TL;DR
The triple-agonist that outscored tirzepatide in Phase 2. Still not approved.
What is it? Eli Lilly's investigational once-weekly peptide (LY3437943). Hits GIP, GLP-1, and glucagon receptors at once. The only triple-agonist in late-stage trials.
What does it do? GLP-1 kills appetite. GIP fine-tunes adipose and dampens GLP-1 nausea. Glucagon burns liver fat and raises resting energy expenditure. Three levers, one injection.
Does the evidence hold up? Phase 2: 24.2% body weight loss at 48 weeks on 12 mg. Liver-fat MASLD substudy: up to 82% reduction at 24 weeks. TRIUMPH-4 Phase 3 topline (Oct 2025): 28.7% at 68 weeks in obesity plus knee OA.
Who uses it? Nobody legally yet. Available only through clinical trials and gray-market channels.
Bottom line? Biggest pharmacological weight-loss effect ever brought to Phase 3. Approval is the only question left.
What It Is
Retatrutide is an investigational 39-amino-acid peptide engineered by Eli Lilly that simultaneously activates three metabolic hormone receptors: the glucose-dependent insulinotropic polypeptide receptor (GIPR), the glucagon-like peptide-1 receptor (GLP-1R), and the glucagon receptor (GCGR). Because it is a triple agonist — and because all three receptors play central roles in appetite, glycemia, and energy expenditure — retatrutide is frequently called a "triple-G" or "GGG" agonist in the literature. Its clinical development code is LY3437943, and as of April 2026 it is in Phase 3 for obesity, type 2 diabetes, obstructive sleep apnea, and knee osteoarthritis.
Structurally, the molecule is built on a GIP peptide backbone carrying two α-aminoisobutyric acid (Aib) substitutions and one α-methyl-L-leucine, plus a C20 fatty diacid conjugate that enables albumin binding and extends plasma half-life to roughly six days. That half-life — the same general range as semaglutide — is what allows once-weekly subcutaneous dosing. The Aib2 substitution protects the molecule from degradation by dipeptidyl peptidase-4 (DPP-4), the enzyme that inactivates native GLP-1 within minutes.
What distinguishes retatrutide from semaglutide (single GLP-1 agonist) and tirzepatide (dual GIP/GLP-1 agonist) is the added glucagon receptor arm. Glucagon agonism at pharmacological doses increases hepatic glucose output — which sounds counter-therapeutic — but also increases resting energy expenditure, lipolysis, and hepatic fat oxidation. The design logic is that simultaneous GLP-1R activation suppresses the hyperglycemic effect of glucagon while the energy-expenditure benefit is retained. Whether this logic holds up in long-term safety data is one of the central open questions of the program.
Phase 2 data are what vaulted retatrutide into "most-watched" status among incretin therapeutics. In the 2023 Phase 2 obesity trial (Jastreboff et al., NEJM), the 12 mg arm achieved a mean 24.2% reduction in body weight at 48 weeks — numerically the largest effect size reported for any anti-obesity pharmacotherapy in that timeframe, exceeding the ~20.9% reported for tirzepatide in SURMOUNT-1 at 72 weeks and roughly double the ~14.9% of semaglutide in STEP-1 at 68 weeks. In October 2025, Eli Lilly announced topline positive results from TRIUMPH-4, the first Phase 3 readout, which showed up to 28.7% mean weight loss at 68 weeks in adults with obesity and knee osteoarthritis.
Mechanism of Action
Retatrutide's therapeutic profile is the integrated output of three distinct receptor arms. Each receptor signals through its own G-protein-coupled pathway, but the downstream metabolic effects converge on appetite, glycemic control, and energy expenditure.
- GLP-1R agonism (appetite + insulin) — Activation of the GLP-1 receptor in pancreatic β-cells triggers cAMP/PKA signaling, enhancing glucose-dependent insulin secretion. In the central nervous system — particularly the arcuate nucleus, area postrema, and solitary tract — GLP-1R activation suppresses appetite, delays gastric emptying, and drives early satiety. This is the mechanistic backbone shared with semaglutide and the GLP-1 arm of tirzepatide.
- GIPR agonism (incretin synergy + adipose handling) — GIP receptor activation enhances glucose-stimulated insulin secretion, suppresses glucagon during hyperglycemia, and appears to improve adipose tissue insulin sensitivity. GIP agonism in the CNS also contributes to appetite suppression through nuclei distinct from GLP-1R populations, and may reduce GLP-1-induced nausea through anti-emetic effects in the area postrema (Coskun et al., 2022).
- GCGR agonism (energy expenditure + hepatic fat) — Glucagon receptor activation at pharmacological doses increases resting energy expenditure through hepatic thermogenic pathways, mobilizes free fatty acids for oxidation, and accelerates hepatic fat clearance. This is the mechanistic explanation for retatrutide's unusually large effect on liver fat — up to 82% reduction at 24 weeks in MASLD patients (Sanyal et al., 2024).
- Balanced potency profile — In the discovery paper (Coskun et al., 2022), retatrutide showed higher potency at GIPR than at GLP-1R and GCGR, with the receptor balance tuned to maximize weight-loss effect while minimizing glucagon-driven hyperglycemia. The net effect is glycemic improvement despite adding a hyperglycemic hormone arm.
- Gastric emptying delay — Urva et al. (2023) demonstrated that retatrutide delays gastric emptying on first dose with tachyphylaxis over repeated dosing — mechanistically similar to other GLP-1 agonists but of interest because the early satiety effect partly underlies the caloric deficit.
- CNS appetite integration — Chronic GLP-1R/GIPR activation reshapes hypothalamic and hindbrain circuits governing hunger and reward. Preclinical work shows reduced dopaminergic reward response to palatable food, reduced preference for high-fat diets, and altered anticipatory feeding behavior — all compatible with the anorectic phenotype observed clinically.
- Lipolysis and free fatty acid flux — GCGR agonism promotes adipose tissue lipolysis, increasing free fatty acid availability for oxidation and contributing to the accelerated fat mass loss observed in body-composition substudies of the Phase 2 type 2 diabetes trial.
- Blood pressure and lipid modulation — In Phase 2, retatrutide reduced systolic blood pressure, non-HDL cholesterol, and triglycerides. Some of this is weight-loss-attributable; the GCGR arm may contribute additional lipid-specific effects through hepatic VLDL handling.
What the Research Shows
Retatrutide has one of the most clearly delineated preclinical-to-clinical development arcs in the incretin space. Evidence spans balanced in-vitro receptor pharmacology, rodent obesity and diabetes models, Phase 1 pharmacokinetics, multiple Phase 2 trials, and the first positive Phase 3 readout.
- Discovery and preclinical (Coskun et al., 2022) — In vitro, LY3437943 showed balanced GCGR and GLP-1R activity but greater GIPR activity. In diet-induced obese mice, once-weekly LY3437943 decreased body weight and improved glycemic control more than matched GLP-1R/GIPR dual agonism, with the incremental effect attributed to the GCGR-mediated increase in energy expenditure.
- Phase 1b T2D (Urva et al., Lancet 2022) — Multiple ascending dose trial in type 2 diabetes. The 12 mg dose produced approximately −8.96 kg placebo-adjusted least-squares mean weight change at 12 weeks, with glycemic improvement and pharmacokinetics supporting once-weekly dosing. Safety signals were dose-dependent GI events consistent with the class.
- Phase 2 obesity (Jastreboff et al., NEJM 2023) — 338 adults with BMI ≥30 (or 27–30 with a comorbidity), randomized 2:1 to retatrutide vs placebo across 1 mg, 4 mg, 8 mg, and 12 mg arms. At 48 weeks, least-squares mean body weight change: −8.7% (1 mg), −17.1% (4 mg), −22.8% (8 mg), −24.2% (12 mg), vs −2.1% placebo. 48-week ≥15% weight loss reached 83% in the 12 mg arm.
- Phase 2 T2D (Rosenstock et al., Lancet 2023) — 281 adults with type 2 diabetes randomized to retatrutide (various doses), dulaglutide 1.5 mg, or placebo. At 36 weeks, HbA1c reduction up to 2.02% and mean weight loss 16.9% in the 12 mg arm. Retatrutide outperformed dulaglutide on both endpoints.
- Phase 2 MASLD substudy (Sanyal et al., Nat Med 2024) — 98 participants from the obesity Phase 2 cohort with metabolic dysfunction-associated steatotic liver disease and ≥10% liver fat by MRI-PDFF. At 24 weeks, mean relative liver fat reduction: −42.9% (1 mg), −57.0% (4 mg), −81.4% (8 mg), −82.4% (12 mg) vs +0.3% placebo. Resolution of steatosis (liver fat <5%) reached 85% in the combined 8 mg and 12 mg arms.
- Body composition substudy (Lancet Diabetes & Endocrinol 2025) — Substudy of the Phase 2 T2D trial showed retatrutide-induced weight loss was predominantly fat mass, with preservation of skeletal muscle mass proportionally greater than would be predicted by diet-induced weight loss alone.
- TRIUMPH-4 Phase 3 (topline October 2025) — Adults with obesity and knee osteoarthritis. 12 mg arm: −28.7% body weight at 68 weeks; WOMAC pain score reduced meaningfully vs placebo; 9 mg arm: −26.4%. First positive Phase 3 readout for the program.
- TRIUMPH program breadth — Retatrutide is in Phase 3 for obesity without comorbidity (TRIUMPH-1/2/3), obesity + knee OA (TRIUMPH-4), obesity + OSA, obesity + cardiovascular risk, and multiple T2D readouts. Additional Phase 3 readouts are expected through 2026, with registration submission anticipated to follow.
Honest Evidence Framing
As of April 2026 retatrutide has one positive Phase 3 readout (TRIUMPH-4) and a deep Phase 2 dataset. It is not yet approved anywhere for any indication. Long-term cardiovascular outcome data comparable to SELECT for semaglutide are not yet available. The glucagon arm has never been pushed this hard at scale in humans; surveillance for hepatic, cardiovascular, and gallbladder events will matter more here than for prior incretin classes.
Human Data
Retatrutide has an unusually front-loaded human evidence base for a compound still in Phase 3 — over 1,000 human participants across Phase 1, Phase 2, and the early Phase 3 program, with the first major Phase 3 readout already positive.
- Phase 1 (NCT04143802) — Single and multiple ascending dose in healthy adults and T2D. Established pharmacokinetics, once-weekly dosing rationale, and initial safety.
- Phase 1b T2D (Urva et al., 2022; PMID 36354040) — 12-week multiple ascending dose; approximately −8.96 kg placebo-adjusted weight change at 12 mg; HbA1c reductions across doses.
- Phase 2 obesity (NCT04881760; Jastreboff 2023; PMID 37366315) — 338 adults; 48-week primary analysis; up to −24.2% body weight at 12 mg.
- Phase 2 T2D (NCT04867785; Rosenstock 2023; PMID 37385280) — 281 adults vs placebo and dulaglutide 1.5 mg; 36-week HbA1c and weight outcomes; retatrutide superior on both.
- Phase 2 MASLD substudy (Sanyal 2024; PMID 38858523) — 98 participants; 24-week MRI-PDFF; up to 82.4% mean relative reduction in liver fat.
- TRIUMPH-1 (NCT05929066) — Obesity without comorbidity; Phase 3 readout anticipated 2026.
- TRIUMPH-2 (NCT05929079) — Obesity + T2D; Phase 3; 2026 readout anticipated.
- TRIUMPH-3 (NCT05882045) — Obesity + cardiovascular disease; Phase 3 outcomes trial; longer-horizon readout.
- TRIUMPH-4 (NCT05931367) — Obesity + knee OA; first positive Phase 3 topline October 2025.
- Body composition substudy (PMID 40609566) — Predominantly fat-mass loss with preservation of skeletal muscle mass in T2D Phase 2 cohort.
- OSA Phase 3 — Obesity + obstructive sleep apnea; readout anticipated 2026.
The breadth and simultaneity of the TRIUMPH program is itself notable — Lilly is running parallel registrational trials across several obesity-adjacent indications rather than pursuing a narrow obesity-monotherapy label first. If the remaining readouts track TRIUMPH-4 and the Phase 2 data, retatrutide would represent the largest pharmacological effect on body weight ever brought to regulatory filing.
Dosing from the Literature
All doses below are derived directly from published Phase 2 and Phase 3 clinical trial protocols. Retatrutide is not yet approved by any regulator and the final labeled dose titration has not been issued. This is research documentation, not medical advice.
| Protocol | Starting Dose | Maintenance | Titration |
|---|
| Phase 2 obesity (low-dose arm) | 2 mg/wk SubQ | 4 mg/wk | 2 mg for 4 wks → 4 mg |
| Phase 2 obesity (mid-dose arm) | 2 mg/wk SubQ | 8 mg/wk | 2 → 4 → 6 → 8 mg over 12 wks |
| Phase 2 obesity (high-dose arm) | 2 mg/wk SubQ | 12 mg/wk | 2 → 4 → 8 → 12 mg over 16 wks |
| TRIUMPH-4 (Phase 3) | 2 mg/wk SubQ | 9 or 12 mg/wk | Escalation over ~16 wks |
| Phase 2 T2D | 0.5–2 mg/wk | Up to 12 mg/wk | Slower escalation than obesity |
| Cycle length | Continuous | — | Weight regain expected on discontinuation (class effect) |
Dosing Disclaimer
Retatrutide is investigational. There is no approved human dose in any jurisdiction. Gray-market "research use only" vials carry the same risks as any unregulated peptide — variable purity, variable concentration, no clinical oversight. Weight regain after discontinuation is class-expected for GLP-1 family drugs. Never escalate faster than the clinical titration schedule: GI tolerability is dose-dependent, and faster titration amplifies nausea, vomiting, and dehydration risk.
Reconstitution & Storage
Retatrutide is supplied as a lyophilized powder for research vials or as pre-filled autoinjector pens in clinical trials. For reconstituted research vials, the key variables are vial mass, water volume, and weekly dose.
| Vial Size | BAC Water | Concentration | 2 mg Dose | 8 mg Dose |
|---|
| 10 mg | 1 mL | 10 mg/mL | 20 units (0.20 mL) | 80 units (0.80 mL) |
| 20 mg | 2 mL | 10 mg/mL | 20 units (0.20 mL) | 80 units (0.80 mL) |
| 20 mg | 1 mL | 20 mg/mL | 10 units (0.10 mL) | 40 units (0.40 mL) |
- Reconstitution — Inject bacteriostatic water slowly down the vial wall at 45°. Swirl, never shake. Solution should be clear and colorless.
- Storage — Unreconstituted lyophilized powder: refrigerate at 2–8°C long-term; room temperature acceptable short-term. After reconstitution: refrigerate at 2–8°C, use within 28 days. Do not freeze reconstituted peptide.
- Injection sites — Abdomen (2 inches from navel), anterolateral thigh, or upper arm. Rotate weekly.
- Inspection — Discard if cloudy, discolored, or if particulates are present.
→ Use the Kalios Peptide Calculator for exact syringe units
Side Effects & Risks
Important
This is an investigational compound. Outside clinical trials, sourcing is gray-market. Below is what the Phase 2 and early Phase 3 readouts show — ask your provider about trial access if interested.
The safety profile in Phase 2 and TRIUMPH-4 is consistent with the broader GLP-1 class, with additional glucagon-driven signals specific to retatrutide's design.
- GI tolerability (dose-dependent) — In TRIUMPH-4 at the 9 mg and 12 mg doses respectively: nausea ~38–43% (vs ~11% placebo), diarrhea ~33–35% (vs ~13%), constipation ~22–25% (vs ~9%), vomiting ~20–21% (vs 0%). Most events were mild-to-moderate and concentrated during titration.
- Heart rate — Small dose-dependent increase in resting heart rate (~5–10 bpm) consistent with the GLP-1 class, typically stable after titration.
- Hepatic signals — Because the GCGR arm increases hepatic glucose output and alters hepatic lipid handling, transaminase monitoring is more important with retatrutide than with pure GLP-1 agonists. Trial data show net improvement in MASLD markers, but individual-level LFT monitoring during titration is prudent.
- Glycemic effects in non-diabetics — In the obesity cohort, small transient increases in fasting glucose were observed at higher doses during early titration, consistent with GCGR-driven hepatic glucose output. This resolved with continued dosing as GLP-1/GIP arms dominated.
- Gallbladder events — As with all GLP-1 class agents, cholelithiasis and cholecystitis signals warrant monitoring, particularly during rapid weight loss.
- Pancreatitis — Class-level concern for GLP-1 agonists. Trial data do not show elevated rates, but patients with a history of pancreatitis should avoid.
- MTC / thyroid C-cell (class boxed warning) — GLP-1 receptor agonists carry a boxed warning for medullary thyroid carcinoma based on rodent data. Retatrutide has the same theoretical concern; personal or family history of MTC or MEN2 is a class-wide contraindication.
- Pregnancy and lactation — Not studied; class recommendation is discontinuation ≥2 months before attempting conception.
- Purity and sourcing (gray market) — As an unapproved investigational compound, only "research use" powder is available outside trials. Independent third-party HPLC and mass-spec purity data are the floor for any gray-market sourcing. Underdosed or impure product is a common failure mode.
- Drug interactions — Delayed gastric emptying affects oral drug absorption, particularly narrow-therapeutic-index medications (thyroid replacement, anticoagulants, anti-epileptics). Insulin secretagogues and basal insulin require dose reduction to avoid hypoglycemia.
- WADA status — Not specifically named as a prohibited substance, but as a metabolic modulator it could be evaluated under broader WADA categories. Athletes should assume it is restricted until formally clarified by their federation.
Bloodwork & Monitoring
For an investigational compound with the GCGR arm, monitoring is more extensive than for a pure GLP-1 agonist.
- Baseline CMP — Particularly ALT/AST and fasting glucose. Repeat at 4, 12, 24, and 48 weeks.
- HbA1c — Every 3 months in patients with T2D or prediabetes.
- Fasting lipid panel — Baseline and at 24 and 48 weeks. Expect improvement but document.
- Thyroid — Baseline calcitonin if family history concerns; not routine screening otherwise.
- Amylase / lipase — Baseline; repeat if any new abdominal pain.
- Weight and body composition — Weekly weight, DEXA every 3–6 months if muscle preservation is a clinical priority.
- Hydration and electrolytes — During rapid weight loss or aggressive titration, BUN/creatinine and sodium deserve attention.
- Heart rate and blood pressure — Baseline and at each escalation; a persistent resting HR increase of ≥15 bpm warrants evaluation.
- Pregnancy planning — Document contraception counseling in women of reproductive potential.
Commonly Stacked With
Retatrutide is an investigational monotherapy; combinations below describe community/practitioner patterns rather than trial-supported regimens.
Used by some clinicians to preserve lean mass and support fat oxidation during the aggressive fat-mass loss phase. The GHRH pathway is independent of incretin signaling. Evidence for combination safety is practitioner-level, not trial-level.
Growth hormone secretagogue stack added by some users to support muscle retention during rapid weight loss. Avoid in anyone with a history of cancer or active proliferative disease.
GI and mucosal protection during high-dose incretin therapy. Users experiencing significant GI side effects during titration sometimes add BPC-157 for gastric cytoprotection; the combination is mechanistically logical but not clinically tested.
Protein, creatine, resistance training
Not peptides, but the highest-leverage adjuncts: 1.6–2.2 g/kg/day protein, creatine 3–5 g/day, and 2–4 sessions/week of progressive strength training protect lean mass during rapid caloric deficit.
→ Check compound compatibility in the Stack Builder
Regulatory Status
Current Status — April 2026
Retatrutide is an investigational compound in Phase 3 clinical trials. It is not approved by the FDA, EMA, or any other regulatory authority for any indication. It is an active clinical asset of Eli Lilly and is not available by prescription.
As of April 2026, the TRIUMPH-4 Phase 3 readout (obesity + knee OA) has delivered positive topline data. The remaining obesity and T2D Phase 3 readouts are anticipated through 2026, with a regulatory submission expected to follow. If approved on the current trajectory, retatrutide would be among the first triple-agonist incretin therapeutics to reach market.
Retatrutide is not currently a WADA-banned substance as a specific named agent; however, as a peptide hormone with metabolic effects, use in competitive athletes is subject to S2 (peptide hormones, growth factors, related substances) and S4 (hormone and metabolic modulators) interpretations. Athletes subject to anti-doping testing should assume it is prohibited.
The FDA has not placed retatrutide on the Category 2 bulk drug list as of April 2026. Gray-market sourcing remains the only route of access outside clinical trials. This is, by current statute, unlicensed drug use.
Cost & Access
Retatrutide (LY3437943) is not approved for human use. It is an investigational Phase 3 triple GLP-1/GIP/glucagon receptor agonist under active development by Eli Lilly. As of April 2026, retatrutide remains investigational; the TRIUMPH-1 (obesity), TRIUMPH-2 (obesity with comorbidities), TRIUMPH-3 (cardiovascular outcomes), and TRIUMPH-4 trials have generated published Phase 2 data showing approximately 24% mean weight loss at 48 weeks at the 12 mg dose — substantially greater than tirzepatide's Phase 3 results. FDA approval is anticipated based on the trial readout schedule but has not been granted.
U.S. compounding pharmacies cannot legally compound retatrutide under current FDA bulk-substance rules because it is an actively developed sponsor drug without an approved reference product. Retatrutide is available only through research-chemical channels at variable quality and pricing. Independent third-party Certificate of Analysis (HPLC purity + mass spec) is the practical floor for due diligence.
Retatrutide is not on the Category 2 bulk substance list addressed by HHS Secretary Robert F. Kennedy Jr.'s February 2026 reclassification announcement, which applies specifically to Category 2 peptide bulk substances historically restricted from compounding. Retatrutide is an investigational sponsor-developed drug with an active Phase 3 program; its regulatory pathway is the conventional NDA route through Eli Lilly.
Estimated pricing as of April 2026. Actual costs vary by provider, location, and prescription status. Kalios does not sell compounds.
Related Compounds
People researching retatrutide often also look at these:
Weekly GLP-1 receptor agonist (Ozempic / Wegovy). The standard-bearer for GLP-1 weight loss.
Dual GIP/GLP-1 receptor agonist (Mounjaro / Zepbound). Superior weight-loss and glycemic efficacy vs semaglutide.
Dual GLP-1 / glucagon receptor agonist. Boehringer Ingelheim's competitor to retatrutide.
Dual GLP-1 / glucagon receptor agonist developed by Innovent / Eli Lilly, principally for Asian markets.
Dual GLP-1 / glucagon receptor agonist with emphasis on MASH (liver fat) alongside weight loss.
Key References
- Jastreboff AM, Kaplan LM, Frías JP, Wu Q, Du Y, Gurbuz S, Coskun T, Haupt A, Milicevic Z, Hartman ML. Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526. PMID: 37366315. DOI: 10.1056/NEJMoa2301972.
- Rosenstock J, Frías JP, Jastreboff AM, et al. Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo and active-controlled, parallel-group, phase 2 trial conducted in the USA. Lancet. 2023;402(10401):529-544. PMID: 37385280.
- Sanyal AJ, Kaplan LM, Frias JP, et al. Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial. Nat Med. 2024;30(7):2037-2048. PMID: 38858523.
- Coskun T, Urva S, Roell WC, et al. LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist for glycemic control and weight loss: From discovery to clinical proof of concept. Cell Metab. 2022;34(9):1234-1247.e9. PMID: 35985340.
- Urva S, Coskun T, Loh MT, et al. LY3437943, a novel triple GIP, GLP-1, and glucagon receptor agonist in people with type 2 diabetes: a phase 1b, multicentre, double-blind, placebo-controlled, randomised, multiple-ascending dose trial. Lancet. 2022;400(10366):1869-1881. PMID: 36354040.
- Urva S, Quinlan T, Landry J, Martin J, Loghin C. The novel GIP, GLP-1 and glucagon receptor agonist retatrutide delays gastric emptying. Diabetes Obes Metab. 2023;25(9):2642-2647.
- Rosenstock J, et al. Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2, double-blind, parallel-group, placebo-controlled, randomised trial. Lancet Diabetes Endocrinol. 2025. PMID: 40609566.
- Doggrell SA. Is retatrutide (LY3437943), a GLP-1, GIP, and glucagon receptor agonist, a step forward in the treatment of diabetes and obesity? Expert Opin Investig Drugs. 2023. PMID: 37086147.
- Kjeldsen SAS, et al. Retatrutide for the treatment of obesity, obstructive sleep apnea and knee osteoarthritis: Rationale and design of the TRIUMPH registrational clinical trials. PMID: 41090431.
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). N Engl J Med. 2022;387(3):205-216. PMID: 35658024. (Comparator reference.)
- Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP-1). N Engl J Med. 2021;384(11):989-1002. PMID: 33567185. (Comparator reference.)
- Lincoff AM, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (SELECT). N Engl J Med. 2023;389(24):2221-2232. PMID: 37952131. (Comparator reference.)
- ClinicalTrials.gov. A Study of Retatrutide (LY3437943) in Adult Participants Who Have Obesity or Are Overweight With Weight-Related Medical Problems (TRIUMPH-1). NCT05929066.
- ClinicalTrials.gov. A Study of Retatrutide (LY3437943) in Adult Participants With Obesity and Type 2 Diabetes (TRIUMPH-2). NCT05929079.
- ClinicalTrials.gov. A Study of Retatrutide (LY3437943) in Adult Participants With Obesity and Cardiovascular Disease (TRIUMPH-3). NCT05882045.
- ClinicalTrials.gov. A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight With Osteoarthritis of the Knee (TRIUMPH-4). NCT05931367.
- Eli Lilly and Company. Topline TRIUMPH-4 readout — retatrutide in adults with obesity and knee osteoarthritis. Press release, October 2025.
Last updated: April 2026 | Profile authored by Kalios Peptides research team