Knowledge Base
Evidence-based reference articles covering every aspect of retatrutide — from its novel triple-agonist mechanism to clinical trial outcomes, safety data, and development milestones. Each article is sourced from peer-reviewed research and regularly updated as new data emerges.
Essential Reading
Retatrutide (Reta) Week by Week: Results Timeline, Week 1 to 80
How long does reta take to work? What the trials show from the first weeks of dose escalation to 24, 48 and 80 weeks, with a week-by-week results table.
How Long Has Retatrutide Been Around? History Since 2016
Retatrutide began as a Lilly lab compound around 2016, was first given to people in 2019, had Phase 2 results in 2023 and six Phase 3 readouts in 2025-26.
Weight Loss Outcomes with Retatrutide: Clinical Trial Results and Analysis
How much weight people lost on retatrutide in each trial, by dose and over time, how many reached 20% or more, and how it compares with other drugs.
Safety Profile of Retatrutide: Comprehensive Overview from Clinical Data
Retatrutide's safety record across Phase 1 to Phase 3: stomach side effects, dysesthesia, heart rate, lab changes and the open safety questions.
Mechanism of Action: How Retatrutide's Triple Receptor Agonism Works
Retatrutide activates three hormone receptors: GLP-1, GIP and glucagon. What each one does for appetite, blood sugar, energy use and liver fat.
All Articles
Is Retatrutide Safe? What Clinical Data Shows
Retatrutide safety data from Phase 2 and Phase 3 trials: adverse events, dysesthesia, discontinuation rates, and what remains unknown.
Peptide Quality Verification: COAs, Purity, and Red Flags
How to verify peptide quality using COA certificates, purity testing, and independent analysis. Learn what separates verified products from the rest.
Research Peptides vs Pharmaceutical Grade
The real difference between research peptides and pharmaceutical-grade products: GMP manufacturing, quality controls, and what it means for safety.
Retatrutide and Heart Health: Cardiovascular Data
Retatrutide cardiovascular data: blood pressure, cholesterol, triglycerides, and lipid improvements from clinical trials. No outcomes data yet.
Retatrutide and Kidney Disease: CKD Research
Retatrutide kidney data: UACR reduction, eGFR changes, and the TRANSCEND-CKD trial design. Early evidence in chronic kidney disease.
Retatrutide and Osteoarthritis: TRIUMPH-4 Results
TRIUMPH-4 Phase 3 data: retatrutide achieved 28.7% weight loss and 75.8% knee pain reduction in adults with obesity and osteoarthritis.
Retatrutide, PCOS, and Fertility: Women's Health
Retatrutide and PCOS, fertility, pregnancy, and birth control: what GLP-1 class data suggest and why no retatrutide-specific evidence exists.
Retatrutide for Type 2 Diabetes: TRANSCEND Trial Data
Retatrutide in type 2 diabetes: TRANSCEND-T2D-1 (A1C down 1.94 points, weight down 15.3% at 40 weeks) and the head-to-head TRANSCEND-T2D-2 vs Ozempic.
Retatrutide and Alcohol: What the Evidence Shows
Review of evidence on retatrutide and alcohol interactions, GLP-1 effects on drinking behavior, and safety concerns for combining alcohol with GLP-1 agonists.
Retatrutide and Bodybuilding: Body Composition Data
Evidence-based review of retatrutide body composition data including fat loss, lean mass, and relevance to bodybuilding. DXA scan results from Phase 2.
Retatrutide Injection Guide: How It's Administered
How retatrutide is administered in clinical trials: injection sites, technique, pen device, needle gauge, storage, and dose escalation protocol.
How to Get Retatrutide: Clinical Trials, Access, and Availability
Retatrutide is not approved. The two legitimate routes are clinical trials and Lilly's narrow expanded access program. Filing is planned by Q1 2027.
Retatrutide Cost and Pricing: What to Expect When It's Approved
No price set for retatrutide (not yet FDA-approved). Based on tirzepatide pricing, analyst projections, and the biologic lawsuit, here's what it may cost.
Is Retatrutide FDA Approved? Status and Release Date (2026)
No. Retatrutide is not approved anywhere. Six Phase 3 trials have reported and Lilly plans to file by Q1 2027, so the earliest decision is late 2027.
Retatrutide Side Effects: Complete Guide to Clinical Trial Safety Data
Retatrutide side effects from Phase 2 and Phase 3 trials: stomach effects by dose, how many stopped, the dysesthesia signal, and GLP-1 comparisons.
Retatrutide Receptor Activity: GLP-1, GIP, and Glucagon Pathways
How retatrutide acts at GLP-1, GIP and glucagon receptors: its relative strength at each, and how that balance differs from tirzepatide.
Retatrutide Half-Life and Dosing: Pharmacokinetic Profile Explained
Retatrutide's half-life is about 6 days, which is why it is injected once a week. How it is absorbed, when levels settle, and how it compares.
Retatrutide Development Timeline: From Discovery to Phase 3
Timeline of retatrutide from discovery through Phase 3, including TRIUMPH-4 results (-28.7% weight loss), dose escalation, and the 2026 readouts.
Liver Fat Reduction with Retatrutide: MASLD/NAFLD Implications
How much retatrutide lowered liver fat in trials, why glucagon drives the effect, and what it could mean for fatty liver disease (MASLD and MASH).
Metabolic Effects of Retatrutide: Glycemic, Lipid, Hepatic, and Cardiovascular Outcomes
Retatrutide's effects beyond weight loss: blood sugar, cholesterol and triglycerides, blood pressure, liver fat and inflammation markers in trials.
What Is Retatrutide? A Comprehensive Overview of LY3437943
Retatrutide (LY3437943) is Lilly's investigational weekly injection that acts on GLP-1, GIP and glucagon receptors. What it does and where it stands.
Pharmacokinetics of Retatrutide: Absorption, Distribution, Metabolism, and Excretion
How retatrutide is absorbed, carried and cleared: about 6-day half-life, albumin binding through a fatty-acid chain, and why that allows weekly dosing.
Pharmacology of Retatrutide: Drug Class, Receptor Binding, and Signal Transduction
Retatrutide's drug class, how strongly it binds GLP-1, GIP and glucagon receptors, the signalling behind its effects, and key preclinical findings.