Glossary

Half-life

In one lineHow long until half the drug is gone.

Definition

The time for the concentration of a compound in the blood to fall by half. Native GLP-1 lasts minutes; semaglutide, engineered to bind albumin, lasts about a week, which is what makes once-weekly dosing possible. Many research peptides have half-lives of minutes, so what a vial claims to do and what it can physically do are often different things.

Where it matters on LYO

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