Category · 9 peptides
GLP-1 & metabolic peptides
The most-studied, most-prescribed category here — and the one with the most counterfeits. Pep separates the approved from the gray-market.
Some are genuinely proven
Semaglutide and tirzepatide have large human trials and regulatory approval for their on-label uses.
Newer ≠ better-evidenced
Retatrutide and cagrilintide look strong but are still in trials, not approved.
Sourcing is the real risk
Gray-market vials are where the danger is — not the molecule itself.
Every GLP-1 peptide we've ruled on
See all categories →Amycretin is Novo Nordisk's investigational unimolecular GLP-1 and amylin receptor agonist, studied in both oral and injectable forms for metabolic endpoints. It is early-stage and not approved or available for human use.
AI-discovered 12-amino-acid peptide commonly researched for appetite — striking animal data, zero human trials, not available for human use.
Cagrilintide is a long-acting amylin-analog peptide commonly researched for appetite and body-weight endpoints, most visibly as the amylin half of the investigational CagriSema combination with semaglutide. It is not FDA-approved; effects in humans are still being studied.
Mazdutide (IBI362, LY3305677) is a glucagon/GLP-1 dual-agonist peptide commonly researched for weight management and metabolic outcomes. It has genuine human trial data and was approved by China's regulator for chronic weight management, but it is not FDA-approved in the United States; research-grade mazdutide sold for lab use is for laboratory research only.
Investigational GLP-1/glucagon dual agonist from Altimmune, studied in early trials for obesity and MASH.
Retatrutide (LY3437943) is an experimental triple-agonist peptide commonly researched for weight management and metabolic outcomes. It has genuine human trial data behind it, but it is still investigational and is not FDA-approved; research-grade retatrutide is sold for laboratory research use only.
Investigational GLP-1/glucagon dual agonist posting notable weight and liver numbers in trials — not approved or available.
Tirzepatide is a dual GIP/GLP-1 receptor agonist commonly researched for weight and blood-sugar outcomes. The branded prescription versions, Mounjaro and Zepbound, are FDA-approved for narrow indications; research-grade tirzepatide sold for lab use is not those products and is not FDA-approved.
VK2735 is Viking Therapeutics' investigational dual GLP-1/GIP receptor peptide, developed in both injectable and oral tablet forms and commonly researched for weight management. It has early human trial data behind it, but it is still investigational and is not FDA-approved; research-grade VK2735 sold for laboratory use is not the trial drug.