Liraglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist, developed by Novo Nordisk under the code NN2211. It is the molecule sold as Victoza for type 2 diabetes and, at a higher dose, as Saxenda for chronic weight management. The FDA approved Victoza in 2010 and Saxenda in 2014, with a later approval for obesity in adolescents aged 12 and up in 2020, per the StatPearls monograph. It is given as a daily subcutaneous injection. This is an approved prescription medicine, not a research-only compound, and nothing here is medical or dosing advice.
What it is
Liraglutide is an engineered version of human GLP-1, the gut hormone released after eating. It shares about 97% of its amino acid sequence with native GLP-1(7-37). Two changes make it a drug rather than a hormone that disappears in minutes: one amino acid swap (Lys34 to Arg) and the addition of a 16-carbon fatty acid chain, linked through a glutamate spacer at Lys26. That fatty acid is what matters. It lets the molecule bind reversibly to albumin in the blood and self-associate at the injection site, which slows absorption and shields it from the DPP-4 enzyme that normally chews up GLP-1. The result is a half-life of roughly 13 hours instead of the 1 to 2 minutes of the natural hormone. The design history is laid out by the originating scientists in ACS Pharmacology & Translational Science.
How it works
Liraglutide activates the GLP-1 receptor, which produces several effects relevant to blood sugar and weight:
- Glucose-dependent insulin release. It prompts the pancreas to secrete insulin mainly when blood glucose is high, which limits hypoglycemia risk.
- Glucagon suppression, reducing the liver's glucose output.
- Slowed gastric emptying, so food leaves the stomach more gradually.
- Reduced appetite, acting on appetite-regulating centers in the brain.
Those last two are why the same molecule, dosed higher, became a weight-management drug. Details are summarized in DrugBank.
What the research shows
Liraglutide has a deep clinical record. The standout cardiovascular study is LEADER, published in the New England Journal of Medicine in 2016. It randomized 9,340 people with type 2 diabetes at high cardiovascular risk to liraglutide or placebo and followed them for a median of 3.8 years. The primary composite outcome (cardiovascular death, nonfatal heart attack, or nonfatal stroke) occurred in 13.0% on liraglutide versus 14.9% on placebo, a hazard ratio of 0.87 (95% CI 0.78 to 0.97), with a parallel reduction in cardiovascular and all-cause death. The trial summary and figures are catalogued at PubMed. Beyond LEADER, the drug has been studied across diabetes, obesity, and adolescent populations.
It carries a boxed warning: liraglutide caused thyroid C-cell tumors, including medullary thyroid carcinoma, in rodents, and it is contraindicated in people with a personal or family history of medullary thyroid carcinoma or MEN2 syndrome.
Regulatory and sport status
Liraglutide is approved in the US, EU, and many other markets. As of December 2024 the FDA also approved a generic version of the injection. GLP-1 receptor agonists are not on the WADA Prohibited List, so liraglutide itself is not a banned substance in sport, though athletes should always check the current list.
The buyer's quality angle
Because liraglutide is a well-known, in-demand GLP-1, it also shows up in the gray market sold as a "research" peptide outside the regulated supply chain. The pharmaceutical product comes with the manufacturing controls and labeling that approval requires. Material sold for research carries none of that by default. If you are evaluating any peptide from that channel, the things that actually tell you something are a recent certificate of analysis (COA) from an independent lab, identity confirmation by mass spectrometry, and a purity figure by HPLC, ideally with named impurities rather than a single round number. peptideone aggregates third-party testing and vendor signals so those claims can be compared rather than taken on faith. None of that turns an unapproved product into something cleared for human use.