Orforglipron vs oral semaglutide: two oral GLP-1 pills compared

Key points

• Two oral GLP-1 products are FDA-approved for chronic weight management in the US: Lilly’s Foundayo (orforglipron, a small molecule, 1 April 2026) and Novo Nordisk’s Wegovy pill (oral semaglutide, a peptide, 22 December 2025) [1][2].
• In placebo-controlled trials in adults without diabetes, orforglipron reached -11.2 percent at 72 weeks (top trial arm) and oral semaglutide 25 mg reached -13.6 percent at 64 weeks (both treatment-regimen analyses). The trials differ in design, so the numbers are not a direct comparison [3][4].
• No head-to-head trial in obesity exists that we could find. One in type 2 diabetes (ACHIEVE-3, 1,698 adults, Lilly-sponsored) compared orforglipron with oral semaglutide [5].
• The labels differ on administration: the Wegovy pill label sets food, water and waiting-time conditions; the Foundayo label text we read lists none [6][7].

What each product is

Orforglipron is an oral, non-peptide small-molecule GLP-1 receptor agonist. Lilly’s brand name is Foundayo; Lilly’s 10-Q states the two are the same drug [8]. The FDA approved it on 1 April 2026 to reduce excess body weight and maintain the reduction in adults with obesity, or with overweight and at least one weight-related condition. The FDA said approval rested on two randomized, double-blind, placebo-controlled 72-week trials and called it the first new molecular entity approved under its Commissioner’s National Priority Voucher pilot [2]. For the company side, see Eli Lilly’s GLP-1 business.

Oral semaglutide is the peptide semaglutide formulated as a tablet. It is sold as Rybelsus and as Ozempic tablets for type 2 diabetes (one shared label), and as the Wegovy pill for weight management [6][9]. Novo announced FDA approval of the Wegovy pill on 22 December 2025, for weight reduction and maintenance and for reducing major cardiovascular events [1]. The current label lists the cardiovascular indication for adults with established cardiovascular disease and obesity or overweight [6]. See Novo Nordisk’s GLP-1 business.

Regulatory status

	Foundayo (orforglipron)	Wegovy pill	Rybelsus / Ozempic tablets
US FDA	Approved 1 April 2026: weight management [2]. Label revised July 2026 [7]	Approved 22 December 2025: weight management and cardiovascular risk reduction [1]. Label revised June 2026 [6]	Type 2 diabetes; cardiovascular risk reduction in type 2 diabetes. Label revised January 2026 [9]
Boxed warning	Thyroid C-cell tumors (rodents) [7]	Same [6]	Same [9]
Prescription status	Prescription medicine [7]	Prescription medicine [6]	Prescription medicine [9]

Lilly’s 10-Q says a type 2 diabetes submission is pending in the US [8]. We checked only US sources. The EU, UK and Germany registers were not checked for this article; the company overviews report some European decisions with their own caveats.

The pivotal trials

All figures are from the papers or labels named. Weight-loss figures are mean percentage change from baseline, and the estimand (the analysis rule) is given because it moves the numbers. Every trial listed was funded by the product’s manufacturer.

Trial	Product	Population	Size and length	Weight result	Discontinued for adverse events	GI events	Funder
ATTAIN-1 [3]	Orforglipron (arms 6, 12, 36 mg) vs placebo	Obesity, no diabetes	3,127; 72 weeks	-7.5%, -8.4%, -11.2% vs -2.1% (treatment regimen)	5.3 to 10.3% vs 2.7%	“mostly mild to moderate” GI events (see label rates below)	Eli Lilly
ATTAIN-2 [10]	Orforglipron (6, 12, 36 mg) vs placebo	Obesity or overweight with type 2 diabetes	1,613; 72 weeks	-5.1%, -7.0%, -9.6% vs -2.5%	6.1 to 9.9% vs 4.1%	mainly GI	Eli Lilly
OASIS 4 [4]	Oral semaglutide 25 mg vs placebo	Overweight or obesity, no diabetes	307 (205 vs 102); 64 weeks on treatment, 71 weeks in total	-13.6% vs -2.2% (company release: -16.6% if all adhered [1])	6.9% vs 5.9% (label) [6]	74.0% vs 42.2%	Novo Nordisk
OASIS 1 [11]	Oral semaglutide 50 mg vs placebo	Overweight or obesity, no diabetes	667; 68 weeks	-15.1% vs -2.4%	not retrieved	80% vs 46%	Novo Nordisk, Steno Diabetes Center Copenhagen
PIONEER program (label trials 1 to 5) [9]	Oral semaglutide 7 and 14 mg vs placebo or active comparators	Type 2 diabetes	324 to 1,864 per trial; 26 weeks	Trial 1: -3.7 kg (14 mg) vs -1.4 kg placebo	GI reasons: 8% (14 mg), 4% (7 mg), 1% (placebo)	nausea 20% (14 mg) vs 6%	Not stated in the label; papers not opened

Further detail follows.

ATTAIN-1 (NCT05869903, published in the New England Journal of Medicine in 2025) randomized adults with obesity but no diabetes. In the top arm 54.6 percent lost at least 10 percent of body weight, against 12.9 percent on placebo [3]. The FDA label, which names arms as 5.5, 9 and 17.2 mg, reports pooled placebo-controlled data from 3,155 patients: 8 percent of orforglipron patients stopped permanently because of adverse reactions, against 3 percent on placebo. In the highest labelled strength, nausea was 35 percent (placebo 10), vomiting 24 percent (4), diarrhea 25 percent (11) and constipation 24 percent (9) [7]. We did not verify how the label’s strengths map to the trial’s arms.

ATTAIN-2 (NCT05872620, The Lancet, online 20 November 2025) enrolled adults with type 2 diabetes and HbA1c 7 to 10 percent at 136 sites in ten countries. Ten deaths occurred, six on orforglipron and four on placebo; the investigators judged nearly all unrelated to treatment [10].

OASIS 4 (NCT05564117, New England Journal of Medicine, September 2025) ran at 22 sites in four countries. The authors reported the 64-week change of -13.6 percent against -2.2 percent, an estimated difference of -11.4 percentage points [4]. The Wegovy label describes a tablet study of 204 adults over up to 64 weeks (it does not use the name OASIS 4), with 5 percent of tablet patients reporting dysesthesia against none on placebo [6].

OASIS 1 (NCT05035095, The Lancet, 2023) tested 50 mg, a higher strength than the 25 mg now approved for weight management [11][6]. It is therefore evidence about the drug class, not about the marketed tablet.

PIONEER is the type 2 diabetes program behind Rybelsus. The label (which numbers rather than names its trials) lists 703 to 1,864 patients per 26-week trial and a cardiovascular outcomes trial with 4,825 patients per arm and about 49.5 months of median follow-up. In that outcomes trial 15.5 percent on semaglutide stopped for an adverse event, against 11.6 percent on placebo [9]. These are diabetes results with diabetes-sized weight changes and should not be read as obesity efficacy.

Head-to-head data

In obesity there is no direct comparison that we found in ClinicalTrials.gov or Europe PMC. In type 2 diabetes there is ACHIEVE-3 (NCT06045221): 1,698 adults on metformin, 52 weeks, open label, non-inferiority, sponsored by Lilly. HbA1c fell by 1.71 percent (orforglipron 12 mg) and 1.91 percent (36 mg), against 1.23 percent (oral semaglutide 7 mg) and 1.47 percent (14 mg) [5]. GI adverse events were 58 to 59 percent with orforglipron and 37 to 45 percent with oral semaglutide. Discontinuation for adverse events was 9 and 10 percent against 4 and 5 percent. Mean pulse rose 3.7 and 4.7 beats a minute on orforglipron and 1.0 and 1.5 on semaglutide [5]. This is a company-run trial in a different population and compares HbA1c, not obesity outcomes.

Administration conditions as the labels state them

The Wegovy pill label says the tablet is taken on an empty stomach in the morning with up to 4 ounces of water only, swallowed whole, with at least 30 minutes before eating, drinking or taking other oral medicines [6]. The Rybelsus and Ozempic tablet label gives the same conditions and says the two tablets are not substitutable milligram for milligram [9]. The Foundayo label text we read says it is taken once daily with or without food, swallowed whole, and lists no water restriction [7]. We read the first 100,000 characters of the 136,652-character label page, so a condition elsewhere in the text is possible. Novo’s approval release gave no food or water details [1]. Doses are not discussed here.

The orforglipron label also says delayed gastric emptying may change absorption of other oral medicines, and for oral hormonal contraceptives it advises a non-oral or backup method for 30 days after starting and after each increase [7].

Risks and unknowns

Documented risks. All three labels carry a boxed warning for thyroid C-cell tumors seen in rodents, and the human relevance has not been determined; the products are contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2 [6][7][9]. Foundayo warnings include acute pancreatitis, severe gastrointestinal reactions (not recommended in severe gastroparesis), acute kidney injury from volume depletion, hypoglycemia with insulin or secretagogues, hypersensitivity, diabetic retinopathy complications, acute gallbladder disease and pulmonary aspiration during anesthesia or deep sedation [7]. The Wegovy tablet label lists a similar set plus heart-rate increase, and a drug interaction study found levothyroxine exposure rose 33 percent [6]. The Foundayo label says it may cause fetal harm and is not recommended during breastfeeding; the Wegovy pregnancy text was not retrieved [7].

Interactions specific to orforglipron. The label limits exposure with strong CYP3A4 inhibitors, advises avoiding strong inducers, and gives a limit with simvastatin [7].

Unknown.

• Head-to-head efficacy in obesity; cross-trial differences in populations, estimands and durations make the percentages non-comparable.
• Long-term safety and cardiovascular outcomes for orforglipron in obesity. We found no completed outcomes trial for it in obesity; the oral semaglutide outcomes data come from a diabetes trial [9].
• How weight is regained after stopping; we did not retrieve data for either product.
• Real-world GI tolerability outside trials, and what happens in people excluded from trials (the Wegovy tablet study excluded type 2 diabetes) [6].
• OASIS 1 discontinuation rates and the PIONEER funders were not retrieved. We did not open the trial papers for ATTAIN-1 beyond the abstract, so the full adverse event tables are untested here.

Frequently asked questions

Is orforglipron the same as Foundayo? Yes. Lilly’s 10-Q states orforglipron is branded as Foundayo, and the FDA approved it for chronic weight management on 1 April 2026 [2][8].

Is the Wegovy pill the same as Rybelsus? Both are oral semaglutide but they are separate products with separate indications. The Wegovy pill is approved for weight management and cardiovascular risk reduction; Rybelsus and Ozempic tablets are approved for type 2 diabetes [6][9].

Which pill leads to more weight loss? There is no head-to-head obesity trial. In separate placebo-controlled trials, orforglipron’s top arm gave -11.2 percent at 72 weeks and oral semaglutide 25 mg gave -13.6 percent at 64 weeks; different populations and designs mean these cannot be ranked [3][4].

Do the pills have the same side effects? The leading adverse events for both are gastrointestinal, and both carry the same boxed warning. In the one direct trial, in type 2 diabetes, GI events and discontinuations were higher on orforglipron than on oral semaglutide [5].

Sources

1. Novo Nordisk A/S, Form 6-K, announcement of FDA approval of the Wegovy pill (2025-12-22). https://www.sec.gov/Archives/edgar/data/353278/000117184325008080/f6k_122225.htm
2. U.S. Food and Drug Administration, “FDA Approves First New Molecular Entity Under National Priority Voucher Program” (2026-04-01). https://www.fda.gov/news-events/press-announcements/fda-approves-first-new-molecular-entity-under-national-priority-voucher-program
3. Wharton S et al., “Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment,” N Engl J Med 393(18):1796-1806 (2025), PMID 40960239, read via Europe PMC. https://pubmed.ncbi.nlm.nih.gov/40960239/
4. Wharton S et al., “Oral Semaglutide at a Dose of 25 mg in Adults with Overweight or Obesity,” N Engl J Med 393(11):1077-1087 (2025), PMID 40934115, read via Europe PMC. https://pubmed.ncbi.nlm.nih.gov/40934115/
5. “Efficacy and safety of once-daily oral orforglipron compared with oral semaglutide in adults with type 2 diabetes (ACHIEVE-3),” Lancet 407(10534):1147-1160 (2026-02-26 online), PMID 41765029, read via Europe PMC; ClinicalTrials.gov NCT06045221 (read 2026-11-08). https://pubmed.ncbi.nlm.nih.gov/41765029/
6. DailyMed (NLM), Wegovy (semaglutide) injection and tablets prescribing information, revised June 2026 (read 2026-11-08). https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=ee06186f-2aa3-4990-a760-757579d8f77b
7. DailyMed (NLM), Foundayo (orforglipron) prescribing information, revised July 2026 (read 2026-11-08; first 100,000 of 136,652 characters). https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=8ac446c5-feba-474f-a103-23facb9b5c62
8. Eli Lilly and Company, Form 10-Q for the quarter ended 30 September 2026 (2026-10-29), as relied on in our Lilly overview; not re-opened for this article. https://www.sec.gov/Archives/edgar/data/59478/000005947826000108/lly-20260930.htm
9. DailyMed (NLM), Ozempic and Rybelsus (oral semaglutide) tablets prescribing information, label date January 2026 (read 2026-11-08; first 100,000 of 163,240 characters). https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=27f15fac-7d98-4114-a2ec-92494a91da98
10. “Orforglipron … for the treatment of obesity in people with type 2 diabetes (ATTAIN-2),” Lancet 406(10522):2927-2944 (online 2025-11-20), PMID 41275875, read via Europe PMC. https://pubmed.ncbi.nlm.nih.gov/41275875/
11. Knop FK et al., “Oral semaglutide 50 mg taken once per day in adults with overweight or obesity (OASIS 1),” Lancet 402(10403):705-719 (2023), PMID 37385278, read via Europe PMC. https://pubmed.ncbi.nlm.nih.gov/37385278/

This article is information, not medical advice.