NZ Retatrutide Research
TRIUMPH-4 topline: 28.7% average weight loss at 68 weeks /// Triple agonist: GIP · GLP-1 · GCGR receptor activation /// New Zealand · Independent Research Resource /// TRIUMPH-4 reported · additional Phase 3 readouts expected in 2026 /// TRIUMPH-4 topline: 28.7% average weight loss at 68 weeks /// Triple agonist: GIP · GLP-1 · GCGR receptor activation /// New Zealand · Independent Research Resource /// TRIUMPH-4 reported · additional Phase 3 readouts expected in 2026 ///
New Zealand’s Retatrutide Research Hub

The Next
Generation
Triple Agonist

Retatrutide simultaneously activates three metabolic receptors — GIP, GLP-1, and glucagon. Independent, evidence-based research on what that means for metabolic health in Aotearoa.

28.7%
Mean Weight Loss
Receptor Targets
Ph.3
Trial Stage
Phase 3 Topline

TRIUMPH-4: 28.7% Mean Weight Loss at 68 Weeks

Breaking down Lilly’s first successful Phase 3 readout in obesity with knee osteoarthritis — the numbers, the caveats, and what it means.

8 min read
Mechanism

Triple Receptor Agonism: Why the GCGR Target Changes Everything

How glucagon receptor activation sets retatrutide apart from existing GLP-1 therapies.

6 min read
NZ Access

Research-Use Peptides in New Zealand: A Legal & Practical Overview

Regulatory landscape, compounding context, and what researchers need to know.

5 min read

Three Targets.
One Molecule.

Where semaglutide and tirzepatide act on one or two receptors, retatrutide (LY3437943) is a once-weekly injectable peptide that simultaneously activates the GIP, GLP-1, and glucagon receptors — the first of its kind to reach late-stage clinical development.

The additional glucagon receptor component drives significantly greater energy expenditure and fat oxidation compared to GLP-1 monotherapy, which researchers believe explains the substantially higher weight loss figures seen in trials.

Phase 2 · NEJM 2023
“Retatrutide resulted in substantial reductions in body weight across all doses tested — exceeding results observed with approved agents.”
  • GLPreceptor
    GLP-1 Receptor Agonism
    Reduces appetite and food intake. Slows gastric emptying. Shared mechanism with semaglutide and tirzepatide.
  • GIPreceptor
    GIP Receptor Agonism
    Enhances insulin secretion and potentially improves GLP-1 receptor sensitivity. Also active in tirzepatide.
  • GCGreceptor
    Glucagon Receptor Agonism
    The third target — increases energy expenditure, drives hepatic fat reduction, and appears responsible for retatrutide’s superior weight loss profile.

Latest Research
& Analysis

All Articles
vs
Comparison

Retatrutide vs Tirzepatide: The Triple vs Dual Agonist Question

Does the glucagon receptor target justify the trade-offs? A clinical comparison.

NZ
New Zealand

Retatrutide in NZ: Regulatory Status, Research Access & Practical Guide

What New Zealanders doing metabolic research need to understand about access and the current regulatory framework.

TRIUMPH-4 Key Data

The numbers
behind the latest TRIUMPH headline

28.7%
Mean body weight reduction at 68 weeks in the 12 mg retatrutide arm
Lilly TRIUMPH-4 topline · Dec 2025
445
Participants randomized in the Phase 3 TRIUMPH-4 trial
NCT05931367
68wk
Co-primary endpoint timepoint used in the first successful Phase 3 readout
TRIUMPH-4 protocol
Receptor targets: GIP · GLP-1 · Glucagon. First triple agonist in Phase 3
LY3437943 · Eli Lilly

This page now includes Lilly’s December 2025 TRIUMPH-4 topline Phase 3 results alongside earlier published Phase 2 research. TRIUMPH-4 has not yet been fully peer reviewed. This site presents research information only. Individual outcomes vary. Not medical advice.