GLP-1 Drug Names Decoded: The "-glutide" Suffix and Every Agent Listed
Direct answer: The suffix "-glutide" is the INN (International Nonproprietary Name) stem assigned by the World Health Organization to GLP-1 receptor agonist peptides. Every approved peptide GLP-1 agonist carries it — semaglutide, liraglutide, dulaglutide, exenatide, albiglutide — and so do pipeline peptides like retatrutide. Non-peptide small-molecule GLP-1 agonists (orforglipron) use a different stem convention and do not end in "-glutide."
| Drug name fact | Value |
|---|---|
| INN stem for GLP-1 peptide agonists | -glutide |
| Approved "-glutide" drugs (as of 2026) | 5 (semaglutide, liraglutide, dulaglutide, exenatide, albiglutide) |
| Glutide that starts with "r" (pipeline) | Retatrutide |
| GLP-1 that starts with "r" (on the market) | Rybelsus (oral semaglutide) |
| Non-peptide GLP-1 agonist (no "-glutide") | Orforglipron |
| Dual agonist with "-tide" stem (not "-glutide") | Tirzepatide |
Key Takeaways
- "-glutide" = peptide GLP-1 agonist: The stem is applied by the WHO to identify the drug class. If the generic name ends in -glutide, it activates the GLP-1 receptor as a peptide analogue.
- Retatrutide is the glutide that starts with "r": It is a triple agonist (GLP-1 + GIP + glucagon receptors) in Phase 3 trials. Phase 2 data showed 24.2% weight loss at 48 weeks.
- Tirzepatide does not end in "-glutide": Its stem "-tide" reflects peptide structure but it is classified under a different INN stem because it is a dual agonist — not a pure GLP-1 agent.
- Brand names are separate: Ozempic, Wegovy, Saxenda, Victoza, Mounjaro, Zepbound, and Foundayo are trade names; the generics (semaglutide, liraglutide, tirzepatide, orforglipron) are the INNs.
- Same generic, multiple brands: Semaglutide is sold as Ozempic (diabetes), Wegovy (obesity injectable), and Rybelsus/Wegovy pill (oral) — same molecule, different doses and delivery formats.
Understanding the naming system is the fastest way to decode any GLP-1 drug name you encounter in a prescription, trial paper, or news report. The sections below map the entire class.
The "-glutide" suffix: what it means and why it exists
The International Nonproprietary Name (INN) system, managed by the WHO, assigns standardized stems to drug classes so that a generic name carries structural and mechanistic information. For GLP-1 receptor agonist peptides, the designated stem is -glutide — derived from "glucagon-like peptide."
When a pharmaceutical company develops a new GLP-1 peptide agonist and submits it for INN designation, the WHO appends "-glutide" to a unique prefix chosen for that molecule. The prefix is typically arbitrary (semantic rather than structural), while the suffix is the classification signal. This is why semaglutide, liraglutide, dulaglutide, exenatide, and albiglutide all share the same ending: they are all peptide drugs acting at the GLP-1 receptor.
The stem convention applies specifically to peptide analogues of GLP-1. Non-peptide molecules — small-molecule GLP-1 receptor agonists like orforglipron — do not carry the "-glutide" stem because they belong to a structurally distinct category, even though they activate the same receptor.
Every "-glutide" drug name: the complete list
The following table lists all approved and late-stage pipeline GLP-1 receptor agonist drugs that carry the "-glutide" INN stem, along with their brand names, approval status, and primary indications.
| Generic (INN) | Brand name(s) | Approval status | Primary indication(s) | Subcategory |
|---|---|---|---|---|
| Semaglutide | Ozempic; Wegovy; Rybelsus | FDA approved | T2D; obesity (chronic weight management) | Long-acting GLP-1 agonist |
| Liraglutide | Victoza (1.8mg); Saxenda (3mg) | FDA approved | T2D; obesity | Long-acting GLP-1 agonist |
| Dulaglutide | Trulicity | FDA approved | T2D | Long-acting GLP-1 agonist |
| Exenatide | Byetta (twice daily); Bydureon (weekly) | FDA approved; Bydureon BCise no longer has a current FDA label, and AstraZeneca has filed marketing end dates for Byetta in late 2026 | T2D | Short-acting / extended-release GLP-1 agonist |
| Albiglutide | Tanzeum / Eperzan | Approved (withdrawn from market 2018 for commercial reasons) | T2D | Long-acting GLP-1 agonist |
| Retatrutide | (no brand yet) | Phase 3 — not approved anywhere | Obesity | Triple agonist (GLP-1 + GIP + glucagon) |
| Efpeglenatide | (no brand) | Not approved — Sanofi terminated the Phase 3 AMPLITUDE program in 2020–2021 | T2D | Long-acting GLP-1 agonist |
| Semaglutide (oral 25mg) | Wegovy tablets | FDA approved | Obesity; cardiovascular risk reduction | Oral GLP-1 agonist |
Retatrutide: the glutide that starts with "r"
Retatrutide is the most-searched "-glutide" drug in early-stage queries because it is the only prominent pipeline agent whose name starts with "r." It is developed by Eli Lilly and is currently in Phase 3 clinical trials under the program name TRIUMPH.
Unlike pure GLP-1 agonists, retatrutide is a triple receptor agonist — it activates the GLP-1 receptor, the GIP (glucose-dependent insulinotropic polypeptide) receptor, and the glucagon receptor simultaneously. The glucagon receptor component is what distinguishes it from tirzepatide (GLP-1 + GIP only): glucagon receptor agonism increases energy expenditure and fat oxidation on top of the appetite suppression produced by GLP-1 and GIP activation.
Phase 2 data (published in the New England Journal of Medicine, 2023) showed 24.2% mean body weight loss at 48 weeks at the 12mg dose — the highest figure reported for any GLP-1-class drug at the time of publication. Several TRIUMPH Phase 3 trials finished primary follow-up between November 2025 and June 2026, including TRIUMPH-1 in obesity (NCT05929066) and TRIUMPH-4 in obesity with cardiovascular disease (NCT05882045). Retatrutide still has no FDA approval and no prescribing information on DailyMed as of August 2026, and no regulator anywhere has cleared it.
Retatrutide carries the "-glutide" stem because its primary scaffold is a peptide GLP-1 analogue, even though its pharmacology extends beyond the GLP-1 receptor.
Every GLP-1 drug name that starts with "R"
Two names in the GLP-1 world begin with the letter R, and only one of them is something a pharmacy can actually fill.
| Name starting with "R" | Type of name | What it is | Status (August 2026) |
|---|---|---|---|
| Rybelsus | Brand name | Oral semaglutide tablets — 3mg, 7mg, 14mg once daily | FDA approved for type 2 diabetes; on the US market since 2019 |
| Retatrutide | Generic name (INN) | Eli Lilly's triple agonist, development code LY3437943 | Investigational — Phase 3, no approval in any country |
If the name you are trying to place came off a prescription label, a pharmacy receipt, or an insurance formulary, it is almost certainly Rybelsus — Novo Nordisk's daily semaglutide pill for type 2 diabetes. Note that Novo now sells a second oral semaglutide tablet under the Ozempic name at 1.5mg, 4mg and 9mg strengths. The FDA label covering both states plainly that Rybelsus and Ozempic tablets "are not substitutable on a mg-to-mg basis," so the milligram number on the bottle only means something alongside the brand. If that is the name on your bottle, our Rybelsus coupon guide covers what the tablets cost.
If the name came from trial coverage, a weight-loss forum, or a research-chemical vendor, it is retatrutide — usually shortened to "reta" in community posts. It is not an approved medicine, so nothing sold under that name online is FDA-regulated, quality-controlled, or legal to sell for human use.
No other GLP-1 receptor agonist starts with R. Not the generic names — exenatide, liraglutide, dulaglutide, semaglutide, lixisenatide, albiglutide, tirzepatide, orforglipron — and not the brands: Byetta, Victoza, Saxenda, Trulicity, Ozempic, Wegovy, Mounjaro, Zepbound, Foundayo and Soliqua.
GLP-1 drug names that do NOT end in "-glutide"
Two significant agents in the broader GLP-1 drug landscape do not carry the "-glutide" stem, for different structural reasons.
Tirzepatide (Mounjaro / Zepbound)
Tirzepatide ends in "-tide" — the generic INN stem for peptides — rather than "-glutide." This is because tirzepatide is classified as a dual GIP/GLP-1 receptor agonist, not a pure GLP-1 agonist. The WHO assigned it a different stem to reflect its co-primary GIP mechanism. Functionally it activates the GLP-1 receptor, so it is clinically grouped with GLP-1 receptor agonists — but its naming follows the dual-agonist classification.
Tirzepatide (Zepbound for obesity; Mounjaro for T2D) showed 22.5% mean body weight loss at 72 weeks in the SURMOUNT-1 trial at the 15mg dose, making it the highest-efficacy approved agent in the class.
Orforglipron (Foundayo)
Orforglipron is a non-peptide, small-molecule GLP-1 receptor agonist — it activates the GLP-1 receptor without being a peptide analogue of GLP-1. Because the "-glutide" stem applies specifically to peptide GLP-1 analogues, orforglipron received a different INN designation. Its name ends in "-glipron," which the WHO uses for this structural subcategory.
Orforglipron is sold as Foundayo, and its FDA label lists an initial U.S. approval of 2026; the first NDC listings went live on April 1, 2026. It can be taken orally with or without food — no fasting window required — because it has no peptide backbone to be digested. It is approved for weight management only: the label indication is adults with obesity, or adults with overweight plus at least one weight-related comorbidity. It does not carry a type 2 diabetes indication.
Tablets come in 0.8mg, 2.5mg, 5.5mg, 9mg, 14.5mg and 17.2mg, titrated no faster than one step every 30 days. In the two 72-week trials in the label, mean weight change at the top 17.2mg dose was -11.1% versus -2.1% on placebo in participants without diabetes (NCT05869903), and -9.6% versus -2.5% in participants with type 2 diabetes (NCT05872620). Like the injectable agents, it carries a boxed warning for thyroid C-cell tumors.
Brand vs. generic names: a complete mapping
The same generic drug often has multiple brand names at different doses or for different indications. The table below maps every major brand name to its generic.
| Brand name | Generic (INN) | Dose / format | Approved indication |
|---|---|---|---|
| Ozempic | Semaglutide | 0.5mg, 1mg, 2mg — subcutaneous weekly | Type 2 diabetes |
| Wegovy | Semaglutide | 2.4mg (up to 7.2mg) — subcutaneous weekly | Obesity / chronic weight management; cardiovascular risk reduction; MASH with fibrosis |
| Rybelsus | Semaglutide | 3mg, 7mg, 14mg — oral daily | Type 2 diabetes |
| Ozempic (tablets) | Semaglutide | 1.5mg, 4mg, 9mg — oral daily | Type 2 diabetes |
| Wegovy (tablets) | Semaglutide | 25mg — oral daily | Obesity / chronic weight management; cardiovascular risk reduction |
| Victoza | Liraglutide | 1.2mg, 1.8mg — subcutaneous daily | Type 2 diabetes |
| Saxenda | Liraglutide | 3mg — subcutaneous daily | Obesity / chronic weight management |
| Trulicity | Dulaglutide | 0.75mg, 1.5mg, 3mg, 4.5mg — subcutaneous weekly | Type 2 diabetes |
| Byetta | Exenatide | 5mcg, 10mcg — subcutaneous twice daily | Type 2 diabetes |
| Bydureon / Bydureon BCise | Exenatide extended-release | 2mg — subcutaneous weekly | Type 2 diabetes |
| Mounjaro | Tirzepatide | 2.5–15mg — subcutaneous weekly | Type 2 diabetes |
| Zepbound | Tirzepatide | 2.5–15mg — subcutaneous weekly | Obesity / chronic weight management; moderate-to-severe obstructive sleep apnea |
| Foundayo | Orforglipron | 0.8–17.2mg — oral daily | Obesity / chronic weight management |
Key naming conventions to remember
- Same generic = same molecule. Ozempic and Wegovy are both semaglutide. The brand name signals dose and indication, not a different drug.
- Higher dose does not always equal a different brand. Semaglutide 2mg (Ozempic) and semaglutide 2.4mg (Wegovy) are the same molecule at slightly different doses under different brand names for different indications.
- Generic names are stable; brand names change. If a drug loses patent protection and generics enter the market, the INN (semaglutide, liraglutide, etc.) is what persists.
Full efficacy and classification comparison
| Generic (INN) | Brand | Route | Frequency | Receptor target(s) | Weight loss (key trial) | Stem |
|---|---|---|---|---|---|---|
| Exenatide | Byetta / Bydureon | Subcutaneous | Twice daily / weekly | GLP-1R | ~2–3 kg | -glutide |
| Liraglutide | Victoza / Saxenda | Subcutaneous | Daily | GLP-1R | ~8% at 56 wks (SCALE) | -glutide |
| Dulaglutide | Trulicity | Subcutaneous | Weekly | GLP-1R | ~3–5 kg | -glutide |
| Semaglutide | Ozempic / Wegovy / Rybelsus | Subcutaneous / Oral | Weekly / Daily | GLP-1R | ~15% at 68 wks (STEP 1) | -glutide |
| Tirzepatide | Mounjaro / Zepbound | Subcutaneous | Weekly | GLP-1R + GIPR | 22.5% at 72 wks (SURMOUNT-1) | -tide |
| Orforglipron | Foundayo | Oral | Daily | GLP-1R | 11.1% at 72 wks (17.2mg, label trial NCT05869903) | -glipron |
| Retatrutide | (pipeline) | Subcutaneous | Weekly | GLP-1R + GIPR + GCGR | 24.2% at 48 wks (Phase 2) | -glutide |
How GLP-1 drug naming works in practice
When you see a drug name ending in "-glutide," you can immediately conclude:
- It is a peptide analogue of GLP-1.
- It is a GLP-1 receptor agonist — it activates the receptor that GLP-1 naturally activates.
- It requires injection in almost all cases (peptides are digested orally unless special delivery technology is used, as with oral semaglutide).
When you see a drug that activates the GLP-1 receptor but does NOT end in "-glutide" (tirzepatide, orforglipron, retatrutide excluded from this rule since it does end in -glutide), the drug is either a dual/triple agonist (tirzepatide) or a small-molecule non-peptide (orforglipron).
This naming structure is consistent and reliable — it is the same framework used in clinical literature, prescribing information, and regulatory filings worldwide.
Frequently Asked Questions
What does "-glutide" mean in drug names? It is the WHO INN stem for GLP-1 receptor agonist peptides. All peptide GLP-1 agonists have an INN ending in -glutide: semaglutide, liraglutide, dulaglutide, exenatide, albiglutide, retatrutide.
What is the glutide that starts with "r"? Retatrutide. It is a triple agonist (GLP-1 + GIP + glucagon receptors) developed by Eli Lilly, currently in Phase 3 trials. Phase 2 data showed 24.2% weight loss at 48 weeks — the highest figure published for any GLP-1-class agent to date.
Which GLP-1 drug starts with the letter R? Two names qualify, and they are not equivalent. Rybelsus is a real, FDA-approved, on-the-shelf product: oral semaglutide tablets at 3mg, 7mg or 14mg once daily for type 2 diabetes. Retatrutide is Eli Lilly's investigational triple agonist — Phase 3, no approval anywhere, no FDA label. If a pharmacist dispensed it to you, it was Rybelsus. If you read about it in trial coverage or on a forum, it was retatrutide.
Why doesn't tirzepatide end in "-glutide"? Tirzepatide is a dual GIP/GLP-1 receptor agonist — its primary INN classification is as a dual agonist peptide, not a pure GLP-1 analogue. The WHO assigned it the "-tide" stem (generic peptide) rather than "-glutide" (GLP-1 peptide). It still acts on the GLP-1 receptor and is grouped clinically with GLP-1 RAs.
Are Ozempic and semaglutide the same drug? Yes. Ozempic is the brand name; semaglutide is the generic (INN). Wegovy is also semaglutide — the same molecule at a higher dose (2.4mg vs. 1–2mg) with an obesity indication.
Is there a GLP-1 drug that does not require injection? Yes, three: oral semaglutide for diabetes (Rybelsus 3/7/14mg, and Ozempic tablets at 1.5/4/9mg), oral semaglutide for obesity (Wegovy tablets, 25mg daily), and orforglipron (Foundayo). Every semaglutide tablet has to be swallowed on an empty stomach with no more than 4 ounces of water, followed by a 30-minute wait before food, drink or other oral medication. Orforglipron can be taken with or without food, which is its main practical advantage.
Are all "-glutide" drugs approved for weight loss? No. Only specific agents at specific doses carry an FDA obesity indication: semaglutide 2.4mg injection (Wegovy), liraglutide 3mg (Saxenda), and semaglutide 25mg tablets (Wegovy tablets). Dulaglutide and exenatide are approved for type 2 diabetes only. Tirzepatide (Zepbound) and orforglipron (Foundayo) are also approved for obesity but do not carry the "-glutide" stem.
What GLP-1 drugs are in the pipeline? Retatrutide (Eli Lilly, Phase 3) is the most advanced pipeline "-glutide" agent, with several TRIUMPH trials completed in 2025–2026 and no approval yet. Several other triple agonists and next-generation peptides are in Phase 1 and 2 development.
This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider before starting any medication.
References
- Jastreboff AM, Kaplan LM, Frías JP, et al. Triple–Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial. New England Journal of Medicine. 2023. PubMed
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). New England Journal of Medicine. 2022. PubMed
- Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). New England Journal of Medicine. 2021. PubMed
- Pi-Sunyer X, Astrup A, Fujioka K, et al. A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management (SCALE). New England Journal of Medicine. 2015. PubMed
- Eli Lilly and Company. FOUNDAYO (orforglipron) tablets — full prescribing information. Initial U.S. Approval 2026. DailyMed
- Novo Nordisk. WEGOVY (semaglutide) injection and tablets — full prescribing information. DailyMed
- Novo Nordisk. OZEMPIC (oral semaglutide) tablets / RYBELSUS (oral semaglutide) tablets — full prescribing information. DailyMed
- Eli Lilly and Company. ZEPBOUND (tirzepatide) injection — full prescribing information. DailyMed
- U.S. National Library of Medicine. Retatrutide (LY3437943) study records — TRIUMPH Phase 3 program. ClinicalTrials.gov
