The 6 FDA-Approved GLP-1 Receptor Agonists: A Complete Guide

GLP-1 receptor agonists have become one of the most consequential drug classes in modern medicine — transforming the treatment of type 2 diabetes, obesity, and cardiovascular disease simultaneously. Six distinct GLP-1 drugs are currently FDA-approved in the United States, ranging from the original twice-daily injection (exenatide) to the first oral GLP-1 pill (oral semaglutide). Each has a distinct profile of efficacy, dosing, side effects, and cost.

This guide covers every approved GLP-1 drug in clinical depth, including head-to-head comparison data where available.

What Is a GLP-1 Receptor Agonist?

Glucagon-like peptide-1 (GLP-1) is a hormone produced by L-cells in the small intestine in response to food intake. It acts on multiple organ systems:

• Pancreas: Stimulates insulin secretion in a glucose-dependent manner (only when blood sugar is elevated) and suppresses glucagon release
• Stomach: Slows gastric emptying, prolonging the feeling of fullness after meals
• Brain: Acts on hypothalamic appetite centers to reduce hunger and increase satiety
• Heart: Has direct cardioprotective effects independent of glucose lowering
• Liver: Reduces hepatic glucose production

GLP-1 receptor agonists (GLP-1 RAs) are synthetic peptides that mimic or enhance these effects. Because their insulin-stimulating effect is glucose-dependent, they carry a very low risk of hypoglycemia — a significant advantage over sulfonylureas and insulin.

The 6 FDA-Approved GLP-1 Drugs

1. Exenatide (Byetta, Bydureon BCise)

Manufacturer: AstraZeneca
FDA Approval: 2005 (Byetta); 2012 (Bydureon extended-release)
Indication: Type 2 diabetes (adjunct to diet and exercise)
Dosing: Byetta: 5–10 mcg twice daily (injected within 60 minutes before meals); Bydureon BCise: 2 mg once weekly

Exenatide was the first GLP-1 receptor agonist approved in the United States and was derived from exendin-4, a peptide found in the saliva of the Gila monster lizard. It shares approximately 53% amino acid sequence homology with human GLP-1.

Efficacy: In the DURATION trials, exenatide once weekly reduced HbA1c by approximately 1.3–1.6% and produced modest weight loss of 2–3 kg. It is less potent than semaglutide or tirzepatide in both glycemic and weight outcomes.

Cardiovascular data: The EXSCEL trial (14,752 patients) showed exenatide once weekly was non-inferior to placebo for MACE (major adverse cardiovascular events) but did not demonstrate superiority. It does not carry a cardiovascular risk reduction indication.

Key limitation: Exenatide is the only GLP-1 RA that is not human GLP-1 analog — it is derived from a lizard peptide. This means it can trigger anti-drug antibodies in some patients, potentially reducing efficacy over time. It also has the highest injection frequency among the once-weekly options.

Typical monthly cost: ~$400–$600 (Bydureon BCise)

2. Liraglutide (Victoza, Saxenda)

Manufacturer: Novo Nordisk
FDA Approval: 2010 (Victoza for diabetes); 2014 (Saxenda for obesity)
Indication: Victoza: Type 2 diabetes + cardiovascular risk reduction; Saxenda: Chronic weight management
Dosing: Victoza: 0.6 mg → 1.2 mg → 1.8 mg once daily; Saxenda: 0.6 mg → 3.0 mg once daily (titrated over 5 weeks)

Liraglutide is a human GLP-1 analog with 97% sequence homology to native GLP-1, modified with a fatty acid chain that extends its half-life to approximately 13 hours (enabling once-daily dosing).

Efficacy (diabetes): In the LEADER trial, liraglutide reduced HbA1c by approximately 1.0–1.5% and produced weight loss of approximately 3–4 kg at the 1.8 mg dose.

Efficacy (weight loss): In the SCALE Obesity trial, liraglutide 3.0 mg produced average weight loss of 8.0% of body weight at 56 weeks — significantly more than placebo (2.6%) but substantially less than semaglutide 2.4 mg (~15%).

Cardiovascular data: The LEADER trial (9,340 patients with type 2 diabetes and high cardiovascular risk) demonstrated that liraglutide significantly reduced MACE by 13% compared to placebo. This was the first GLP-1 RA to demonstrate cardiovascular superiority and established the class's cardiovascular benefits.

Key advantage: Liraglutide has the longest real-world safety track record of any GLP-1 RA, with over 15 years of post-marketing data. It is also available in a pediatric formulation (Victoza is approved for type 2 diabetes in children ≥10 years; Saxenda is approved for obesity in adolescents ≥12 years).

Typical monthly cost: Victoza ~$590; Saxenda ~$1,350

3. Dulaglutide (Trulicity)

Manufacturer: Eli Lilly
FDA Approval: 2014
Indication: Type 2 diabetes + cardiovascular risk reduction
Dosing: 0.75 mg or 1.5 mg once weekly (higher doses of 3 mg and 4.5 mg also approved)

Dulaglutide is a once-weekly GLP-1 RA with a unique structure — it is a fusion protein consisting of two modified GLP-1 molecules linked to an IgG4 Fc fragment, which extends its half-life to approximately 5 days.

Efficacy: In the AWARD trials, dulaglutide 1.5 mg reduced HbA1c by approximately 1.1–1.6%. Weight loss is modest at approximately 2–3 kg at the standard 1.5 mg dose, though higher doses (3 mg, 4.5 mg) produce greater weight loss.

Cardiovascular data: The REWIND trial (9,901 patients with type 2 diabetes) demonstrated that dulaglutide significantly reduced MACE by 12% compared to placebo, including a significant reduction in stroke — the only GLP-1 RA with a specific stroke reduction signal in its pivotal trial.

Key advantage: Trulicity's autoinjector pen is widely regarded as the easiest to use in the GLP-1 class — it requires no assembly, no needle attachment, and no dose dialing. The needle is hidden, which is helpful for needle-averse patients. This has contributed to Trulicity becoming one of the highest-prescribed GLP-1 drugs despite not being the most potent.

Typical monthly cost: ~$870

4. Semaglutide Injection (Ozempic, Wegovy)

Manufacturer: Novo Nordisk
FDA Approval: 2017 (Ozempic for diabetes); 2021 (Wegovy for obesity); 2024 (Wegovy cardiovascular indication)
Indication: Ozempic: Type 2 diabetes + cardiovascular risk reduction; Wegovy: Chronic weight management + cardiovascular risk reduction
Dosing: Ozempic: 0.25 mg → 0.5 mg → 1 mg → 2 mg once weekly; Wegovy: 0.25 mg → 0.5 mg → 1 mg → 1.7 mg → 2.4 mg once weekly

Semaglutide is a human GLP-1 analog with 94% sequence homology to native GLP-1, modified with two structural changes that extend its half-life to approximately 7 days (enabling once-weekly dosing) and increase albumin binding (reducing renal clearance).

Efficacy (diabetes): In the SUSTAIN trials, semaglutide 1 mg reduced HbA1c by approximately 1.5–1.8% — the most potent glycemic effect among the once-weekly GLP-1 RAs. Weight loss at 1 mg was approximately 4–6 kg.

Efficacy (weight loss): In the STEP 1 trial, semaglutide 2.4 mg produced average weight loss of 14.9% of body weight at 68 weeks — the most effective non-surgical weight loss intervention ever studied in a large randomized trial at the time of its approval.

Cardiovascular data: The SUSTAIN-6 trial demonstrated cardiovascular non-inferiority. The SELECT trial (17,604 patients with obesity or overweight and established cardiovascular disease, without diabetes) demonstrated a 20% relative risk reduction in MACE — the first GLP-1 RA to demonstrate cardiovascular benefit in a non-diabetic population.

Key advantage: Semaglutide is the most potent GLP-1 RA currently available in injectable form, with the strongest evidence base for both glycemic control and weight loss. The SELECT trial result also makes it the only GLP-1 RA approved for cardiovascular risk reduction in non-diabetic patients with obesity.

Typical monthly cost: Ozempic ~$935; Wegovy ~$1,350

5. Oral Semaglutide (Rybelsus)

Manufacturer: Novo Nordisk
FDA Approval: 2019
Indication: Type 2 diabetes
Dosing: 3 mg → 7 mg → 14 mg once daily (taken on empty stomach with ≤4 oz water, 30 minutes before first food/drink/medication)

Rybelsus is the first and only oral GLP-1 receptor agonist. It contains the same semaglutide molecule as Ozempic but formulated with SNAC (sodium N-[8-(2-hydroxybenzoyl) amino] caprylate), an absorption enhancer that enables the peptide to survive the acidic stomach environment and be absorbed through the gastric mucosa.

Efficacy: In the PIONEER trials, oral semaglutide 14 mg reduced HbA1c by approximately 1.2–1.4% and produced weight loss of approximately 3–4 kg — somewhat less than injectable semaglutide 1 mg, reflecting lower bioavailability of the oral formulation (~1% vs. ~89% for subcutaneous injection).

Key advantage: Oral administration eliminates injection anxiety entirely, which is a significant barrier for many patients. For patients with needle phobia or strong preference for oral medications, Rybelsus provides GLP-1 class benefits without injections.

Key limitation: The strict administration requirements (empty stomach, ≤4 oz water, 30-minute wait) are challenging for many patients and reduce real-world adherence. Food, other medications, and even excess water significantly reduce absorption.

Typical monthly cost: ~$935

6. Tirzepatide (Mounjaro, Zepbound)

Manufacturer: Eli Lilly
FDA Approval: 2022 (Mounjaro for diabetes); 2023 (Zepbound for obesity)
Indication: Mounjaro: Type 2 diabetes; Zepbound: Chronic weight management
Dosing: 2.5 mg → 5 mg → 7.5 mg → 10 mg → 12.5 mg → 15 mg once weekly

Tirzepatide is technically a dual GIP/GLP-1 receptor agonist — it activates both the GLP-1 receptor and the glucose-dependent insulinotropic polypeptide (GIP) receptor. GIP is another incretin hormone that potentiates insulin secretion and may enhance the weight loss effects of GLP-1 receptor activation. Some researchers classify tirzepatide as a "twincretin" rather than a pure GLP-1 RA.

Efficacy (diabetes): In the SURPASS trials, tirzepatide 15 mg reduced HbA1c by approximately 2.0–2.3% — the most potent glycemic effect of any approved non-insulin diabetes drug. In the SURPASS-2 trial, tirzepatide 15 mg reduced HbA1c by 2.46% vs. 1.86% for semaglutide 1 mg.

Efficacy (weight loss): In the SURMOUNT-1 trial, tirzepatide 15 mg produced average weight loss of 20.9% of body weight at 72 weeks — surpassing semaglutide 2.4 mg's 14.9% in the STEP 1 trial. Approximately 57% of patients achieved ≥20% weight loss with tirzepatide 15 mg.

Cardiovascular data: The SURPASS-CVOT trial is ongoing. Tirzepatide does not yet have a cardiovascular risk reduction indication, though the SURMOUNT-MMO trial is evaluating cardiovascular outcomes in patients with obesity.

Key advantage: Tirzepatide produces the greatest weight loss of any approved medication — approaching the results seen with bariatric surgery in some patients. Its dual mechanism may explain the superior efficacy compared to pure GLP-1 RAs.

Typical monthly cost: Mounjaro ~$1,060; Zepbound ~$1,060

Head-to-Head Comparison

Which GLP-1 Drug Is Right for You?

The choice among GLP-1 drugs depends on several factors:

Primary goal is glycemic control: Tirzepatide (Mounjaro) or semaglutide (Ozempic) offer the strongest HbA1c reduction. Tirzepatide is superior in head-to-head trials.

Primary goal is weight loss: Tirzepatide (Zepbound) produces the greatest average weight loss (~21% at maximum dose). Semaglutide 2.4 mg (Wegovy) is the second most effective (~15%).

Needle phobia: Oral semaglutide (Rybelsus) is the only non-injectable option, though it requires strict administration conditions and produces somewhat less weight loss.

Cardiovascular risk reduction: Semaglutide (Ozempic/Wegovy) has the broadest cardiovascular indication, including non-diabetic patients with obesity. Liraglutide and dulaglutide have cardiovascular indications in diabetic patients only.

Ease of use: Dulaglutide (Trulicity) has the most user-friendly autoinjector. Semaglutide (Ozempic) pens are also well-designed.

Cost: Liraglutide (Victoza) and dulaglutide (Trulicity) are generally less expensive than semaglutide or tirzepatide. For patients without insurance coverage, cost is often the primary driver of drug selection.

For detailed drug information, dosing guides, and cost comparisons, see the individual drug pages on RxGuide: Semaglutide, Tirzepatide, Liraglutide, Dulaglutide, Exenatide, Oral Semaglutide.

Sources

1. FDA. Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book). 2026. https://www.accessdata.fda.gov/scripts/cder/ob/
2. Marso SP, et al. Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes (LEADER). N Engl J Med. 2016;375:311-322.
3. Gerstein HC, et al. Dulaglutide and Cardiovascular Outcomes in Type 2 Diabetes (REWIND). Lancet. 2019;394:121-130.
4. Marso SP, et al. Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes (SUSTAIN-6). N Engl J Med. 2016;375:1834-1844.
5. Lincoff AM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (SELECT). N Engl J Med. 2023;389:2221-2232.
6. Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). N Engl J Med. 2022;387:205-216.
7. Frías JP, et al. Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2). N Engl J Med. 2021;385:503-515.
8. Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med. 2021;384:989-1002.