Foundayo vs Wegovy pill vs retatrutide (Reta)
Two pills reached the market in 2025–2026. A third compound, retatrutide, is still in trials. Below, their published results sit side by side: what each one is, how it is taken, what the trials showed and where each stands with regulators in Europe and the US. This is educational information. RetaNord supplies retatrutide for laboratory research use only.
| Foundayo | Wegovy pill | Retatrutide | |
|---|---|---|---|
| Maker | Eli Lilly | Novo Nordisk | Eli Lilly |
| Active substance | Orforglipron (small molecule) | Semaglutide 25 mg (peptide) | Retatrutide (peptide) |
| Receptors | GLP-1 | GLP-1 | GLP-1 + GIP + glucagon |
| Form | Daily tablet, no food or water rules | Daily tablet, empty stomach | Weekly injection (in trials) |
| Main obesity trial | ATTAIN-1: −12.4% at 72 weeks (placebo −0.9%) | OASIS 4: −16.6% at 64 weeks (placebo −2.7%) | TRIUMPH-1: −28.3% at 80 weeks (placebo −2.2%) |
| Stopped because of side effects | 10.3% vs 2.7% placebo | 6.9% vs 5.9% placebo | 11.3% vs 4.9% placebo |
| US status | Approved, 1 April 2026 | Approved, 22 December 2025 | Investigational |
| EU status | Recommended by the CHMP in October 2026; EU decision pending | Approved, 15 July 2026 | Investigational |
On this page
Two pills, one injection
Foundayo and the Wegovy pill both act only on the GLP-1 receptor, like Ozempic. The difference is the molecule. The Wegovy pill contains semaglutide, a peptide that needs special handling to survive the stomach. Foundayo contains orforglipron, a small molecule rather than a peptide, so the body absorbs it more easily.
Retatrutide is a peptide too, but it acts on three receptors (GLP-1, GIP and glucagon) and was given as a once-weekly injection in its trials. It is not available as a pill.
How the two pills are taken
Lilly states that Foundayo can be taken at any time of day, with no food or water restrictions. The Wegovy pill is taken in the morning on an empty stomach, with no more than half a glass (about 120 ml) of plain water. You then wait at least 30 minutes before eating, drinking or taking other medicines. For many people, this day-to-day difference matters as much as the trial numbers.
What the trials showed
Foundayo, ATTAIN-1: adults with obesity without diabetes lost on average 12.4% of their body weight after 72 weeks at the top dose, versus 0.9% on placebo.
Wegovy pill, OASIS 4: adults with obesity or overweight lost on average 16.6% after 64 weeks when they took it as intended, versus 2.7% on placebo (13.6% versus 2.2% counting everyone, whether they kept taking it or not).
Retatrutide, TRIUMPH-1: adults with obesity or overweight without diabetes lost on average 28.3% after 80 weeks on 12 mg, versus 2.2% on placebo.
All three headline figures describe the effect when the treatment is taken as intended. The trials differ in length, participants and design, so the numbers show a direction rather than a ranking. No trial has compared these three directly.
Wegovy injection vs retatrutide
Wegovy also comes as a weekly injection of semaglutide 2.4 mg, the dose tested in STEP 1. In that trial it lowered body weight by 14.9% at 68 weeks. Retatrutide 12 mg reached 28.3% at 80 weeks in TRIUMPH-1. These are again separate trials, so treat the gap as a direction rather than a ranking. The full comparison is in Ozempic vs retatrutide.
Side effects and stopping rates
All three cause the usual GLP-1 side effects in the stomach and gut: mostly nausea, diarrhoea, constipation and vomiting, usually while the dose is being increased. The share of people who stopped because of side effects was 10.3% with Foundayo (2.7% placebo), 6.9% with the Wegovy pill (5.9% placebo) and 11.3% with retatrutide 12 mg (4.9% placebo).
Approval status in Europe and the US (November 2026)
The Wegovy pill is approved in the US (22 December 2025) and in the EU (European Commission, 15 July 2026). Foundayo is approved in the US (1 April 2026) and the UK. In the EU, the CHMP recommended approval in October 2026, and the European Commission's decision is pending. Retatrutide is not approved anywhere; Lilly has reported Phase 3 results in 2026. See is retatrutide approved?
Where retatrutide fits
Retatrutide is the only one of the three that is not yet a medicine, and the only one that adds GIP and glucagon activity. That extra activity is the main reason its trial weight changes are larger. For more detail, see retatrutide vs orforglipron and Ozempic vs retatrutide.
Retatrutide vs Orforglipron: Triple-Agonist Injection vs GLP-1 Pill
Retatrutide and orforglipron are two of the most talked-about newer compounds in weight and metabolic research, and both come from Eli Lilly. They sit at opposite ends of the field: retatrutide is a weekly injection that acts on three receptors, while orforglipron is a daily pill that acts on one.
No trial has compared them directly yet, so this page sets their own trials side by side and explains how they differ. Everything here is educational and refers to published research. RetaNord supplies research compounds for laboratory research use only.
At a glance
| Retatrutide | Orforglipron | |
|---|---|---|
| Brand name | None yet (investigational) | Foundayo |
| Type of molecule | Peptide | Small molecule (not a peptide) |
| Receptors | GLP-1 + GIP + glucagon (triple) | GLP-1 (single) |
| Form in trials | Weekly injection | Daily tablet, no food or water restrictions |
| Main obesity trial (top dose) | TRIUMPH-1: −28.3% at 80 weeks | ATTAIN-1: −12.4% at 72 weeks |
| Stopped because of side effects (top dose vs placebo) | 11.3% vs 4.9% | 10.3% vs 2.7% |
| Status (October 2026) | Investigational, not approved in the US or the EU | Approved in the US (April 2026) and the UK (August 2026); in the EU recommended by the CHMP (October 2026), EU decision pending |
Three receptors versus one
Orforglipron is a single agonist: it activates only the GLP-1 receptor, the same target as semaglutide.
Retatrutide is a triple agonist: it activates the GLP-1, GIP and glucagon receptors. Glucagon is the extra piece; it is linked to energy use and fat metabolism in the liver, and it is the main reason retatrutide is described as a step beyond dual agonists such as tirzepatide.
A pill versus an injection
Most GLP-1 compounds are peptides: chains of amino acids that the gut would digest, so they are given by injection. Retatrutide is one of them and was given once a week in its trials.
Orforglipron is different. It is a small molecule, not a peptide, so it survives digestion and works as a once-daily tablet. Lilly states it can be taken at any time of day, with no food or water restrictions. Oral semaglutide (Rybelsus), by contrast, is a peptide tablet that has to be taken on an empty stomach.
What their trials show
- Retatrutide, TRIUMPH-1 (2026): 2,339 adults with obesity or overweight plus a weight-related condition, without diabetes. At the top dose, average body weight fell 28.3% after 80 weeks, versus 2.2% on placebo.
- Orforglipron, ATTAIN-1 (2025): 3,127 adults with obesity, without diabetes. At the top dose, average body weight fell 12.4% after 72 weeks, versus 0.9% on placebo. The results were published in the New England Journal of Medicine.
Both figures use the same type of analysis (the efficacy estimand). They come from separate trials with different people and lengths, so they are not a head-to-head comparison.
Side effects and dropouts
Both compounds share the typical GLP-1 pattern of stomach and gut side effects, mostly nausea, diarrhoea, constipation and vomiting. In the trials, the share of people who stopped treatment because of side effects at the top dose was:
- Retatrutide (12 mg): 11.3%, versus 4.9% on placebo.
- Orforglipron (36 mg): 10.3%, versus 2.7% on placebo.
Approval status in 2026
Orforglipron was approved by the US FDA on 1 April 2026 under the brand name Foundayo, for adults with obesity or overweight with weight-related conditions. The UK's MHRA authorised it on 10 August 2026, for weight management and type 2 diabetes. In the EU, the CHMP of the European Medicines Agency recommended approval in October 2026; the decision of the European Commission is pending.
Retatrutide is still investigational and is not approved in the US or the EU. Lilly has reported several Phase 3 TRIUMPH results in 2026.
Foundayo is a trademark of Eli Lilly. RetaNord is not a pharmacy and is not affiliated with Eli Lilly. It supplies research-grade compounds for laboratory and in-vitro research use only, not for human or veterinary use.
At RetaNord
RetaNord supplies retatrutide as 10 mg research vials at €89.95, each batch with a Certificate of Analysis. Orforglipron is not part of the RetaNord range. Supplied for laboratory research use only.
Sources
- Eli Lilly – FDA approves Foundayo (orforglipron), 1 April 2026
- Wharton et al. Orforglipron for obesity (ATTAIN-1). N Engl J Med 2025
- EMA – CHMP meeting highlights, 12–15 October 2026 (Foundayo recommended)
- Novo Nordisk – FDA approves Wegovy pill, 22 December 2025
- Novo Nordisk – European Commission approves Wegovy pill, 15 July 2026
- Eli Lilly – Retatrutide TRIUMPH-1 topline results, 21 May 2026
- Eli Lilly – Orforglipron ATTAIN-1 topline results, 16 September 2025
- UK MHRA – UK first in Europe to authorise orforglipron, 10 August 2026
- European Medicines Agency – CHMP agenda, 14–17 September 2026 (orforglipron, EMEA/H/C/006632)
Frequently asked questions
Is Foundayo the same as the Wegovy pill?
No. Foundayo contains orforglipron (Eli Lilly), a small molecule. The Wegovy pill contains semaglutide (Novo Nordisk), a peptide. Both act on the GLP-1 receptor and are taken once a day.
Which pill led to more weight loss in trials, Foundayo or Wegovy?
In their own trials, weight loss was about 16.6% at 64 weeks with the Wegovy pill and about 12.4% at 72 weeks with Foundayo. The trials were separate, so this is not a direct comparison.
Is retatrutide stronger than Wegovy?
In separate trials, yes, by a wide margin. Wegovy's semaglutide 2.4 mg injection gave 14.9% weight loss at 68 weeks (STEP 1), and retatrutide 12 mg gave 28.3% at 80 weeks (TRIUMPH-1). No trial has compared them directly, and retatrutide is not an approved medicine.
Is Foundayo approved in the EU?
Not yet. The EMA's CHMP recommended approval in October 2026, and the European Commission's decision is pending. The Wegovy pill was approved in the EU on 15 July 2026.
Is Foundayo the same as retatrutide?
No. Both come from Eli Lilly, but Foundayo (orforglipron) is a daily pill that acts on one receptor. Retatrutide is a weekly injection that acts on three receptors and is still investigational.
Is retatrutide available as a pill?
No. Retatrutide was given as a once-weekly injection in its trials, and it is not an approved medicine.
Is retatrutide stronger than orforglipron?
No trial has compared them directly. In their own main trials, retatrutide reached about 28% average weight loss at 80 weeks and orforglipron about 12% at 72 weeks, at their top doses.
What is Foundayo?
Foundayo is the brand name of orforglipron, a once-daily GLP-1 pill from Eli Lilly. The US FDA approved it on 1 April 2026.
Is orforglipron approved in Europe?
The UK authorised it in August 2026. In the EU, the CHMP of the European Medicines Agency recommended approval in October 2026; the decision of the European Commission is pending.
Is retatrutide approved?
No. Retatrutide is still investigational and is not approved in the US or the EU.