Compound family

Gut and intestinal peptides

In one sentenceThree peptides that act on the intestine rather than through the bloodstream: one that makes a shortened bowel absorb more, one swallowed as a capsule and never absorbed, and one whose phase 3 was stopped for futility.
Compounds3
Best gradeA Teduglutide
Approved medicines2 of 3
Prohibited in sport1 of 3

What this family is

This family is defined by where the drug works, not by what it is chemically. Teduglutide is a 33-residue GLP-2 analogue injected daily, and the only approved treatment that reduces dependence on intravenous feeding in short bowel syndrome. Linaclotide is a disulfide-locked 14-residue peptide taken as a capsule, approved for irritable bowel syndrome with constipation and chronic constipation, which the label describes as minimally absorbed with negligible systemic availability — it works on the surface it is already touching. Larazotide is an eight-residue tight-junction regulator for coeliac disease that got as far as phase 3 and no further.

The evidence separates them cleanly. Teduglutide's pivotal trial moved a hard, patient-relevant endpoint: 63% of patients reduced their weekly parenteral volume against 30% on placebo, and more than half gained at least one night a week off the drip. Linaclotide's 26-week phase 3 gave a third of patients a composite response against a seventh on placebo, a number needed to treat of about five. Larazotide's phase 2b met its endpoint at the lowest of three doses while the higher doses did nothing, and the confirmatory phase 3 was discontinued in 2022 after an interim analysis found the effect too small to chase. Two As and a C, and the C is the instructive one.

Each drug's main adverse effect is its own mechanism at a higher intensity: teduglutide is trophic to intestinal mucosa, so its label requires colonoscopic surveillance; linaclotide drives chloride secretion, so about one in twenty patients stops it because of diarrhoea. Teduglutide and linaclotide are prescription-only in every region LYO covers; larazotide is not approved anywhere and anything sold under the name is not the trial drug.

Grade counts across the family: 2 × A · 0 × B · 1 × C · 0 × D. The best grade here, A, means established in humans. How LYO grades →

The compounds, graded

Every member with its best-supported outcome grade, human-trial count and regulatory status. Each opens the full evidence page.

Teduglutide

A

A GLP-2 analogue and the only approved drug that reduces the need for intravenous feeding in short bowel syndrome.

Human trialsSTEPS phase 3 (n=86) and its extensions
StatusApproved (Rx)

Linaclotide

A

A 14-residue peptide taken by mouth that is not absorbed: it works entirely on the inside surface of the gut.

Human trialsPhase 3 programme (n=804 in the trial quoted here)
StatusApproved (Rx)

Larazotide

C

An eight-residue tight-junction regulator for coeliac disease: a phase 2b that met its endpoint at the lowest dose only, and a phase 3 stopped for futility.

Human trialsPhase 2b (n=342) positive at one dose; phase 3 (CeDLara) discontinued at interim analysis
StatusInvestigational (phase 3 discontinued)

Questions

Why group these three together?
Because they share a site of action rather than a receptor. All three act on or in the intestinal wall, and two of them barely enter the bloodstream at all — which is what makes an oral peptide drug possible.
Which of these can be taken by mouth?
Linaclotide. Its three disulfide bonds hold it together through the stomach and its target sits on the luminal surface, so it never needs to be absorbed. Larazotide was also oral; teduglutide is injected daily.
Is there a drug for coeliac disease?
No. Larazotide came closest — a positive phase 2b at one dose — and its phase 3 was stopped in 2022 for futility. A gluten-free diet remains the only treatment.

Written and maintained by LYO Research — how pages are written and checked. Reviewed 29 October 2026. Grades count human evidence only. Not medical advice. Correct this page →