Phase 1 — Early human studies
Early studies evaluated safety, tolerability, pharmacokinetics and pharmacodynamic effects across different dose levels. These studies provided the foundation for later dose-ranging trials.
Research guides
These guides explain common research terms, evidence limitations, storage and analytical documentation. They are educational and do not provide medical or dosing advice.
What Is Retatrutide?
Retatrutide is an investigational peptide designed for simultaneous activity at GLP-1, GIP and glucagon receptors.
What Is GHK-Cu?
GHK-Cu is a copper-binding peptide that has been examined in laboratory research involving signalling, extracellular matrix biology and formulation science.
What Is BPC-157?
BPC-157 is a synthetic peptide widely discussed in preclinical research. Human evidence and regulatory approval remain limited.
What Is TB-500?
TB-500 is a synthetic research peptide associated with thymosin-beta-4 fragments and is primarily discussed in preclinical research contexts.
What Is NAD+?
NAD+ is a naturally occurring coenzyme involved in redox reactions and many cellular processes.
What Are Research Peptides?
Research peptides are peptide materials supplied for controlled scientific, analytical or development work rather than approved therapeutic use.
Research Peptide Storage Guide
Storage requirements depend on the compound, formulation and supplier documentation. Temperature, light, moisture and repeated handling can affect stability.
How to Read a Certificate of Analysis (COA)
Learn how to check batch identity, analytical methods, HPLC purity, mass spectrometry results and laboratory report details.
Why Batch Testing Matters
Batch testing helps connect a specific sample or production lot with analytical information and traceability records.
Research Pen vs Lyophilised Vial
Compare pre-filled research pens and freeze-dried vials, including preparation, storage, handling, traceability and laboratory workflow.
Alluvi Retatrutide 40mg Stability Test
Review the reported 56-day room-temperature study timeline with independent Janoshik concentration, purity and pH results.
Research Peptide FAQ
Answers to common questions about research-use terminology, storage, laboratory reports, indexing and responsible website information.
Retatrutide Clinical Development — Phase 1 to Phase 3
Retatrutide (LY3437943) is an investigational GIP, GLP-1 and glucagon receptor agonist being developed by Eli Lilly. The clinical-development programme has progressed from early safety and dose-finding studies through large Phase 3 trials in obesity, type 2 diabetes and obesity-related complications.
Phase 2 — Obesity dose-ranging study
In the peer-reviewed Phase 2 obesity trial, mean body-weight change at 48 weeks was approximately −8.7% with 1 mg, −17.1% with 4 mg, −22.8% with 8 mg and −24.2% with 12 mg, compared with −2.1% with placebo. Gastrointestinal adverse events were the most commonly reported and were dose-related.
Phase 3 — TRIUMPH-1
In adults with obesity or overweight without diabetes, Lilly reported average weight reductions at 80 weeks of 19.0% with 4 mg, 25.9% with 9 mg and 28.3% with 12 mg. In a prespecified extension for participants with baseline BMI ≥35, the 12 mg group reached an average 30.3% reduction at 104 weeks.
Phase 3 — TRIUMPH-2
In adults with obesity or overweight and type 2 diabetes, Lilly reported average weight reductions at 80 weeks of 12.7% with 4 mg, 19.1% with 9 mg and 20.8% with 12 mg, alongside average A1C reductions of up to 1.6 percentage points.
Phase 3 — TRIUMPH-3
In adults with severe obesity and established cardiovascular disease, with or without type 2 diabetes, Lilly reported average weight reduction of up to 22.6% at 80 weeks. Cardiovascular event analyses were also reported, although these should not be interpreted as establishing cardiovascular benefit.
Phase 3 — TRIUMPH-4
In adults with obesity or overweight and knee osteoarthritis, Lilly reported average weight reduction of up to 28.7% at 68 weeks, together with substantial improvement in WOMAC knee-pain scores.
Phase 3 — TRANSCEND-T2D-1
In adults with type 2 diabetes inadequately controlled with diet and exercise, Lilly reported average A1C reductions of 1.7–2.0 percentage points at 40 weeks and average weight reduction of up to 16.8% at the 12 mg dose.
Ongoing Phase 3 programme
Additional Phase 3 studies continue to assess retatrutide across obesity, diabetes and related conditions, including alternative dose-escalation strategies. Study status and conclusions can change as trials complete and full results are published.
Regulatory status: Retatrutide remains investigational and is not currently
approved by the FDA, MHRA or another major medicines regulator. Clinical-trial findings relate
to Lilly's investigational medicine used under controlled study conditions and do not establish
that any third-party research material is equivalent to Lilly's clinical-trial product.