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Peptide Evidence Registry

GLP-1s & incretins

Tirzepatide

A dual GIP and GLP-1 receptor agonist with strong Phase 3 weight and glycaemic data.

L5Repeated human trialsApproved medicine (jurisdiction-specific) · FDA (US)Approved
How settled this rating is:
high confidence in the current evidence rating
Routes studied:
Subcutaneous injection
Also known as:
Mounjaro, Zepbound, GIP/GLP-1 dual agonist
Last reviewed:
2026-09-08
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Evidence passport

Tirzepatide

A one-screen evidence identity for this compound. These fields describe research maturity, confidence and legal status. They are not a safety guarantee, efficacy percentage or recommendation.

Reviewed 2026-09-08
Evidence level
L5Repeated human trials
Confidence
High confidence in rating
Regulatory status
Approved medicine (jurisdiction-specific) · See jurisdiction details
Development status
Approved

Evidence strength

Human efficacy evidence92 of 100 evidence strength

Higher = more and better-quality human evidence. It does not mean the effect is bigger or that the compound works for you.

Human safety evidence80 of 100 evidence strength

Higher = more mature, better-documented human safety data. It does not mean the compound is safer than one with a lower number.

The 0-100 values rate the strength and maturity of evidence, not how effective or safe the compound is.

Evidence base
Includes human studies
Furthest established stage
Approved
Human research maturity
Approved, large completed Phase 3 programme
Source curation
Sources fully curated

Routes recorded

SC injection

Overview

Human efficacy evidence strength92 of 100 evidence strength

Higher = more and better-quality human evidence. It does not mean the effect is bigger or that the compound works for you.

Preclinical (animal / lab) evidence strength85 of 100 evidence strength

Higher = more animal, tissue or cell research. Preclinical results are a starting point, not proof of a human benefit.

Human safety evidence strength80 of 100 evidence strength

Higher = more mature, better-documented human safety data. It does not mean the compound is safer than one with a lower number.

How to read these scores

Every number here rates the evidence, not the compound. They are editorial 0-100 strength ratings, not percentages, and not a rating out of five stars.

  • Human efficacy evidence strength — Higher = more and better-quality human evidence. It does not mean the effect is bigger or that the compound works for you.
  • Preclinical evidence strength — Higher = more animal, tissue or cell research. Preclinical results are a starting point, not proof of a human benefit.
  • Human safety evidence strength — Higher = more mature, better-documented human safety data. It does not mean the compound is safer than one with a lower number. A score of 80 does not mean “80% safe”.
  • Evidence level (L0-L5) — the strongest type of study behind the compound, from anecdote (L0) to large replicated human trials (L5). It is a description of the study evidence, not a quality, safety or recommendation rating.
  • Confidence — how likely we think it is that this rating changes as new research lands. Low confidence means the picture is unsettled, not that the compound is bad.

None of these ratings is medical advice, a safety guarantee, or a recommendation to use anything. How we grade evidence.

How far human research has progressed: Approved, large completed Phase 3 programme

Routes & formulations

Studied / approved routes

SC injection

Approved products (Mounjaro, Zepbound) are once-weekly subcutaneous injections. No approved oral or other-route formulation exists.

Route availability is not evidence of efficacy, and evidence from one route does not transfer to another. The Registry never provides dosing or sourcing information.

Peptide lifecycle

  1. Discovery

  2. Preclinical

  3. Phase I

  4. Phase II

  5. Phase III

  6. Approved

Approved

What it is

A single molecule that activates two incretin receptors at once — GIP and GLP-1 — designed to improve metabolic outcomes beyond GLP-1 alone.

What people claim

  • Greater average weight loss than single-agonist GLP-1s
  • Strong glycaemic control
  • Improves obstructive sleep apnoea severity in people with obesity

What the evidence actually says

Randomised trials, including head-to-head comparisons in some settings, show large average weight reduction and strong glycaemic effects. Real differences between individuals are wide — trial averages are not personal forecasts.

Related evidence

Useful next reads based on this compound — not recommendations.

Human evidence

  • Large randomised Phase 3 trials in type 2 diabetes and obesity.
  • Comparative trials against a single GLP-1 agonist in defined populations.
  • Trials in obesity-related conditions such as sleep apnoea.

Preclinical evidence

  • Receptor pharmacology characterising biased signalling at GIP and GLP-1 receptors.
  • Rodent metabolic models of combined incretin agonism.

Animal and cell findings are Level 1–2 evidence.

Mechanism and pathways

  • GLP-1 receptor agonism: insulin secretion, appetite suppression, slowed gastric emptying.
  • GIP receptor agonism: additional effects on adipose tissue handling and possibly nausea tolerance.

Safety and unknowns

  • Very common: gastrointestinal effects, strongly dose-related.
  • Notable: gallbladder events, pancreatitis (uncommon), dehydration.
  • Same precautionary thyroid labelling class as other incretin agonists in some regions.
  • Separately from the molecule: FDA continues to warn about unapproved and compounded GLP-1 products, citing adverse-event reports, fraudulent or inaccurate labelling, shipping without proper temperature control, and dosing errors involving multi-dose vials and unfamiliar syringes. That is a product-quality and supply-chain risk, not a property of the approved medicine.

Cancer relevance

This section covers questions raised by how the compound works in the body, plus anything regulators and trial teams keep an eye on. It is not a statement that this compound causes cancer — for most compounds here, no human data exist in either direction.

Monitored in trials; not demonstrated in humans

Carries the same rodent-derived precautionary thyroid labelling as other incretin drugs in several regions. No demonstrated human cancer causation; long-term surveillance is ongoing.

Regulatory status

Regulatory decisions apply to specific jurisdictions, products, formulations and indications. An approval elsewhere is not automatically an approval in your country.

Named regulators: FDA (US)

Approved in multiple regions for type 2 diabetes (Mounjaro) and, under a separate brand (Zepbound), for chronic weight management. In December 2024 the FDA approved Zepbound as the first medication for obstructive sleep apnoea in adults with obesity. Additional indications vary by regulator. On 27 August 2026 the US Court of Appeals for the Fifth Circuit upheld FDA's determination that tirzepatide is no longer in shortage, rejecting a challenge brought by compounding interests. The practical effect is to reinforce the shortage delisting and the end of shortage-based routine copying of the approved product; it does not mean every form of individually tailored compounding is categorically unlawful, since narrow statutory exceptions can still apply. This is legal and regulatory evidence about US supply routes, not efficacy or safety evidence about the molecule.

  • 2024-12-20 · United States

    FDA approved Zepbound as the first medication for obstructive sleep apnoea in adults with obesity.

Key study types

  • L5Repeated human trialsPhase 3 obesity programme

    Randomised, double-blind, placebo-controlled — Adults with obesity

    Large average weight reduction; wide individual variation within trial arms.

Evidence grade

L5Repeated human trialsHigh confidence in rating

Substantial, consistent controlled human evidence supporting a specified outcome, preferably independently replicated. Approval is reported separately.

What would change our rating?

  • Long-term cardiovascular and mortality outcome data reaching maturity.
  • Robust comparative effectiveness data against triple agonists.

References and sources

Source transparency

A provenance snapshot of this profile. Counts show what kinds of sources are cited, not how much scientific weight each source deserves.

Sources fully curated
Last editorial review
2026-09-08
Recently reviewed · 38 days ago
Linked curated sources
3
Sources still pending
0
External specialist reviews
0
None recorded for this profile
Regulatory / label: 3

Review provenance

Registry editorial review: Colin Jackson-White, creator and editor, who is not a doctor or clinician. External specialist review is credited only when a named reviewer has completed a review of this exact profile.

Literature-discovery and AI tools may help locate or challenge candidate evidence, but they are not counted as evidence sources here. Registry judgements are tied to the underlying papers, trial records, regulator documents and official study records.

Source hierarchy: regulatory documents and trial registries first, peer-reviewed work next, sponsor material flagged as non-independent. We never use supplier or clinic marketing as evidence, and where a verified source has not yet been curated we say so rather than inventing one.

Evidence change history

These entries record changes to our assessment of the published evidence — not changes to the compound itself.

No recorded changes yet. Baseline position set on 2026-09-08.

Related claims we’ve checked — in full

Claim verdict

GLP-1s

Supported by evidenceL5Repeated human trials

“Tirzepatide improves obstructive sleep apnoea in people with obesity.”

This verdict applies to the exact claim above. It is not a verdict on the compound overall, a safety guarantee, or a recommendation to use it.

Registry verdict

Supported — in the randomised trial populations studied.

Why this verdict

  • Dedicated randomised trials reported reduced apnoea severity.
  • Effects are tied to the studied populations and treatment durations.
  • This is a good example of a claim moving from 'promising' to 'supported' because someone ran the trial.