Semaglutide: The Strongest Evidence Base in Peptides — and the Riskiest Grey Market
Semaglutide has more high-quality human evidence behind it than anything else in this library. That also makes it the most counterfeited compound in the research supply chain, because demand vastly outstrips the licensed pathway.
5mg
Typical vial
$54
Lowest tracked
$96
Median price
161
Vendors listing
What the clinical record shows
Semaglutide is a GLP-1 receptor agonist with a very large randomised trial record covering glycaemic control, body weight, and cardiovascular endpoints. Our index tracks roughly 940 referencing studies.
This is the only evidence grade of Strong in our metabolic category that rests almost entirely on large multi-centre human trials rather than extrapolated animal work.
Why the research market is different here
Licensed semaglutide is a prescription medicine. Anything sold as a research chemical sits entirely outside that framework, with no pharmacovigilance and no regulated manufacturing standard.
Analytical testing has repeatedly found under-dosed, mislabelled, and adulterated material in grey-market GLP-1 supply. Certificate coverage matters more here than anywhere else in the index.
Pricing signals
Tracked 5mg vials range from about £43 to £76. Extremely cheap listings are the strongest single predictor of under-dosed material in our pricing data.
Sudden price drops across a vendor's whole GLP-1 range, without a matching change in test coverage, is a pattern we flag in scoring.
Reading a semaglutide certificate
Look for identity confirmation by mass spectrometry, purity by HPLC, and — ideally — a quantitative content assay rather than purity alone. Purity tells you what fraction of the peptide present is correct; it does not tell you how much peptide is in the vial.
Vendors publishing content assays alongside purity score materially higher in our model.
Frequently asked
Is research-grade semaglutide the same as the prescription product?
No. Licensed products are manufactured to pharmaceutical standards with regulatory oversight. Research-grade material carries none of those guarantees.
What does a purity result not tell me?
It does not tell you the quantity in the vial. Ask for a content or assay result as well.
Search focus for this profile
semaglutide — 368,000/mo searches, difficulty 89/100 — very hard. Source: Semrush (UK database).
Supporting terms covered: semaglutide research peptide, semaglutide purity testing, compounded semaglutide risks.
Everything below describes published research and market data. Nothing here is medical advice, and none of these compounds are sold or supplied by CheckALab.
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