Peptides

The US FDA defines peptides as being 40 amino acids or less

The US Food and Drug Administration regulates these short strings of amino acids as drugs and approves them for commercial use. These products may be produced naturally or synthesized via medicinal chemistry for therapeutic use.

Diabetes drug GLP-1 is a peptide (that's what the 'P' is for)

Glucagon-like peptide-1, or GLP-1, is one of the most well-known peptides in common use. In 2024, 26.5% of all adults with diagnosed diabetes used the substance. GLP-1 was particularly popular among people with diabetes aged 50-64, followed by younger adults and then seniors aged 65+.

Peptides account for 31 of 370 new drugs approved by US FDA between 2016 and 2023

Among the approved peptide-based drugs is the first-ever treatment for Rett syndrome, a rare inherited neurologic disorder that leads to a progressive loss of motor skills and language. Peptides are particularly attractive for multiple reasons, including their ability to selectively bind to cellular receptors to either activate or inhibit their function.

See the first dog ever treated with insulin—a peptide

Frederick Banting and his graduate student Charles Best were the first to isolate the peptide insulin from dogs. They induced diabetes in the animals and then treated them with this peptide.

Peptide research dates back to the late 1800s

Peptide science dates back to the late 1800s with some early peptide synthesis work, but peptides took off in the medical sphere after surgeon Frederick Banting and his colleague's isolation of insulin from dog pancreases in 1921.

The word peptide comes from Greek

Originating from the Greek term "peptos," which means digestible, peptide as a word refers to two or more amino acids. (Some users may encounter a paywall.)

Leonard Thompson was the first human to receive an insulin injection for diabetes

In January 1922, the 14-year-old was the first person to receive an insulin injection to treat diabetes, just months after insulin was isolated in dogs and used to treat their induced diabetes. Thompson had an allergic response to an apparent impurity in the injection, but his second dose, 12 days later, was a success.

Early peptide research focused on isolating the substances from animal tissue

In the first half of the 20th century, peptides including insulin and adrenocorticotropic hormone were isolated from animals to provide life-saving medicines. ACTH was isolated from the pituitary glands of cows and pigs and insulin was isolated from the pancreas of dogs and cows.

The US FDA issued a 2025 warning about BPC-157 and other popular peptides

BPC-157, which mimics a naturally occurring gut peptide involved in soft tissue repair, has been marketed for various regenerative properties. But the FDA warned in July 2025 that it doesn't have enough data to assess its safety in humans and that such products may also pose risks related to contamination.

Two festival-goers were hospitalized after receiving peptide injections, raising questions

Investigative journalism shop ProPublica wrote about two people who became extremely ill following antiaging peptide injections. Authorities were examining whether the individuals were sickened by an infection, contamination related to the injections, or an issue with the medication itself, according to documents obtained by the journalists at ProPublica.