PEPVENDORS
Peptides/Semaglutide

For Research Purposes Only. This page summarizes published preclinical and clinical research. It does not constitute medical advice and is not a recommendation for human use. Always consult a qualified healthcare professional.

Metabolic / GLP-1

Semaglutide

GLP-1 receptor agonist. FDA-approved as Ozempic and Wegovy. Among the most extensively studied metabolic compounds in modern pharmacology.

Class
GLP-1 Receptor Agonist
FDA Approvals
Ozempic, Wegovy, Rybelsus
Trial Phase
Phase IV (post-market)
Peak Trial Weight Loss
14.9% (STEP-1, 68 wks)

Overview

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist — a class of compounds that mimic the action of GLP-1, an incretin hormone secreted by intestinal L-cells in response to food intake. GLP-1 receptor activation produces multiple coordinated metabolic effects: it stimulates glucose-dependent insulin secretion from pancreatic beta cells, suppresses glucagon release from alpha cells, slows gastric emptying (reducing post-meal glucose excursions), and activates satiety centers in the hypothalamus via the vagus nerve to reduce appetite. The combination of these mechanisms makes GLP-1 agonists uniquely effective for both glycemic control and weight management.

Semaglutide was originally developed by Novo Nordisk as a once-weekly alternative to daily GLP-1 injections, achieved through a molecular modification that substantially extends its plasma half-life to approximately 7 days. Early clinical development focused on type 2 diabetes, but the STEP trial program (2019–2021) demonstrated unprecedented weight loss effects at higher doses — prompting regulatory approval specifically for obesity management. The STEP-1 trial (New England Journal of Medicine, 2021) demonstrated a mean 14.9% reduction in body weight over 68 weeks in adults with obesity without type 2 diabetes at a dose of 2.4mg/week, establishing a new clinical benchmark. The SELECT trial (NEJM, 2023) subsequently showed a 20% reduction in major adverse cardiovascular events (MACE) in high-risk patients with obesity and established cardiovascular disease, broadening the therapeutic rationale beyond weight management alone.

Semaglutide is FDA-approved under three distinct brand names: Ozempic (once-weekly subcutaneous injection, 0.5–2mg, for type 2 diabetes); Wegovy (once-weekly subcutaneous injection, 2.4mg, for chronic weight management in adults with BMI ≥30 or ≥27 with at least one weight-related comorbidity); and Rybelsus (once-daily oral tablet, for type 2 diabetes). Research-grade semaglutide sold by peptide vendors is a synthetic peptide intended for laboratory research. It is not the pharmaceutical product, is not subject to pharmaceutical-grade manufacturing controls, and is not approved or intended for human use.

Research Status

FDA Status
FDA-approved as Ozempic (type 2 diabetes, 2017), Wegovy (chronic weight management, 2021), and Rybelsus (oral type 2 diabetes, 2019). Research-grade semaglutide sold by peptide vendors is not the pharmaceutical product and is not FDA-approved for human use.
Trial Phase
Phase IV post-market for approved indications. Active trials investigating semaglutide in metabolic dysfunction-associated steatohepatitis (MASH), Alzheimer's disease (EVOKE trial), alcohol use disorder, and sleep apnea.
Key Studies

STEP-1 (Wilding et al., NEJM 2021): 14.9% mean weight reduction at 68 weeks (2.4mg/week). SUSTAIN-6 (Marso et al., NEJM 2016): CV risk reduction established in T2D. SELECT (Lincoff et al., NEJM 2023): 20% MACE reduction in obesity with established CVD. FLOW trial (2024): renal outcomes benefit demonstrated in T2D with chronic kidney disease.

Common Research Protocols

Clinical titration schedule (Wegovy)0.25mg/wk × 4 wks → 0.5 → 1.0 → 1.7 → 2.4mg/wk
Clinical titration schedule (Ozempic)0.25mg/wk × 4 wks → 0.5mg/wk; titrate to 1–2mg/wk as needed
Administration (pharmaceutical)Once-weekly subcutaneous injection (pen device); Rybelsus is oral
Typical research vial sizes2mg, 5mg, 10mg
Reconstitution solventBacteriostatic water; research vials require manual reconstitution unlike pre-filled pharmaceutical pens

Dosing above is from FDA-approved pharmaceutical labeling for Ozempic and Wegovy. These protocols apply to pharmaceutical-grade semaglutide manufactured under GMP conditions. Research-grade vials are not equivalent to pharmaceutical products. This information is for educational reference only.

Use the reconstitution calculator →

Storage & Handling

Lyophilized research semaglutide should be stored at −20°C. Once reconstituted, store at 4°C and use within 28 days. The pharmaceutical pre-filled pens (Ozempic, Wegovy) have different storage requirements and should not be confused with research-grade vials.

What to Look for When Buying

GLP-1 peptides like semaglutide are among the more structurally complex molecules sold by research vendors. Third-party HPLC purity testing is especially critical — impurities in complex peptides can include truncated sequences and synthesis byproducts that are difficult to detect without proper testing.

Finnrick Analytics currently has purity data for semaglutide from several vendors. Their testing includes both purity percentage and quantity accuracy, which matters significantly given that GLP-1 compounds are dosed in small quantities where fill accuracy directly impacts effective dose.

Verify that the vendor's COA specifies HPLC purity, not just mass spectrometry. MS-based identity confirmation tells you that the molecule is present, but not whether it is at the claimed concentration or whether synthesis byproducts are present.

Be aware that research-grade semaglutide from peptide vendors is not subject to the manufacturing controls that apply to Ozempic or Wegovy. It may lack the GMP sterility assurances of pharmaceutical-grade products.

Semaglutide has high search volume and has attracted low-quality vendors. Prioritize vendors with multiple independent Finnrick test results spanning more than one batch.

Compare Vendor Pricing

PepVendors tracks live pricing for Semaglutide across multiple vendors, updated weekly. Compare price per mg, available sizes, and purity data side by side.

Compare Semaglutide prices →

Third-Party Purity Data

Full data at finnrick.com →

Independent HPLC test results from Finnrick Analytics. Purity values are averages across multiple samples. Check the Finnrick vendor page for batch-level detail.

VendorPurity
Simple Peptide
100.0%A
Nuscience Peptides
99.9%A
Peptide Crafters
99.8%A
Liberty Peptides
99.5%A
Paramount Peptides
98.2%A
Coastal Peptides
97.8%B
Pure Rawz
97.5%B
Peptide Sciences
97.5%B
Eternal Peptides
97.2%B
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Legal Disclaimer

For Research Purposes Only — Not Medical Advice. The information on this page is compiled from published peer-reviewed research, publicly available clinical trial data, and independent third-party testing results. It is intended solely as an educational reference for researchers.

Nothing on this page constitutes medical advice, a diagnosis, or a treatment recommendation. Peptides listed as research chemicals are not approved for human consumption unless explicitly noted as FDA-approved pharmaceuticals. PepVendors is a price comparison and information platform — we do not manufacture, sell, or distribute any compounds. Always consult a qualified and licensed healthcare professional before considering any compound for personal use.