peptides vs ozempic: GLP-1 comparison tool
compare GLP-1 receptor agonists side by side. semaglutide vs tirzepatide vs liraglutide -- evidence tiers, weight loss data, costs, and emerging research.
important medical disclaimer. this tool compares FDA-approved prescription medications and research compounds. it is for educational purposes only and is not medical advice, a recommendation, or a substitute for professional healthcare guidance. GLP-1 receptor agonists are prescription drugs with significant side effects. always consult a licensed physician before starting, stopping, or changing any medication.
the GLP-1 landscape in 2026
GLP-1 receptor agonists have transformed weight management and metabolic medicine. what started as diabetes drugs -- liraglutide (Victoza, 2010) and semaglutide (Ozempic, 2017) -- has become the fastest-growing drug class in pharmaceutical history. the approvals of Wegovy (2021) and tirzepatide (Mounjaro, 2022; Zepbound, 2023) for chronic weight management opened a new era of incretin-based obesity treatment.
the core mechanism is straightforward: GLP-1 (glucagon-like peptide-1) is a natural hormone released by your gut after eating. it signals satiety to the brain, slows gastric emptying, and improves insulin sensitivity. synthetic GLP-1 receptor agonists amplify and extend this signal far beyond what endogenous GLP-1 achieves, because natural GLP-1 has a half-life of just 2 minutes.
but not all GLP-1 drugs are equal. they differ in mechanism (single vs dual vs triple agonist), route of administration (injection vs oral), dosing frequency (daily vs weekly), weight loss efficacy, side effect profiles, cardiovascular data, and cost. this tool helps you compare them objectively using data from major clinical trials.
FDA-approved vs research-only
three GLP-1 agonists are currently FDA-approved for weight management: semaglutide (Wegovy, injectable), liraglutide (Saxenda), and tirzepatide (Zepbound). oral semaglutide (Rybelsus) is approved for type 2 diabetes but not yet for weight management specifically. retatrutide, a triple-agonist, is in phase 3 trials with the highest weight loss data seen in any clinical program to date.
compounded versions of semaglutide and tirzepatide are also available through compounding pharmacies, typically at lower cost. however, the FDA has raised concerns about quality variability in compounded formulations. if considering compounded GLP-1 peptides, verify the pharmacy's 503B registration and request a Certificate of Analysis -- our safety checker tool can help evaluate supplier quality.
how to use this tool
select 2-3 GLP-1 peptides below to generate a side-by-side comparison. the tool shows:
- comparison cards -- mechanism, evidence tier, FDA status, weight loss data, dosing, cost, pros, cons, and side effects
- bar chart -- average weight loss percentage from pivotal clinical trials
- radar chart -- multi-dimensional comparison across efficacy, evidence quality, convenience, tolerability, cost, and cardiovascular data
- emerging research -- next-generation compounds including BRP (Stanford's natural peptide), survodutide, orforglipron, and amycretin
understanding the data
weight loss percentages shown are averages from the highest-dose arms of pivotal phase 3 (or phase 2 for retatrutide) clinical trials. individual results vary significantly based on genetics, diet, exercise, adherence, and starting weight. clinical trials also include structured lifestyle interventions (diet counseling, exercise recommendations) that contribute to outcomes.
the radar chart scores are derived from published trial data and clinical guidelines. "cardiovascular data" reflects whether the compound has dedicated cardiovascular outcomes trial (CVOT) data showing benefit. semaglutide scored highest here due to the SELECT trial demonstrating a 20% reduction in major cardiovascular events. tirzepatide's SURPASS-CVOT is ongoing.
cost ranges reflect approximate US cash prices without insurance as of early 2026. prices vary significantly by pharmacy, manufacturer coupons, and insurance coverage. retatrutide is listed as "not yet available" because it has not received FDA approval.
frequently asked questions about GLP-1 peptides
in clinical trials, tirzepatide (Mounjaro/Zepbound) has shown higher average weight loss than semaglutide (Ozempic/Wegovy). SURMOUNT-1 reported up to 22.5% body weight reduction with tirzepatide versus approximately 15% with semaglutide in STEP trials. however, semaglutide has more long-term safety data and proven cardiovascular benefit from the SELECT trial. the "better" option depends on individual health profile, insurance coverage, and prescriber assessment.
retatrutide is a triple-agonist peptide from Eli Lilly that simultaneously activates GIP, GLP-1, and glucagon receptors. the addition of glucagon receptor activation increases energy expenditure and hepatic fat oxidation beyond what dual agonists like tirzepatide achieve. in phase 2 trials, it showed up to 24.2% weight loss at 48 weeks. phase 3 trials are ongoing and it is not yet FDA-approved.
compounded semaglutide and tirzepatide are prepared by compounding pharmacies, typically during brand-name supply shortages. the FDA has expressed concerns about quality control, as compounded formulations do not undergo the same manufacturing standards and FDA review as brand-name drugs. if using compounded GLP-1 peptides, verify the pharmacy is 503B-registered, request a Certificate of Analysis (COA) with third-party purity testing, and ensure your physician is involved in prescribing and monitoring.
oral semaglutide (Rybelsus) is currently the only FDA-approved oral GLP-1 option. it uses a SNAC absorption enhancer and must be taken on an empty stomach with minimal water, 30 minutes before food. its weight loss efficacy (~7%) is lower than injectable semaglutide (~15%). orforglipron, a non-peptide oral GLP-1 agonist from Eli Lilly, is in phase 3 trials and showed 14.7% weight loss in phase 2 without the strict dosing restrictions.
BRP (body regulating peptide) is a naturally occurring 12-amino-acid peptide discovered by Stanford researchers. unlike synthetic GLP-1 agonists, BRP appears to regulate body weight through a novel, GLP-1-independent pathway. in mouse studies, it reduced body weight without the nausea and GI side effects common to GLP-1 drugs. it is still in very early preclinical research and is not available as a treatment.
brand-name semaglutide (Ozempic for diabetes, Wegovy for weight management) costs approximately $900-1,350 per month without insurance in the US. tirzepatide (Mounjaro/Zepbound) is similarly priced at $1,000-1,100 per month. liraglutide (Saxenda) can be $1,200-1,400 per month. manufacturer savings programs, GoodRx coupons, and insurance formulary coverage can significantly reduce out-of-pocket costs. compounded versions may be cheaper but quality varies.
references
- Wilding JPH, et al. "Once-weekly semaglutide in adults with overweight or obesity." N Engl J Med. 2021;384(11):989-1002. (STEP 1)
- Jastreboff AM, et al. "Tirzepatide once weekly for the treatment of obesity." N Engl J Med. 2022;387(3):205-216. (SURMOUNT-1)
- Pi-Sunyer X, et al. "A randomized, controlled trial of 3.0 mg of liraglutide in weight management." N Engl J Med. 2015;373(1):11-22. (SCALE)
- Jastreboff AM, et al. "Triple-hormone-receptor agonist retatrutide for obesity -- a phase 2 trial." N Engl J Med. 2023;389(6):514-526.
- Lincoff AM, et al. "Semaglutide and cardiovascular outcomes in obesity without diabetes." N Engl J Med. 2023;389(24):2221-2232. (SELECT)
- Aroda VR, et al. "PIONEER 1: randomized clinical trial of the efficacy and safety of oral semaglutide." Diabetes Care. 2019;42(9):1724-1732.
- Frias JP, et al. "Tirzepatide versus semaglutide once weekly in patients with type 2 diabetes." N Engl J Med. 2021;385(6):503-515. (SURPASS-2)
- Marso SP, et al. "Liraglutide and cardiovascular outcomes in type 2 diabetes." N Engl J Med. 2016;375(4):311-322. (LEADER)
- Stanford University. "Researchers discover natural peptide that regulates body weight." Stanford Medicine News. 2024.
- Wharton S, et al. "Daily oral GLP-1 receptor agonist orforglipron for adults with obesity." N Engl J Med. 2023;389(10):877-888.
- Knop FK, et al. "Oral semaglutide 50 mg taken once daily in adults with overweight or obesity (OASIS 1)." Lancet. 2023;402(10403):705-719.
- Sattar N, et al. "Tirzepatide cardiovascular event risk assessment: a pre-specified meta-analysis." Nat Med. 2022;28(3):591-598.
dive deep on GLP-1 agonists
this comparison gives you the overview. our courses cover full mechanism of action, clinical trial data, dosing protocols, risk profiles, and research sources for each peptide.