Body journeys · 36 molecules
Follow a molecule through the body.
Pick a molecule and scroll. Each journey shows where it goes and what it does, step by step, from the injection site to the organs it acts on. Every step links to its source.
- ● Real structure: built from an experimental Protein Data Bank entry
- ● Related structure: the body's own hormone or a close relative, labelled as a stand-in
- ● Schematic: no structure exists, so the scene is illustrative
Built on real 3D structures
These journeys dock the actual drug into its receptor, using coordinates measured by cryo-EM or X-ray crystallography.
Real structure · PDB 7KI0Approved GLP-1 medicine
Semaglutide
Semaglutide copies a gut hormone called GLP-1. It helps the pancreas release insulin when blood sugar is high, slows the stomach a little, and quiets hunger signals in the brain. A fatty side chain lets it stick to a blood protein, so it lasts about a week in the body. It is approved medicine.
- Bloodstream
- Pancreas
- Stomach
- Brain
- Fat tissue
- Heart
- Kidneys
- Liver
Approved. Approved by a major regulator after large trials. 
Real structure · PDB 7FIMApproved GLP-1 medicine
Tirzepatide
Tirzepatide is a small protein-like drug (a peptide, 39 building blocks long) that copies two gut hormones, GIP and GLP-1. Together they help the body control blood sugar and appetite. A fatty side chain lets it hitch a ride on a blood protein, so half of it is still there after about five days, and it is given once a week. It is approved for type 2 diabetes and weight management, and in the US for sleep apnea.
- Skin
- Bloodstream
- Pancreas
- Stomach
- Brain
- Liver
- Fat tissue
- Heart
Approved. Approved by a major regulator after large trials. 
Real structure · PDB 8YW3In clinical trials
Retatrutide
Retatrutide is an experimental once-a-week injection from Eli Lilly. It copies three natural gut and body hormones at once (GIP, GLP-1 and glucagon). In large trials, people lost a lot of weight, but it is not approved anywhere yet. Lilly says it plans to ask the US FDA for approval in early 2027.
- Bloodstream
- Brain
- Stomach
- Pancreas
- Fat tissue
- Liver
- Kidneys
- Heart
Phase 3. Large trials comparing it with placebo or other drugs. 
Real structure · PDB 6XOXOral GLP-1
Orforglipron
Orforglipron is a once-a-day tablet that copies a gut hormone called GLP-1. Most drugs like it are peptides that must be injected. This one is a small, non-peptide molecule that survives being swallowed. It is approved in the US and UK for weight management. The UK has also approved it for type 2 diabetes.
- Gut
- Bloodstream
- Pancreas
- Brain
- Stomach
- Fat tissue
- Liver
Approved. Approved by a major regulator after large trials. 
Real structure · PDB 9BP3Amylin analogue
Cagrilintide (and CagriSema)
Cagrilintide is an experimental drug that copies amylin, a hormone your pancreas makes to help you feel full. It is built to stay in the body for a long time, so in studies it is given once a week. It is not approved anywhere yet. Its maker has asked the US FDA to approve it combined with semaglutide in one product, called CagriSema.
- Pancreas
- Bloodstream
- Brain
- Fat tissue
- Gut
Phase 3. Large trials comparing it with placebo or other drugs. 
Real structure · PDB 7LLLApproved GLP-1 medicine
Exenatide
Exenatide is a lab-made copy of a hormone first found in the saliva of the Gila monster, a large lizard. It acts on the same receptor as the gut hormone GLP-1: it helps the pancreas release insulin when blood sugar is high and slows the stomach. It was approved in the US in 2005 for type 2 diabetes.
- Skin
- Bloodstream
- Pancreas
- Liver
- Stomach
- Brain
- Kidneys
Approved. Approved by a major regulator after large trials.
Approved GLP-1 medicine
- Related structure · PDB 6X18
Approved GLP-1 medicine
Dulaglutide
- Bloodstream
- Pancreas
- Stomach
- Heart
- Elsewhere
Approved. Approved by a major regulator after large trials. - Schematic animation
Approved GLP-1 medicine
Ecnoglutide
- Skin
- Bloodstream
- Pancreas
- Brain
- Gut
- Fat tissue
- Liver
Approved. Approved by a major regulator after large trials. - Related structure · PDB 6X18
Approved GLP-1 medicine
Liraglutide
- Bloodstream
- Pancreas
- Brain
- Stomach
- Fat tissue
- Heart
Approved. Approved by a major regulator after large trials. - Schematic animation
Approved GLP-1 medicine
Mazdutide
- Skin
- Bloodstream
- Pancreas
- Brain
- Liver
- Fat tissue
- Heart
Approved. Approved by a major regulator after large trials.
Amylin analogue
- Schematic animation
Amylin analogue
Amycretin
- Bloodstream
- Brain
- Stomach
- Pancreas
- Liver
Phase 2. Mid-size trials testing if it works. - Schematic animation
Amylin analogue
Eloralintide
- Bloodstream
- Brain
- Stomach
- Fat tissue
- Heart
Phase 3. Large trials comparing it with placebo or other drugs. - Schematic animation
Amylin analogue
Pramlintide
- Skin
- Bloodstream
- Stomach
- Pancreas
- Brain
Approved. Approved by a major regulator after large trials.
In clinical trials
- Schematic animation
In clinical trials
Maridebart cafraglutide (MariTide)
- Skin
- Bloodstream
- Elsewhere
- Brain
- Pancreas
- Stomach
- Fat tissue
Phase 2. Mid-size trials testing if it works. - Schematic animation
In clinical trials
Survodutide
- Skin
- Bloodstream
- Brain
- Stomach
- Liver
- Fat tissue
- Heart
Phase 3. Large trials comparing it with placebo or other drugs.
Approved peptide medicine
- Schematic animation
Approved peptide medicine
Bremelanotide (PT-141)
- Skin
- Bloodstream
- Brain
- Heart
- Stomach
- Kidneys
Approved. Approved by a major regulator after large trials. - Schematic animation
Approved peptide medicine
Elamipretide (SS-31)
- Skin
- Bloodstream
- Elsewhere
- Muscle
- Heart
Approved. Approved by a major regulator after large trials. - Schematic animation
Approved peptide medicine
Setmelanotide
- Skin
- Bloodstream
- Brain
- Fat tissue
- Elsewhere
Approved. Approved by a major regulator after large trials. - Related structure · PDB 7CZ5
Approved peptide medicine
Tesamorelin
- Skin
- Bloodstream
- Brain
- Liver
- Fat tissue
Approved. Approved by a major regulator after large trials.
Trending peptide
- Schematic animation
Trending peptide
AOD-9604
- Gut
- Bloodstream
- Elsewhere
- Fat tissue
- Pancreas
Phase 2. Mid-size trials testing if it works. - Schematic animation
Trending peptide
BPC-157
- Gut
- Bloodstream
- Heart
- Muscle
- Liver
- Elsewhere
Animals. Tested in animals, not properly in people. - Schematic animation
Trending peptide
CJC-1295
- Bloodstream
- Brain
- Liver
- Bone
- Heart
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
DSIP (delta sleep-inducing peptide)
- Gut
- Bloodstream
- Brain
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
Epitalon
- Brain
- Bloodstream
- Elsewhere
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
GHK-Cu (copper peptide)
- Bloodstream
- Skin
- Immune system
- Elsewhere
- Brain
Small human. Small or uncontrolled studies in people. - Related structure · PDB 7F9Z
Trending peptide
Ipamorelin
- Brain
- Bloodstream
- Liver
- Bone
- Gut
Phase 2. Mid-size trials testing if it works. - Schematic animation
Trending peptide
Kisspeptin
- Brain
- Bloodstream
- Elsewhere
Phase 2. Mid-size trials testing if it works. - Schematic animation
Trending peptide
KPV
- Brain
- Gut
- Immune system
- Skin
Animals. Tested in animals, not properly in people. - Schematic animation
Trending peptide
LL-37
- Immune system
- Skin
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
Melanotan II
- Bloodstream
- Skin
- Brain
- Gut
- Kidneys
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
MOTS-c
- Elsewhere
- Bloodstream
- Muscle
- Fat tissue
- Pancreas
- Bone
Animals. Tested in animals, not properly in people. - Schematic animation
Trending peptide
Selank
- Elsewhere
- Bloodstream
- Brain
- Immune system
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
Semax
- Elsewhere
- Bloodstream
- Brain
Small human. Small or uncontrolled studies in people. - Related structure · PDB 7CZ5
Trending peptide
Sermorelin
- Skin
- Bloodstream
- Brain
- Liver
- Bone
Small human. Small or uncontrolled studies in people. - Schematic animation
Trending peptide
TB-500 (thymosin beta-4 fragment)
- Skin
- Bloodstream
- Elsewhere
- Heart
- Immune system
Animals. Tested in animals, not properly in people.
Other
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