Retatrutide

Clinical maturity: Advanced Phase 3 investigational programme

Clinical trials use once-weekly subcutaneous injection. Material sold online as 'retatrutide' is unapproved, unstudied in humans as sold, and outside any regulated supply chain.

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.

A single peptide engineered to hit three metabolic receptors, adding glucagon-receptor agonism (which raises energy expenditure) to the incretin pair.

• The largest weight loss yet seen in an incretin-class trial programme
• Improvements in liver fat
• Better body composition outcomes

Published mid-stage human trials showed large average weight reduction, and the Phase 3 programme is advanced. Efficacy confidence for weight loss is high; long-term safety confidence is not, simply because the long-term data do not exist yet. Approved status and durable safety are different questions from 'does it work in a trial'.

• Randomised Phase 2 trials reporting substantial dose-dependent weight reduction.
• Advanced Phase 3 programme in obesity and related metabolic disease.

• Rodent models of triple agonism showing increased energy expenditure alongside reduced intake.

Animal and cell findings are Level 1–2 evidence.

• Incretin agonism reduces appetite and improves glycaemic handling.
• Glucagon receptor agonism increases energy expenditure and hepatic fat mobilisation — the piece that distinguishes it from dual agonists.

• Gastrointestinal effects consistent with the class, dose-related.
• Heart-rate increases and glucagon-related metabolic effects require monitoring in trials.
• Long-term safety is genuinely unknown; that is the honest answer.

Not approved in any region. In advanced Phase 3 development (the TRIUMPH programme) for obesity and related metabolic conditions. Anything sold to the public as 'retatrutide' today is outside approved medical supply.

• Baseline · Global

  Investigational only; advanced Phase 3 programme in obesity and metabolic disease.

• L4Strong humanPhase 2 dose-ranging obesity trial

  Randomised, placebo-controlled, dose-ranging — Adults with obesity

  Dose-dependent weight reduction of a magnitude not previously seen in the class.

• Completed Phase 3 readouts with full safety datasets.
• A regulatory approval decision in a major region.

• Trial registryClinicalTrials.gov — TRIUMPH-5: retatrutide in obesity with cardiovascular disease (NCT06662383)
• Trial registryClinicalTrials.gov — TRIUMPH-Outcomes: cardiovascular outcomes trial of retatrutide (NCT06383390)

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.

1. 2026-07-02

   Baseline entry: efficacy confidence for weight loss set high; safety confidence held low pending Phase 3 completion.

   L4Strong humanRating movedBaseline entry
   Randomised human trial data support large weight reduction. Long-term safety and a regulatory decision are still outstanding, so the two axes are rated separately.