How Long Have Peptides Been Around?
125 years. Peptides were first discovered in 1901, when Emil Fischer built the first peptide bond in a lab. Walk the timeline from that moment to today's GLP-1 revolution.
125 Years on One Timeline
Peptide science begins in 1901 with a single lab bond and runs straight through to today's $30B GLP-1 era. Click any milestone below to see what happened, who did it, and why it mattered.
Era 1 -- The Pioneers (1901-1953)
Three people. Three breakthroughs. Together they turned peptides from a curiosity into a science -- proving the building blocks of life could be built, injected, and read.
1901
Emil Fischer
Stitched two amino acids into glycylglycine and coined the word peptide from the Greek peptein (to digest). Proved life's building blocks could be assembled by human hands.
1922
Banting & Best
A 14-year-old dying of type 1 diabetes was injected with pancreatic extract in Toronto. He recovered. Insulin became the first peptide to save a human life.
1953
Frederick Sanger
Spent 12 years piecing insulin together like a jigsaw with no picture on the box. Showed proteins aren't random blobs -- they're precise machines.
Era 2 -- The Synthesis Revolution (1963-1982)
Knowing a peptide's recipe was one thing. Building it was another. Two breakthroughs -- one chemical, one biological -- turned peptides from rare lab samples into industrial drugs.
before 1963
peptide synthesis was brutal
Even a short peptide meant months of painstaking solution chemistry: add one amino acid, purify, add the next, purify again. Each intermediate had to be isolated by hand.
after 1963 (Merrifield)
solid-phase synthesis (SPPS)
Bruce Merrifield anchored the first amino acid to a tiny resin bead so it couldn't wash away. The chain grew one link at a time without ever isolating intermediates.
1977
Genentech reprograms E. coli
Spliced a human gene into bacteria and produced somatostatin. For the first time, a living cell was reprogrammed to manufacture a human peptide on demand.
1982
Humulin approved by FDA
Human insulin grown in bacterial vats instead of harvested from pig pancreases. We no longer needed to borrow molecules from animals -- we could tell bacteria what to build.
Era 3 -- The Discovery Era (1992-2005)
Once we could build peptides, the next question was where to find new ones. The most important answer came from somewhere nobody was looking.
John Eng, an endocrinologist at a Bronx VA hospital, had a hunch. Venomous animals rapidly disrupt their prey's metabolism -- so their venom might be packed with useful peptides. Gila monsters eat only three or four times a year, and their venom aggressively regulates blood sugar during those rare meals. Eng isolated exendin-4: it mimicked human GLP-1, the hormone that triggers insulin release. The catch? Your body's own GLP-1 breaks down in about two minutes. The lizard version lasted hours.
1992 → 2005
13 years from venom to pharmacy
In 2005, the FDA approved exenatide (brand name Byetta) -- the first GLP-1 receptor agonist, built directly from a desert reptile's venom. Nobody knew it yet, but this was the seed of a $30 billion revolution.
Era 4 -- The GLP-1 Revolution (2017-2024)
Novo Nordisk solved the half-life problem with a fatty-acid tail that hitches a ride on albumin in your blood. One injection, once a week. What followed wasn't a drug launch -- it was a cultural event.
2017
Ozempic
Mechanism: GLP-1 agonist
Weight loss: ~10-12%
Impact: proved once-weekly peptide dosing works at scale.
2021
Wegovy
Mechanism: GLP-1 agonist (higher dose)
Weight loss: ~15%
Impact: numbers previously only seen with bariatric surgery.
2022
Mounjaro
Mechanism: GLP-1 + GIP dual agonist
Weight loss: up to 22.5%
Impact: proved multi-receptor agonists outperform single targets.
The Four Eras at a Glance
Each era solved the problem the previous one created -- discovery → manufacture → biology → medicine at scale.
Era 1 · 1901-1953
Pioneers
Defined what a peptide is, proved one can save a life, mapped the first sequence.
Era 2 · 1963-1982
Synthesis Revolution
SPPS shortened synthesis from months to days; Humulin made bacteria the new factory.
Era 3 · 1992-2005
Discovery Era
Gila monster venom delivered exenatide -- the first GLP-1 receptor agonist drug.
Era 4 · 2017-2024
GLP-1 Revolution
Once-weekly peptides reshaped obesity medicine and built a $30B drug class.
What's Next? Three Races, Right Now
Three races are happening simultaneously, and each could change what peptide therapy looks like within the next few years.
Race 1
the end of needles
Oral semaglutide proved a peptide can survive stomach acid, barely. Orforglipron and danuglipron are small-molecule GLP-1 agonists built to be swallowed like aspirin. If they work, injections become optional.
Race 2
stacking receptors
Tirzepatide hits two receptors. Retatrutide hits three -- GLP-1, GIP, and glucagon -- and phase 2 trials showed 24% body weight loss. If phase 3 confirms, it would be the most effective weight-loss drug ever made.
Race 3
AI-designed peptides
Nuritas and Peptone are using machine learning to design peptides evolution never produced -- optimized for stability, potency, and targets no natural peptide has ever hit.
Common Questions About Peptide History
Short, sourced answers to the questions people ask most about when peptides were discovered, who discovered them, and how old the science really is.
When were peptides discovered?
Peptides were discovered in 1901, when Emil Fischer built the first peptide bond in a lab by joining two amino acids into glycylglycine and coined the word peptide. That makes peptide science about 125 years old as of 2026.
Who discovered peptides?
Emil Fischer is credited with discovering peptides in 1901. Frederick Sanger later sequenced insulin in 1953, and Bruce Merrifield invented solid-phase synthesis in 1963 -- work that won the 1984 Nobel Prize in Chemistry.
Are peptides natural or synthetic?
Both. Peptides occur naturally in every living organism -- insulin, oxytocin, and glucagon are natural peptides -- and they can also be made synthetically. Lab-made peptides are chemically identical to their natural counterparts; only the production method differs.
What was the first peptide drug?
Insulin. In 1922 it saved 14-year-old Leonard Thompson, who was dying of type 1 diabetes in Toronto. In 1982, Humulin became the first recombinant-DNA peptide drug, made by reprogramming bacteria to produce human insulin.
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- Parkes DG et al. "Discovery and development of exenatide." Expert Opin Drug Discov. 2013;8(2):219-44. PMID 23231438
- Jastreboff AM et al. "Tirzepatide Once Weekly for the Treatment of Obesity." N Engl J Med. 2022;387(4):327-340. PMID 35658024
- Jastreboff AM et al. "Triple-Hormone-Receptor Agonist Retatrutide for Obesity -- A Phase 2 Trial." N Engl J Med. 2023;389(6):514-526. PMID 37366315
- Quianzon CC, Cheikh I. "100 Years since the Discovery of Insulin." Diabetologia. 2024. PMID 38540146
- Kimmerlin T, Seebach D. "'100 years of peptide synthesis': ligation methods for peptide and protein synthesis." J Pept Res. 2005. PMID 15705167
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