Retatrutide
Checked Oct 11, 2026 · 14 sources checked
Retatrutide is an experimental once-weekly injection from Eli Lilly that activates three hormone receptors: GIP, GLP-1 and glucagon. It is often called a "triple agonist". Adding glucagon-receptor activity is meant to raise energy use on top of the appetite effects of GLP-1-type drugs. Retatrutide is not approved by the FDA for any use. The FDA says it has not been found safe and effective for any condition and cannot legally be used in compounding. The FDA has also warned companies selling it as a "research" product. Two phase 3 trials in obesity were published in 2026. Trials of its long-term effects on the heart and kidneys are still running. Lilly says it plans to apply for US approval in early 2027 (company-reported).
Education only, not medical advice. Talk to a clinician about your own situation.
Attention is high. English Wikipedia's Retatrutide article had 39,578, 35,065 and 35,139 views in July, August and September 2026, comparable to semaglutide. PubMed added 20 records in the 30 days to Oct 11 2026, against about 10.3 a month in the preceding 90 days (31 records). NBC News covered the TRIUMPH-2 results on 2026-09-29. Three independent publishers (Wikimedia, NLM, NBC News) give dated receipts, which meets the two-publisher bar for a heat label. We still propose none: pageviews are flat, and the PubMed rate (1.9 times baseline) is just under the intake rule's 2x velocity threshold. Editor's call.
In adults with obesity and no diabetes, weekly retatrutide reduced body weight by 23.7% and 25.0% on average at its two higher doses over 80 weeks, versus 3.9% with placebo. It also reduced knee-osteoarthritis pain and sleep-apnea events in the subgroups that had those conditions.
For adults with obesity and cardiovascular or kidney disease, does retatrutide reduce heart attacks, strokes and kidney decline, and is it safe beyond two years?
If TRIUMPH-Outcomes (NCT06383390) shows no reduction in major cardiovascular or kidney events, or shows an excess of serious harm, our summary would say the weight loss has not translated into better hard outcomes, or that it carries that harm.
If TRIUMPH-5 (NCT06662383) shows no significant difference from tirzepatide in weight loss, we would describe the two drugs as similar on that endpoint rather than ranking them.
Word on the street
Who's covering it lately. Coverage means people are talking about it; it isn't evidence, and it never changes our read.
- The Washington Post · Oct 9, 2026Read the coverage ↗
- CBS News · Sep 30, 2026Read the coverage ↗
- NBC News · Sep 29, 2026Read the coverage ↗
- The Guardian · Sep 29, 2026Read the coverage ↗
For the pros: claims, studies and receipts14 sources · tap to open
4 reviewed claim records · 14 linked source receipts Inspect source receipts
Maturity: source checked
In adults with obesity and no diabetes, weekly retatrutide reduced body weight by 23.7% and 25.0% on average at its two higher doses over 80 weeks, versus 3.9% with placebo. It also reduced knee-osteoarthritis pain and sleep-apnea events in the subgroups that had those conditions.
Adults with obesity, without diabetes (subgroups with knee OA and OSA) · Outcome: Percent change in body weight; WOMAC pain (knee OA subgroup); AHI (OSA subgroup)Confidence applies to this claim and context.
Identity
Metabolic / obesity · active ingredient
Identity checked Oct 7, 2026. This establishes the catalog name; evidence assessment is separate.
LY3437943 · development code
Checked facts
- In adults with obesity and no diabetes, weekly retatrutide reduced body weight by 23.7% and 25.0% on average at its two higher doses over 80 weeks, versus 3.9% with placebo. It also reduced knee-osteoarthritis pain and sleep-apnea events in the subgroups that had those conditions. PMID 42814954 ↗
- In adults with obesity and type 2 diabetes, retatrutide reduced body weight by 11.9% to 18.8% on average across three doses over 80 weeks, versus 5.1% with placebo, and improved blood-sugar control. Gastrointestinal side effects, low blood pressure and dysesthesia (abnormal skin sensations) were more common with retatrutide than placebo (dysesthesia 4-7% vs 1%). Stopping treatment because of side effects was more common at the two higher doses (12% and 8%, vs 5% on placebo). PMID 42810372 ↗
- In adults with type 2 diabetes not controlled by diet and exercise, retatrutide lowered HbA1c by 0.88 to 1.12 percentage points more than placebo, depending on dose. PMID 42250575 ↗
- In the earlier phase 2 trial in adults with obesity, weight fell by up to 24.2% on average at 48 weeks with retatrutide, versus 2.1% with placebo. Gastrointestinal side effects were the most common and were dose-related. Heart rate rose with dose, peaking at 24 weeks. PMID 37366315 ↗
Attention describes reviewed public attention, evidence shows study types, and confidence applies only to the stated claim. There is no overall score.
Claims
Would change this claim: If TRIUMPH-Outcomes (NCT06383390) shows no reduction in major cardiovascular or kidney events, or shows an excess of serious harm, our summary would say the weight loss has not translated into better hard outcomes, or that it carries that harm.
Source: Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity. · PMID 42814954 · N Engl J Med · Abstract, Results: -23.7% and -25.0% (two higher doses) vs -3.9%; differences -19.8 and -21.0 points · Verify ↗Source: A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight · NCT NCT05929066 · Eli Lilly and Company · Abstract, Results: -23.7% and -25.0% (two higher doses) vs -3.9%; differences -19.8 and -21.0 points · Verify ↗Mapped studies / experiment families
One experiment counts once, even with several registrations or publications. Counts above describe the headline claim.
No reviewed experiment families mapped yet.
Studies & active trials
Only papers and registered trials an editor reviewed for this page. Being listed is not a finding; the claims above say what they show.
What still isn't settled?
For adults with obesity and cardiovascular or kidney disease, does retatrutide reduce heart attacks, strokes and kidney decline, and is it safe beyond two years?
The published phase 3 trials ran 80 weeks and measured weight and related outcomes, not cardiovascular or kidney events. Lilly's topline results from TRIUMPH-3 (about 1,950 adults with severe obesity and cardiovascular disease; not yet peer-reviewed) reported too few cardiovascular events to draw conclusions (27 vs 23 heart attacks, strokes or cardiovascular deaths; hazard ratio 1.12, 95% CI 0.64-1.96; company-reported).
What would answer it: Results of TRIUMPH-Outcomes (NCT06383390), an event-driven placebo-controlled trial in about 10,000 adults with BMI ≥27 and cardiovascular and/or chronic kidney disease (estimated primary completion 2029-02). It reports major cardiovascular and kidney events, plus adverse-event data from treatment beyond two years.
Shown in phase 3 trials: weight loss versus placebo over 80 weeks in adults without diabetes (TRIUMPH-1, NEJM 2026) and with type 2 diabetes (TRIUMPH-2, Lancet 2026).