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Peptides, hormones and pipeline drugs

Peptide

A peptide is a short chain of amino acids; under FDA rules, chains of 40 amino acids or fewer are peptides and longer ones are proteins.

Clinician review pending Updated Peptides, hormones and pipeline drugs
DefinitionA peptide is a short chain of amino acids; under FDA rules, chains of 40 amino acids or fewer are peptides and longer ones are proteins.

What it means

Amino acids are the building blocks of proteins. Link a few to a few dozen together and you have a peptide. Many hormones are peptides, including insulin's partners GLP-1, GIP, amylin and glucagon.

The FDA treats chains of 40 amino acids or fewer as peptides, usually regulated as drugs, and longer chains as proteins, regulated as biologics. Semaglutide and tirzepatide are peptides, so copies would be generics, not biosimilars.

Most peptides are digested in the gut, which is why peptide drugs are usually injected. Oral semaglutide needs an absorption enhancer, and orforglipron avoids the problem by not being a peptide.

The word "peptide" is also used online to sell unapproved products. Being a peptide says nothing about whether something is safe, effective or approved. Only an FDA approval and its label tell you that.

Why it matters

Knowing what a peptide is helps you separate approved peptide medicines from unapproved products using the same word.

Related terms

Research peptides ("not for human use")BiosimilarGeneric drug (generic GLP-1)OrforglipronWhat are peptides for weight loss

Sources

  1. FDA: Biosimilars basics for patients

Clinician review pending. Drafted from primary sources and waiting for sign-off by a licensed clinician (MD, DO or PharmD) before launch. Every number is checked against its source. Drug facts are re-checked quarterly, prices monthly and whenever a label changes. How we review · Report an error