What it is
Lanreotide is an eight-amino-acid peptide drug that copies somatostatin, the hormone the body uses to switch other hormones off. The label spells out its structure:
- Eight amino acids closed into a ring by a disulfide bond between two cysteines;
- A mirror-image D-2-naphthylalanine at the start — a bulky, non-natural amino acid — and a D-tryptophan at position 4;
- Threoninamide at the end, which caps the chain.
The free peptide weighs 1,096.34. Natural somatostatin is 14 amino acids long; a single lanreotide injection is designed to cover four weeks.
How it works
The Somatuline Depot label describes lanreotide binding strongly to somatostatin receptors 2 and 5 and more weakly to 1, 3 and 4, with receptors 2 and 5 responsible for lowering growth hormone. After a single injection, growth hormone falls quickly and stays down for at least 28 days.
Like the hormone it copies, it suppresses a long list of others: motilin, gastric inhibitory peptide and pancreatic polypeptide at baseline; gastrin and cholecystokinin after meals. It also delays and reduces insulin release after a meal, which the label reports as a transient, mild glucose intolerance in healthy volunteers, and it slows gallbladder emptying — the mechanism behind its gallstone warning.
A depot made of the drug itself
Lanreotide's monthly form carries no polymer or other slow-release carrier. The syringe holds a supersaturated solution — 24.6% lanreotide by weight in water, with acetic acid to set the pH and nothing else. The label says the formulation "is thought to form a drug depot at the injection site" on contact with body fluids, and that the drug most likely leaves it by passive diffusion.
The result, per the label:
| Measure | Figure |
|---|---|
| Half-life | 23 to 30 days |
| Absolute bioavailability (healthy volunteers, 60 / 90 / 120 mg) | 73.4% / 69.0% / 78.4% |
| Peak level | During the first day |
| Level above 1 ng/mL | Throughout 28 days at 90 and 120 mg |
What it is approved for
| Condition | Evidence on the label |
|---|---|
| Acromegaly | Two long-term randomised studies; the first began with a 4-week placebo-controlled phase in 108 patients |
| Gastroenteropancreatic neuroendocrine tumours (inoperable, well- or moderately-differentiated) | Study 3: 204 patients, 120 mg or placebo every 4 weeks for up to 96 weeks. Progression or death: 31.7% vs 58.3%; median progression-free survival not reached at 22 months vs 16.6 months; hazard ratio 0.47 |
| Carcinoid syndrome | Study 4: 115 patients, 16 weeks. Rescue octreotide used on 34% of days vs 49% on placebo (p = 0.02) |
The tumour result is what separates lanreotide's label from octreotide's: octreotide's label states that its trials did not show an effect on tumour size or growth, while lanreotide's carries a tumour-growth indication backed by a placebo-controlled trial. The trial enrolled only patients whose tumours produced no hormone symptoms, and 45% of them had pancreatic primaries.
Safety
The label's warnings follow from what a broad hormone suppressor does: gallstones and their complications (cholecystitis, cholangitis and pancreatitis have been reported after marketing), high or low blood sugar because insulin and glucagon are both suppressed, slow heart rate (sinus bradycardia in 5.5% of patients across three pooled cardiac studies in acromegaly), reduced thyroid function, and fatty stools that can point to reduced pancreatic enzyme output. The most common reactions in the acromegaly studies were diarrhoea, gallstones, abdominal pain, nausea and injection-site reactions.
Where it stands
Drugs@FDA lists four lanreotide applications on 2026-09-30:
| Application | Holder | Type | Approved |
|---|---|---|---|
| NDA 022074 — Somatuline Depot | Ipsen | New molecular entity | 2007-08-30 |
| NDA 215395 — lanreotide injection | InvaGen (Cipla) | New formulation or new manufacturer | 2021-12-17 |
| ANDA 217193 | InvaGen (Cipla) | Generic | 2024-05-21 |
| ANDA 218217 | Amneal | Generic | 2026-09-18 |
PubMed indexes 1,559 records for lanreotide, 92 tagged as randomised controlled trials (2026-09-30). The label specifies administration by a healthcare provider, as a deep injection in the upper outer buttock; how much and how often is set by the prescriber against growth-hormone and IGF-1 results.
Related reading
Lanreotide is one of two eight-amino-acid copies of somatostatin in this library; the other is octreotide, whose capsule form lists lanreotide-treated patients among those it may switch. The hormone it lowers is the one that growth-hormone releasers such as tesamorelin push up, and the IGF-1 it reduces is the natural counterpart of IGF-1 LR3.