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Retatrutide

LY3437943 (Eli Lilly development code) · Triple G (nickname) · Reta (street name) · R-10, R-20 (product names listed in a Victorian health alert) · GLP-3, GLP-3 RT, GLP-3 Reta (vendor product names quoted in FDA warning letters) · 3G-RT, R-30 (vendor code names; our inference from vendor listings)

Retatrutide is an experimental weekly weight-loss injection from Eli Lilly. Large trials show major weight loss, but it is not approved anywhere, and vials sold online often fail tests123.

Last reviewed · First published · 63 sources · 33 min read · By the Pinc Peptide editors

Illustration: a glass vial with a pink label reading Retatrutide
Illustration, not a real product: an empty glass vial (photo: Missouri Historical Society, public domain) with our label. See every vial.

Quick answers

What is it?
An experimental weekly weight-loss injection from Eli Lilly1013. This lab-made peptide acts like three hormones at once: GIP, GLP-1 and glucagon10. It is not approved anywhere2. Companies still sell it labeled “for research purposes”5.
Does it work?
Yes, in large trials. In a 2026 trial, people without diabetes on the top dose lost 25% of their weight over 80 weeks, versus 3.9% on placebo47.
Is it safe?
Not fully known. Nausea and vomiting are common1. In one trial, about 1 in 5 on the top dose had odd skin feelings such as tingling, versus under 1% on placebo6. Effects beyond about two years are unknown14.
Is it legal?
Not approved anywhere, and US pharmacies may not make it25. Selling it for human use is illegal in the US and UK528. Lilly plans to seek FDA approval in the first quarter of 20274. Likely banned in sport32.
What is in the vials?
Often not as labeled. As of 30 September 2026, 63 of Finnrick’s latest 194 completed tests failed3. In 2026, only 1 of 18 Australian samples matched its label8. Officials there linked six liver injuries to such products, possibly from a contaminant9.

What it is

Retatrutide (development code LY3437943) is a synthetic peptide of 39 amino acids that activates three hormone receptors at once: the receptors for GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1), which tirzepatide also targets, plus the glucagon receptor101112. In obese mice, GIP and GLP-1 receptor activity cut calorie intake, and glucagon receptor activity added weight loss by raising energy expenditure10. The molecule carries a fatty-acid side chain, and its half-life in people is about 6 days, so it is injected under the skin once a week1213.

Eli Lilly discovered retatrutide and published its design and first human results in 20221013. Phase 2 results followed in 202314. The Phase 3 TRIUMPH program began in 2023, enrolled more than 5,800 people and reported its first results in December 20256. It is nicknamed “Triple G” for its three targets15.

Benefits: what the research shows

Unlike most peptides sold on the gray market, retatrutide has been tested in large, controlled human trials. In a Phase 2 trial of 338 adults with obesity, 12 mg weekly cut weight by 24.2% at 48 weeks versus 2.1% on placebo14. Five Phase 3 trials have reported. TRIUMPH-1 (2,339 adults without diabetes), published in September 2026, found average losses of 25.0% on 12 mg, 23.7% on 9 mg and 17.6% on 4 mg at 80 weeks versus 3.9% on placebo, counting people who stopped the drug47; by Lilly’s efficacy estimand, which assumes everyone stayed on treatment, the figures were 28.3%, 25.9%, 19.0% and 2.2%1. The TRIUMPH-1 paper also reported two groups within the trial, counting everyone randomized: among 243 people with obstructive sleep apnea, breathing pauses and shallow breaths per hour of sleep fell by 34.3 and 32.1 on 9 and 12 mg, versus 9.6 on placebo, and among 574 with knee osteoarthritis, pain scores fell 3.9 and 4.1 points, versus 2.547. TRIUMPH-4, in 445 adults with knee osteoarthritis59, found 23.7% loss on 12 mg versus 4.6% on placebo at 68 weeks, counting people who stopped the drug, and knee pain scores fell 3.7 points versus 2.1 (0 to 10 scale); by Lilly’s efficacy estimand, the figures were 28.7% versus 2.1% and 4.4 versus 2.4 points6. In type 2 diabetes, also counting people who stopped the drug, the peer-reviewed TRIUMPH-2 (1,152 adults) found 18.8% loss on 12 mg versus 5.1% on placebo at 80 weeks7, and TRANSCEND-T2D-1 (537 adults, 40 weeks) lowered HbA1c by 1.94 points on 12 mg versus 0.81 on placebo17. TRIUMPH-3 (1,949 adults with severe obesity and established heart or blood-vessel disease) found 22.6% loss on 12 mg versus 3.2% on placebo by Lilly’s efficacy estimand, the only weight figures in Lilly’s release, but heart events were rarer than expected in both groups and the result for them was inconclusive (MACE-3 hazard ratio 1.12, 95% CI 0.64 to 1.96)4. There are important limits. As of 8 October 2026, we found TRIUMPH-3 and TRIUMPH-4 reported only in Lilly press releases4663, and Lilly’s headline figures use the efficacy estimand, which gives larger numbers than the treatment-regimen estimand118. All the trials were funded by Lilly714. Safety data run to about two years1. The head-to-head trial against tirzepatide (TRIUMPH-5, about 800 adults) has not reported; its primary completion is estimated for November 202619. Outside trials, an analysis of 378 people using retatrutide from gray-market and other non-trial sources, not yet peer reviewed, reported average weight loss of 7.2% at 12 months versus 15.5% in trials at the same point20. The studies we found of its effects on cancer growth and on alcohol’s felt effects were all in mice or rats212260.

Key human studies

StudyDesignPeopleDose and routeResult
TRIUMPH-1, New England Journal of Medicine, 29 September 202647PubMed · DOI · NCT05929066 Phase 3 RCT, double-blind, placebo-controlled, 80 weeks, with a blinded 24-week extension (to 104 weeks) for 532 participants with BMI 35 or higher; adults with obesity or overweight and a weight-related condition, without diabetes 2,339 4, 9 or 12 mg subcutaneous once weekly, escalated from 2 mg every 4 weeks Weight change -17.6%, -23.7% and -25.0% vs -3.9% on placebo (treatment-regimen estimand)47; -19.0%, -25.9% and -28.3% vs -2.2% (efficacy estimand)1
Bellido V et al. (TRIUMPH-2), Lancet 20267PubMed · DOI · NCT05929079 Phase 3 RCT, double-blind, placebo-controlled, 80 weeks; adults with obesity or overweight and type 2 diabetes at 92 sites in 8 countries 1,152 4, 9 or 12 mg subcutaneous once weekly Weight change -11.9%, -16.8% and -18.8% vs -5.1% on placebo (treatment-regimen estimand); stopped treatment for adverse events or death 4%, 12% and 8% vs 5%7
TRIUMPH-4, Eli Lilly press release, 11 December 20256NCT05931367 Phase 3 RCT, double-blind, placebo-controlled, 68 weeks; adults with obesity or overweight and knee osteoarthritis, without diabetes 445 9 or 12 mg subcutaneous once weekly, escalated from 2 mg every 4 weeks Weight change -20.0% and -23.7% vs -4.6%, WOMAC knee pain -4.0 and -3.7 vs -2.1 points (treatment-regimen estimand); -26.4% and -28.7% vs -2.1%, and -4.5 and -4.4 vs -2.4 points (efficacy estimand); dysesthesia 8.8% and 20.9% vs 0.7%6
TRIUMPH-3, Eli Lilly press release, 23 July 20264NCT05882045 Phase 3 RCT, double-blind, placebo-controlled, 80 weeks; adults with BMI 35 or higher and established cardiovascular disease 1,949 9 or 12 mg subcutaneous once weekly, escalated from 2 mg every 4 weeks Weight change -21.6% and -22.6% vs -3.2% (efficacy estimand); MACE-5 hazard ratio 0.82 (95% CI 0.55 to 1.22), MACE-3 1.12 (0.64 to 1.96)4
Bajaj HS et al. (TRANSCEND-T2D-1), Lancet 202617PubMed · DOI · NCT06354660 Phase 3 RCT, double-blind, placebo-controlled, 40 weeks; adults with type 2 diabetes on diet and exercise alone, in the USA, Mexico and India 537 4, 9 or 12 mg subcutaneous once weekly HbA1c change -1.69, -1.86 and -1.94 points vs -0.81 on placebo; weight change -11.5%, -13.9% and -15.3% vs -2.6% (treatment-regimen estimand)17
Jastreboff AM et al., N Engl J Med 202314PubMed · DOI · NCT04881760 Phase 2 RCT, double-blind, placebo-controlled, 48 weeks; adults with obesity, or overweight with a weight-related condition 338 1, 4, 8 or 12 mg subcutaneous once weekly Weight change at 48 weeks -8.7% (1 mg), -17.1% (4 mg), -22.8% (8 mg) and -24.2% (12 mg) vs -2.1% on placebo; heart rate rose with dose, peaking at 24 weeks14

Doses studied

Doses below are what studies used or what a label says. They are not advice, and gray-market products may not contain what their label says.

In human studies

No dose is approved. Phase 3 trials started everyone at 2 mg once weekly and raised the dose every 4 weeks (2, 4, 6, 9, then 12 mg) to a target of 4, 9 or 12 mg once weekly, injected under the skin; the 4 mg arm used a single step at 2 mg16. Phase 2 tested 1 to 12 mg weekly for 48 weeks; starting at 2 mg rather than 4 mg reduced stomach side effects14. The Phase 1b trial used 0.5 to 12 mg weekly for 12 weeks13.

In animal studies

Mice: 30 nmol/kg by subcutaneous injection every other day, in an obesity and cancer model21. Rats: single subcutaneous doses of 0.03, 0.1 and 0.3 mg/kg given 3 hours before alcohol, in a study of alcohol’s felt effects22. These are research doses in animals, not human doses.

What users report

No community dosing page was cited for this compound.

Half-life
About 6 days13Phase 1b multiple-dose study in adults with type 2 diabetes (0.5 to 12 mg weekly for 12 weeks); supports once-weekly dosing
Routes
  • Subcutaneous injection once weekly (the only route in the human studies we found)
  • No human data found for any other route

Every dose studied for Retatrutide, with sources →

Quality and the gray market

What testing finds

Finnrick, a US testing service, had published 4,367 retatrutide tests covering 378 vendors (17 December 2024 to 25 September 2026). Of the latest 200, 131 passed, 63 failed and 6 were incomplete, a 32.5% fail rate among completed tests (as displayed on 30 September 2026)3. Its default pass mark is purity of at least 99.5% and content within 35% of the label36. In Australia, Leeder Analytical tested 18 retatrutide samples in 2026: only 1 matched its label, about 30% were over strength, about 30% were under, and 1 contained none8. A test arranged by University of Queensland researchers and PED Test Australia, a harm-reduction group, found 19 mg in a vial labeled 10 mg, at 16.6% purity, ABC News reported37. In a published letter, researchers from both groups reported three vials sold as retatrutide and labeled 10 mg that held 5.13 mg, 16.5 mg and 19.0 mg58. In a safety advisory reported by ABC News and republished by Pharmacy Today, the TGA said its laboratory had tested a product sold as retatrutide, in its original unmarked vial, and found no retatrutide but undeclared semaglutide, at about eight times the level in semaglutide products it had assessed3054. In New York, WIRED bought four vials of one brand at a bodega, one labeled retatrutide, and Finnrick found that none contained its labeled ingredient (15 September 2026)38.

How it is sold

Retatrutide is sold online mostly as “research use only” powder vials. FDA warning letters of 24 August 2026 quote product names such as “GLP-3 RT (Retatrutide) Research Peptide” and “GLP-3 Reta (Retatrutide)”3940, and Victoria’s alert lists products named Retatrutide, Reta, R-10 and R-209. The New York Post reported “ratatouille” as a TikTok code word (14 January 2026)41. It also reaches people through med spas, telehealth companies and pharmacies: Lilly’s six lawsuits of 12 August 2026 target compounding pharmacies, medical spas and online sellers, and Lilly says it has reported more than 14,000 websites, ads, posts and listings in over 100 countries2. Prices on Finnrick’s leaderboard for its eight top-rated retatrutide vendors ran from $0.60 to $6.40 per mg: six listed $0.60 to $1.23 and two listed $4.79 and $6.40 (tests through 25 September 2026; how prices were collected is not stated)3. Demand is high. Retatrutide made up 34.6% of the 21,253 test requests Finnrick received from May 2025 to May 2026 (our count from its chart data), more than any other product42. The r/Retatrutide forum had 160,567 weekly visitors on 30 September 2026, by our reading of its page43, and US Google searches for “retatrutide” peaked in the week of 7 June 202644.

Side effects and risks

  • Gut side effects are common and rise with dose: in TRIUMPH-1, nausea affected up to 42.4% and vomiting up to 25.3% of people on retatrutide, versus 14.8% and 4.8% on placebo1.
  • Dysesthesia (abnormal skin sensations such as tingling or pain) affected up to 20.9% on 12 mg in TRIUMPH-4 versus 0.7% on placebo; most cases were mild6.
  • Heart rate rose with dose in Phase 2, peaking at 24 weeks14, and low blood pressure was more common than on placebo in TRIUMPH-2 (up to 6% versus under 1%)7.
  • Stopping because of side effects reached 18.2% on 12 mg in TRIUMPH-4, and Lilly said these stops included some for perceived excessive weight loss6.
  • Effects beyond about two years, and on heart attacks, strokes and deaths, are unknown14.
  • Gray-market vials can be mislabeled, over- or under-strength, or a different drug entirely3830.
  • People with type 1 diabetes: a case report described near-ketoacidosis after an untested product sold online as retatrutide, during a gut infection and after skipped insulin45.
  • Legal and sport risk: selling it for human use is illegal in the US and UK, and athletes risk an S0 anti-doping violation (our reading of the WADA List)52832.

Documented harms

  • 19 Jun 2026Victoria’s Department of Health reported six cases of acute liver injury since January 2026 in people who used an unapproved product labeled retatrutide, possibly linked to a contaminant9.
  • 27 Jun 2026ABC News reported a vial labeled 10 mg that held 19 mg; a Melbourne gastroenterologist said a man who took a high dose developed severe diarrhea and “could have become so dehydrated with such severe electrolyte abnormalities that he could have died”37.
  • Aug 2026Case report: a man in his mid-30s with type 1 diabetes developed severe vomiting, acute kidney injury and near-ketoacidosis (ketones 4.3 mmol/L) after injecting a product bought online as retatrutide, which was not analyzed to confirm what it contained. He had skipped his insulin the day before admission because of the vomiting and fear of low blood sugar, and he also had a Shigella infection; the authors say the infection and the product’s unverified contents mean the cause cannot be established45.
  • 24 Aug 2026ABC News reported that a seventh patient in Victoria had been hospitalized for acute liver toxicity after using counterfeit retatrutide, and that Canberra’s health service had also found liver damage without saying in how many people; the TGA’s chief medical adviser said the localized pattern suggested “a batch problem” but that her comments were not the result of an investigation46.
  • 14 Sep 2026ABC News reported a TGA safety advisory: a person who used a product sold as retatrutide had uncontrollable vomiting that tore their esophagus and needed hospital treatment, and TGA tests of the unmarked vial found no retatrutide but undeclared semaglutide3054.

Questions people ask

Is retatrutide FDA approved or available yet?

No. It is an investigational drug, and Lilly plans to apply for FDA approval in the first quarter of 2027418. Outside trials, Lilly offers single-patient early access, requested by a doctor, to adults with a BMI of 35 or more whose obesity has not responded to the highest available dose of a weight-management medicine, who have at least two serious obesity-related complications and who cannot join a trial2356.

Is retatrutide a biologic?

That is still being decided. FDA refused to class it as a biological product because, by FDA’s count, retatrutide has at most 40 alpha amino acids, while its definition of a protein requires more than 40; in 2025 a court upheld that finding but sent back to FDA the question of whether retatrutide is “analogous” to a protein49. Lilly’s appeal was argued on 24 September 202650, and the Seventh Circuit’s list of opinions and orders showed no ruling as of 8 October 202662.

How much weight do people lose on retatrutide?

In TRIUMPH-1, published in September 2026, adults without diabetes lost 25.0% of body weight on 12 mg over 80 weeks versus 3.9% on placebo, counting people who stopped the drug47; by Lilly’s efficacy estimand, the figures were 28.3% versus 2.2%1. In people with type 2 diabetes, the peer-reviewed TRIUMPH-2 reported 18.8% on 12 mg versus 5.1% on placebo at 80 weeks, also counting people who stopped the drug7.

Retatrutide vs tirzepatide: what’s the difference?

Tirzepatide (Zepbound, Mounjaro) activates the GIP and GLP-1 receptors and is FDA-approved1161. Retatrutide also activates the glucagon receptor and is not approved anywhere210. A head-to-head Phase 3 trial, TRIUMPH-5, has not reported results19.

What are the side effects of retatrutide?

Gut side effects are the most common, and they rise with dose1. In the TRIUMPH-1 trial, up to 42.4% of people on retatrutide had nausea and up to 25.3% vomiting, versus 14.8% and 4.8% on placebo1. In TRIUMPH-4, up to 20.9% on the 12 mg dose had dysesthesia, abnormal skin sensations such as tingling or pain, versus 0.7% on placebo; most cases were mild6. Effects beyond about two years are unknown14.

Can I get compounded or research-use-only retatrutide?

Not legally in the US: FDA says it cannot be compounded, and selling it for human use is illegal5. Independent tests find frequent failures and mislabeling, and Victoria has linked products labeled retatrutide to liver injury389.

Is retatrutide banned in sport?

WADA does not name it, but its S0 class bans any drug with no approval anywhere, which by our reading covers retatrutide at all times32. The 2027 List, in force from 1 January 2027, adds peptides to the S0 examples33.

Who should not take retatrutide?

It is an investigational drug, not an approved one, so no label lists who should not take it4. Its largest weight-loss trial, TRIUMPH-1, did not enroll people who had ever had pancreatitis or who had a personal or family history of medullary thyroid cancer or MEN 2, an inherited condition that causes tumors in hormone-making glands, so the trial says nothing about its safety for them48.

What is still unknown

  • Full peer-reviewed results of TRIUMPH-3 and TRIUMPH-4 (we found only press releases as of 8 October 2026).
  • Whether retatrutide will be regulated as a biological product or as a drug: the Seventh Circuit had not ruled on Lilly’s appeal (argued 24 September 2026) as of 8 October 2026.
  • Effects on heart attacks, strokes and deaths; TRIUMPH-3 was inconclusive.
  • How retatrutide compares with tirzepatide head to head (TRIUMPH-5; primary completion estimated November 2026).
  • What causes dysesthesia on retatrutide, and whether it always resolves.
  • The cause of the Victorian liver-injury cluster (a contaminant is suspected, not confirmed).
  • UK Yellow Card reports: on 30 June 2026 the Daily Mail reported that the MHRA had recorded 77 reports of suspected retatrutide side effects since 2025, including one death; not checked against MHRA data.
  • Real-world effect and safety of gray-market products: the 378-person analysis is an unreviewed preprint that we saw only in summary.
  • How Finnrick derives its price-per-mg figures.
  • WADA has not ruled on retatrutide by name; the S0 status is our reading of the List.
  • Filing plans outside the US: Lilly’s releases give a timeline only for the US (first quarter of 2027), and retatrutide was not on EMA’s September 2026 list of medicines under evaluation.
  • Vendor code names such as 3G-RT and R-30 are our inference from vendor listings.

Sources

  1. 1Lilly’s triple agonist, retatrutide, delivered powerful weight loss in pivotal Phase 3 obesity trial Eli Lilly and Company (PR Newswire), 21 May 2026. prnewswire.com
  2. 2Lilly calls on online platforms, payment companies and regulators to shut down the illegal retatrutide black market Eli Lilly and Company (PR Newswire), 12 Aug 2026. prnewswire.com
  3. 3Retatrutide: vendor test results Finnrick, 29 Sep 2026. finnrick.com
  4. 4Lilly’s triple agonist, retatrutide, successful in two additional Phase 3 obesity trials, delivering significant improvements in weight and A1C Eli Lilly and Company (PR Newswire), 23 Jul 2026. prnewswire.com
  5. 5FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss U.S. Food and Drug Administration, 1 Oct 2026. fda.gov
  6. 6Lilly’s triple agonist, retatrutide, delivered weight loss of up to an average of 71.2 lbs along with substantial relief from osteoarthritis pain in first successful Phase 3 trial Eli Lilly and Company (PR Newswire), 11 Dec 2025. prnewswire.com
  7. 7Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial The Lancet, 29 Sep 2026. pubmed.ncbi.nlm.nih.gov
  8. 8New testing of black market peptides reveals dangerous dosing levels ABC News (Australia), 28 Aug 2026. abc.net.au
  9. 9Toxicity linked to unapproved peptide product labelled Retatrutide Department of Health, Victoria, 19 Jun 2026. health.vic.gov.au
  10. 10LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist for glycemic control and weight loss: From discovery to clinical proof of concept Cell Metabolism, 6 Sep 2022. pubmed.ncbi.nlm.nih.gov
  11. 11ZEPBOUND (tirzepatide) injection, for subcutaneous use: prescribing information Eli Lilly and Company via DailyMed (U.S. National Library of Medicine), 28 Aug 2026. dailymed.nlm.nih.gov
  12. 12KEGG DRUG: Retatrutide (D12430) KEGG, Kanehisa Laboratories, accessed 1 Oct 2026. kegg.jp
  13. 13LY3437943, 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 The Lancet, 26 Nov 2022. pubmed.ncbi.nlm.nih.gov
  14. 14Triple-Hormone-Receptor Agonist Retatrutide for Obesity: A Phase 2 Trial New England Journal of Medicine, 10 Aug 2023. pubmed.ncbi.nlm.nih.gov
  15. 15People Are Already Taking This Unapproved New Weight-Loss Drug WIRED, 12 Dec 2025. wired.com
  16. 16Triple G (PubChem CID 171390338) PubChem, U.S. National Library of Medicine, accessed 1 Oct 2026. pubchem.ncbi.nlm.nih.gov
  17. 17Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial The Lancet, 13 Jun 2026. pubmed.ncbi.nlm.nih.gov
  18. 18Lilly’s triple agonist, retatrutide, delivered substantial weight loss and A1C reduction, underscoring its potential promise for people with obesity and type 2 diabetes Eli Lilly and Company (PR Newswire), 29 Sep 2026. prnewswire.com
  19. 19A Study of Retatrutide (LY3437943) Compared to Tirzepatide (LY3298176) in Adults Who Have Obesity (TRIUMPH-5), NCT06662383 ClinicalTrials.gov, 20 Jul 2026. clinicaltrials.gov
  20. 20August 24, 2026: Study finds black market retatrutide is not as effective as the clinical trial versions Partnership for Safe Medicines, 24 Aug 2026. safemedicines.org
  21. 21Incretin triple agonist retatrutide (LY3437943) alleviates obesity-associated cancer progression npj Metabolic Health and Disease, 2025. pubmed.ncbi.nlm.nih.gov
  22. 22Semaglutide, tirzepatide, and retatrutide attenuate the interoceptive effects of alcohol in male and female rats Psychopharmacology, May 2026. pubmed.ncbi.nlm.nih.gov
  23. 23Lilly Expands Retatrutide Access Amid Doctor Pushback AJMC (The American Journal of Managed Care), 5 Aug 2026. ajmc.com
  24. 24Warning Letters (database search for retatrutide) U.S. Food and Drug Administration, accessed 30 Sep 2026. fda.gov
  25. 25Import Alert 66-80: Detention Without Physical Examination of GLP-1 Receptor Agonist Bulk Drug Substances U.S. Food and Drug Administration, 21 Sep 2026. accessdata.fda.gov
  26. 26Above the Federal Floor: How States Are Regulating Compounded GLP-1s and Peptides National Law Review (Sheppard Mullin), 6 Aug 2026. natlawreview.com
  27. 27Peptide therapies: popular, unproven, dangerous Partnership for Safe Medicines, 29 Jun 2026. safemedicines.org
  28. 28No summer shortcut for safe weight loss Medicines and Healthcare products Regulatory Agency (GOV.UK), 24 Jul 2026. gov.uk
  29. 29MHRA smashes major illicit weight loss medicine production facility in record seizure Medicines and Healthcare products Regulatory Agency (GOV.UK), 24 Oct 2025. gov.uk
  30. 30Patient suffers torn oesophagus after using unapproved peptide, prompting fresh warnings ABC News (Australia), 14 Sep 2026. abc.net.au
  31. 31Think twice before injecting peptides bought online: unauthorized products can seriously harm you (RA-81874) Health Canada, 9 Apr 2026. recalls-rappels.canada.ca
  32. 32World Anti-Doping Code International Standard: Prohibited List 2026 World Anti-Doping Agency, 24 Sep 2025. wada-ama.org
  33. 33World Anti-Doping Code International Standard: Prohibited List 2027 World Anti-Doping Agency, 21 Sep 2026. wada-ama.org
  34. 34Summary of Major Modifications and Explanatory Notes: 2027 Prohibited List World Anti-Doping Agency, 21 Sep 2026. wada-ama.org
  35. 35WADA publishes 2027 Prohibited List World Anti-Doping Agency, 21 Sep 2026. wada-ama.org
  36. 36Methodology Finnrick, accessed 30 Sep 2026. finnrick.com
  37. 37Vial of unapproved peptide retatrutide had double the strength indicated on label ABC News (Australia), 27 Jun 2026. abc.net.au
  38. 38Those Viral Bodega Peptides Aren’t Actually Peptides WIRED, 15 Sep 2026. wired.com
  39. 39Warning letter to NuScience Peptides LLC (MARCS-CMS 733652) U.S. Food and Drug Administration, 24 Aug 2026. fda.gov
  40. 40Warning letter to Peptide Partners LLC (MARCS-CMS 735063) U.S. Food and Drug Administration, 24 Aug 2026. fda.gov
  41. 41Welcome to the ‘peptide gray market’: where people are buying GLP-1s, Botox and filler on social media from China New York Post, 14 Jan 2026. nypost.com
  42. 42We’d Rather Buy the Future Than Wait For It Finnrick, 10 Jun 2026. finnrick.com
  43. 43r/Retatrutide (subreddit page, weekly visitor count) Reddit, accessed 30 Sep 2026. embed.reddit.com
  44. 44Google Trends: interest over time, United States, past 5 years (peptides, ozempic, retatrutide, bpc 157) Google Trends, accessed 30 Sep 2026. trends.google.com
  45. 45Online-Sourced Retatrutide Complicating Impending Diabetic Ketoacidosis in a Patient With Type 1 Diabetes and Concurrent Shigella Gastroenteritis Cureus, Aug 2026. pubmed.ncbi.nlm.nih.gov
  46. 46Doctors fear possible contaminated counterfeit peptide batch after seventh case of acute liver damage ABC News (Australia), 24 Aug 2026. abc.net.au
  47. 47Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity New England Journal of Medicine, 29 Sep 2026. pubmed.ncbi.nlm.nih.gov
  48. 48A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight (TRIUMPH-1), NCT05929066 ClinicalTrials.gov, 21 Aug 2026. clinicaltrials.gov
  49. 49Eli Lilly and Co. v. Kennedy, No. 1:24-cv-01503 (S.D. Ind.): order on cross-motions for summary judgment US District Court for the Southern District of Indiana, 30 Sep 2025. govinfo.gov
  50. 50Eli Lilly and Co. v. Kennedy, No. 26-1301 (7th Cir.): oral argument recording US Court of Appeals for the Seventh Circuit, 24 Sep 2026. media.ca7.uscourts.gov
  51. 51Mixing, Diluting, or Repackaging Biological Products Outside the Scope of an Approved Biologics License Application: Guidance for Industry US Food and Drug Administration, Jan 2018. fda.gov
  52. 52Lilly, FDA retatrutide biologic dispute comes to a head as submission nears BioSpace, 5 Aug 2026. biospace.com
  53. 53Therapeutic Goods (Poisons Standard—October 2026) Instrument 2026 (F2026L01327) Federal Register of Legislation, Australian Government, 28 Sep 2026. legislation.gov.au
  54. 54TGA tests counterfeit retatrutide product following serious adverse event report Pharmacy Today, 15 Sep 2026. pharmacytoday.co.nz
  55. 55Patient suffers torn oesophagus after counterfeit peptide use newsGP (RACGP), 14 Sep 2026. www1.racgp.org.au
  56. 56Pre-approval Expanded Access of Retatrutide (LY3437943), NCT07629401 ClinicalTrials.gov, 6 Aug 2026. clinicaltrials.gov
  57. 57Applications for new human medicines under evaluation: September 2026 (EMA/201150/2026) European Medicines Agency, 9 Sep 2026. ema.europa.eu
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  59. 59A Study of Retatrutide (LY3437943) Once Weekly in Participants Who Have Obesity or Overweight and Osteoarthritis of the Knee (TRIUMPH-4), NCT05931367 ClinicalTrials.gov, 21 Jan 2026. clinicaltrials.gov
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