Skip to content

GLP-1 research overview: the main trial behind each approved use

Updated Sep 30, 2026. Numbers in brackets link to the source each fact comes from.

This page lists, for each use on the current FDA labels of Wegovy, Zepbound, Foundayo, Ozempic and Mounjaro, the main trial the label describes and its headline result from the published abstract. We matched each trial to its label by the ClinicalTrials.gov number printed in the label’s clinical studies section.

The approved uses themselves, in each label’s words, are on what each GLP-1 is approved for. The weight-loss numbers as the labels print them are on weight loss results.

Wegovy (semaglutide)

Approved use Main trial Headline result
Weight reduction, adults [1] STEP 1, 68 weeks -14.9% body weight vs -2.4% on placebo [2]
Weight reduction, ages 12 and older with obesity [1] STEP TEENS, 68 weeks BMI -16.1% vs +0.6% on placebo [30]
Optional 7.2 mg dose after 2.4 mg [3] STEP UP, 72 weeks -18.7% on 7.2 mg vs -15.6% on 2.4 mg and -3.9% on placebo [4]
Lower risk of heart attack, stroke or cardiovascular death in people with heart disease and obesity or overweight [5] SELECT Events in 6.5% vs 8.0% on placebo, hazard ratio 0.80 [6]
MASH with moderate to advanced liver scarring, accelerated approval [7] ESSENCE, week 72 interim Steatohepatitis resolved in 62.9% vs 34.3% on placebo [8]

Wegovy tablets (oral semaglutide)

Approved use Main trial Headline result
Weight reduction, adults [9] OASIS 4, 64 weeks -13.6% body weight vs -2.2% on placebo [10]
Lower risk of major cardiovascular events [11] No separate tablet trial in the label The label’s only cardiovascular outcomes trial is SELECT, which tested the injection [31]

Novo Nordisk says the tablet approval rests on its OASIS trials together with the SELECT trial [32]. The label adds a link between the two forms: in people with overweight or obesity who do not have type 2 diabetes, blood levels of semaglutide from the 25 mg tablet are predicted to be comparable to those from the 2.4 mg weekly injection [33].

Zepbound (tirzepatide)

Approved use Main trial Headline result
Weight reduction, adults [12] SURMOUNT-1, 72 weeks -15.0%, -19.5% and -20.9% on 5, 10 and 15 mg vs -3.1% on placebo [13]
Moderate to severe obstructive sleep apnea with obesity [14] SURMOUNT-OSA, 52 weeks Breathing interruptions fell by 25.3 per hour vs 5.3 on placebo, in the trial of people not using positive airway pressure (PAP) [15]

Foundayo (orforglipron)

Approved use Main trial Headline result
Weight reduction, adults [16] ATTAIN-1, 72 weeks -7.5%, -8.4% and -11.2% on the three doses vs -2.1% on placebo [17]

The trial used an investigational formulation of orforglipron, and the label presents its results under Foundayo dose names [18]. The published trial reports doses of 6, 12 and 36 mg [17], while the label reports the same trial under Foundayo doses of 5.5, 9 and 17.2 mg [29].

Ozempic (semaglutide, type 2 diabetes)

Approved use Main trial Headline result
Blood sugar control in adults with type 2 diabetes [19] SUSTAIN 1, 30 weeks HbA1c fell 1.45 and 1.55 percentage points on 0.5 and 1 mg vs 0.02 on placebo [20]
Lower risk of heart attack, stroke or cardiovascular death with type 2 diabetes and heart disease [21] SUSTAIN 6 Events in 6.6% vs 8.9% on placebo, hazard ratio 0.74 [22]
Lower risk of kidney decline, kidney failure and cardiovascular death with type 2 diabetes and chronic kidney disease [23] FLOW 24% lower risk of the main kidney outcome, hazard ratio 0.76 [24]

Mounjaro (tirzepatide, type 2 diabetes)

Approved use Main trial Headline result
Blood sugar control in adults and children 10 and older with type 2 diabetes [25] SURPASS-1, 40 weeks HbA1c fell 1.87 to 2.07 percentage points vs a 0.04 rise on placebo [26]
Lower risk of major cardiovascular events with type 2 diabetes at high risk [27] SURPASS-CVOT, compared with dulaglutide Events in 12.2% vs 13.1% on dulaglutide; shown not worse, not shown better [28]

How to read these results

  • One line is not the whole trial. Each row gives the main measure only. Side effects, dropouts and other results are in the abstracts linked in the sources below and in each label.
  • Do not compare across rows. Trials enrolled different people, ran for different lengths and measured results in different ways. A bigger number in one row does not prove one medicine beats another.
  • SURPASS-CVOT had no placebo group. It compared tirzepatide with another GLP-1 medicine, dulaglutide, so its result says tirzepatide was no worse, not how it compares with no treatment [28].
  • Heart failure and fatty liver on Zepbound are not approved uses. Trials exist, but they are not on the label. See Zepbound for heart failure and Zepbound for fatty liver.

This page summarizes published research and is not medical advice. Which medicine and dose fit you is a decision for your prescriber.

Sources

  1. adults and pediatric patients aged 12 years and older with obesity. dailymed.nlm.nih.gov, read Sep 27, 2026.
  2. The mean change in body weight from baseline to week 68 was -14.9% in the semaglutide group as compared with -2.4% with placebo pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  3. For patients who tolerate the 2.4 mg dosage for at least 4 weeks and additional weight reduction is clinically indicated, the dosage may be increased to a maximum dosage of 7.2 mg subcutaneously once weekly. dailymed.nlm.nih.gov, read Sep 27, 2026.
  4. The mean change in bodyweight was greater with semaglutide 7·2 mg versus 2·4 mg (-18·7% [SE 0·4] vs -15·6% [0·7]; estimated treatment difference [ETD] -3·1% [95% CI -4·7 to -1·6]; p<0·0001) and with semaglutide 7·2 mg versus placebo (-18·7% [0·4] vs -3·9% [0·6]; -14·8% [-16·2 to -13·4]; p<0·0001). pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  5. to reduce the risk of major adverse cardiovascular (CV) events (CV death, non-fatal myocardial infarction, or non-fatal stroke) in adults with established CV disease and either obesity or overweight. dailymed.nlm.nih.gov, read Sep 27, 2026.
  6. A primary cardiovascular end-point event occurred in 569 of the 8803 patients (6.5%) in the semaglutide group and in 701 of the 8801 patients (8.0%) in the placebo group (hazard ratio, 0.80; 95% confidence interval, 0.72 to 0.90; P<0.001). pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  7. for the treatment of noncirrhotic metabolic dysfunction-associated steatohepatitis (MASH), formerly known as nonalcoholic steatohepatitis (NASH), with moderate to advanced liver fibrosis (consistent with stages F2 to F3 fibrosis) in adults. This indication is approved under accelerated approval based on improvement of MASH and fibrosis. dailymed.nlm.nih.gov, read Sep 27, 2026.
  8. Resolution of steatohepatitis without worsening of fibrosis occurred in 62.9% of the 534 patients in the semaglutide group and in 34.3% of the 266 patients in the placebo group pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  9. to reduce excess body weight and maintain weight reduction long term in adults with obesity, or in adults with overweight in the presence of at least one weight-related comorbid condition. dailymed.nlm.nih.gov, read Sep 27, 2026.
  10. The estimated mean change in body weight from baseline to week 64 was -13.6% in the oral semaglutide group and -2.2% in the placebo group pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  11. to reduce the risk of major adverse CV events (CV death, non-fatal myocardial infarction, or non-fatal stroke) in adults with established CV disease and either obesity or overweight. dailymed.nlm.nih.gov, read Sep 27, 2026.
  12. to reduce excess body weight and maintain weight reduction long term in adults with obesity or adults with overweight in the presence of at least one weight-related comorbid condition. dailymed.nlm.nih.gov, read Sep 27, 2026.
  13. The mean percentage change in weight at week 72 was -15.0% (95% confidence interval [CI], -15.9 to -14.2) with 5-mg weekly doses of tirzepatide, -19.5% (95% CI, -20.4 to -18.5) with 10-mg doses, and -20.9% (95% CI, -21.8 to -19.9) with 15-mg doses and -3.1% (95% CI, -4.3 to -1.9) with placebo pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  14. to treat moderate to severe obstructive sleep apnea (OSA) in adults with obesity. dailymed.nlm.nih.gov, read Sep 27, 2026.
  15. In trial 1, the mean change in AHI at week 52 was -25.3 events per hour (95% confidence interval [CI], -29.3 to -21.2) with tirzepatide and -5.3 events per hour (95% CI, -9.4 to -1.1) with placebo pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  16. is a GLP-1 receptor agonist indicated in combination with a reduced-calorie diet and increased physical activity to reduce excess body weight and maintain weight reduction long term in adults with obesity or adults with overweight in the presence of at least one weight-related comorbid condition. dailymed.nlm.nih.gov, read Sep 27, 2026.
  17. The mean change in body weight from baseline to week 72 was -7.5% (95% confidence interval [CI], -8.2 to -6.8) with 6 mg of orforglipron, -8.4% (95% CI, -9.1 to -7.7) with 12 mg of orforglipron, and -11.2% (95% CI, -12.0 to -10.4) with 36 mg of orforglipron, as compared with -2.1% (95% CI, -2.8 to -1.4) with placebo pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  18. based on adequate and well-controlled trials of an investigational orforglipron formulation (Trials 1 and 2), referred to in this section as FOUNDAYO. dailymed.nlm.nih.gov, read Sep 27, 2026.
  19. as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. dailymed.nlm.nih.gov, read Sep 27, 2026.
  20. at week 30, HbA1c significantly decreased by 1·45% (95% CI -1·65 to -1·26) with 0·5 mg semaglutide (estimated treatment difference vs placebo -1·43%, 95% CI -1·71 to -1·15; p<0·0001), significantly decreased by 1·55% (-1·74 to -1·36) with 1·0 mg semaglutide (estimated treatment difference vs placebo -1·53%, -1·81 to -1·25; p<0·0001), and non-significantly decreased by 0·02% (-0·23 to 0·18) with placebo. pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  21. to reduce the risk of major adverse cardiovascular events (cardiovascular death, non-fatal myocardial infarction or non-fatal stroke) in adults with type 2 diabetes mellitus and established cardiovascular disease. dailymed.nlm.nih.gov, read Sep 27, 2026.
  22. The primary outcome occurred in 108 of 1648 patients (6.6%) in the semaglutide group and in 146 of 1649 patients (8.9%) in the placebo group (hazard ratio, 0.74; 95% confidence interval [CI], 0.58 to 0.95; P<0.001 for noninferiority). pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  23. to reduce the risk of sustained eGFR decline, end-stage kidney disease, and cardiovascular death in adults with type 2 diabetes mellitus and chronic kidney disease. dailymed.nlm.nih.gov, read Sep 27, 2026.
  24. The risk of a primary-outcome event was 24% lower in the semaglutide group than in the placebo group (331 vs. 410 first events; hazard ratio, 0.76; 95% confidence interval [CI], 0.66 to 0.88; P = 0.0003). pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  25. as an adjunct to diet and exercise to improve glycemic control in adults and pediatric patients 10 years of age and older with type 2 diabetes mellitus. dailymed.nlm.nih.gov, read Sep 27, 2026.
  26. Mean HbA1c decreased from baseline by 1·87% (20 mmol/mol) with tirzepatide 5 mg, 1·89% (21 mmol/mol) with tirzepatide 10 mg, and 2·07% (23 mmol/mol) with tirzepatide 15 mg versus +0·04% with placebo (+0·4 mmol/mol) pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  27. to reduce the risk of major adverse cardiovascular (CV) events (CV death, non-fatal myocardial infarction (MI), or non-fatal stroke) in adults with type 2 diabetes mellitus who are at high risk for these events. dailymed.nlm.nih.gov, read Sep 27, 2026.
  28. A primary end-point event occurred in 801 patients (12.2%) in the tirzepatide group and 862 (13.1%) in the dulaglutide group (hazard ratio, 0.92; 95.3% confidence interval, 0.83 to 1.01; P = 0.003 for noninferiority; P = 0.09 for superiority). pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  29. Intent-to-Treat (ITT) Populationa Placebo once daily N = 949 FOUNDAYO 5.5 mg once daily N = 723 FOUNDAYO 9 mg once daily N = 725 FOUNDAYO 17.2 mg once daily N = 730 dailymed.nlm.nih.gov, read Sep 27, 2026.
  30. The mean change in BMI from baseline to week 68 was -16.1% with semaglutide and 0.6% with placebo (estimated difference, -16.7 percentage points; 95% confidence interval [CI], -20.3 to -13.2; P<0.001). pubmed.ncbi.nlm.nih.gov, read Sep 27, 2026.
  31. Study 1 (NCT03574597) was a multi-national, multi-center, placebo-controlled, double-blind trial to determine the effect of WEGOVY injection relative to placebo on major adverse CV events (MACE) dailymed.nlm.nih.gov, read Sep 27, 2026.
  32. The approval is based on the OASIS trial programme and the SELECT trial novonordisk.com, read Sep 28, 2026.
  33. In patients with overweight or obesity without type 2 diabetes, semaglutide concentrations following once-daily administration of oral WEGOVY 25 mg tablet are predicted to be comparable to WEGOVY 2.4 mg once-weekly injection dailymed.nlm.nih.gov, read Sep 28, 2026.

This page reports what official sources say; it is not medical advice. Medical disclaimer.