is no equivalent data for orforglipron yet, another reason a prescriber-led discussion matters here.
What this means for anyone deciding now
The honest answer is that orforglipron could become a meaningful option once phase 3 data are published and a regulatory submission follows. That process typically takes years. If you want to understand how semaglutide is used across different licensed products, that context is useful before speaking to a prescriber.
If you are in two minds about which GLP-1 medicine is right for you, the comparison between dulaglutide and semaglutide or between liraglutide and semaglutide might also be worth reading, depending on what your GP has mentioned. But for weight management treatment starting in 2025 or 2026, the practical field is Wegovy (injection or tablet), Mounjaro (tirzepatide), and orlistat. Orforglipron is not yet in that field.
Which of the licensed options suits you is a clinical decision, not a search-results one. Our prescribers at nume review every consultation the same day, a named clinician reads your answers and makes that call with you. If you are ready to explore your options, start your free consultation and we will take it from there.
Looking to start your weight loss journey?
Take a quick eligibility quiz to explore your options and see how we can support you.