First-In-Class Triple Receptor Agonist · Phase 3 Data
Retatrutide research peptide: GLP-3 RT is a retatrutide analog — a triple GIP, GLP-1, and glucagon receptor agonist — available for laboratory research from Evo Peptides. COA-verified at 99%+ purity, Wisconsin-based, same-day shipping before 3PM CST. Phase 3 TRIUMPH-4 data (Dec 2025, n=445) showed 28.7% mean weight reduction at 68 weeks.
Retatrutide
Research Peptide.
The triple receptor agonist that rewrote the Phase 3 record books. COA-verified research analog, same-day shipping from Wisconsin.
0%
Phase 3 Weight Reduction
0
Avg Weight Lost (12mg)
0%
OA Pain Reduction
3
Receptor Targets
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Mechanism of Action
Triple receptor activation.
One molecule.
Retatrutide simultaneously activates GIP, GLP-1, and glucagon receptors — the only known compound to target all three in a single molecule.
GLP-3
RT
RT
⚡
GIP
🔋
GLP-1
🔥
GCG
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GIP Receptor (GIPR)Glucose-dependent insulinotropic polypeptide receptor activation enhances insulin secretion and promotes adipogenesis regulation. Adds synergistic effect beyond GLP-1 alone.
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GLP-1 Receptor (GLP-1R)Glucagon-like peptide-1 receptor agonism drives satiety signaling, slows gastric emptying, and reduces appetite — the foundational mechanism of the incretin drug class.
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Glucagon Receptor (GCGR)Glucagon receptor activation increases energy expenditure and hepatic fat metabolism — the third target that differentiates retatrutide from all dual-receptor agonists including tirzepatide.
Clinical Evidence
TRIUMPH Phase 3 program.
The data.
Eli Lilly’s largest obesity Phase 3 program to date. 8 trials, 25,000+ participants, $3.5B manufacturing commitment.
28.7%
Mean body weight reduction at 68 weeks (12mg dose)
TRIUMPH-4, Dec 2025 · NCT05931367 · n=445
71.2 lbs
Average weight lost — highest Phase 3 signal ever recorded for a GLP-1 class compound
Eli Lilly press release · Dec 11, 2025
75.8%
Reduction in WOMAC knee osteoarthritis pain scores
TRIUMPH-4 secondary endpoint · Dec 2025
25,000+
Total participants enrolled across all TRIUMPH, TRANSCEND & SYNERGY Phase 3 trials
Retatrutide.med · March 2026
Phase 2 Foundation — NEJM 2023
24.2%
Weight reduction at 48 weeks (12mg, Phase 2)
100%
of 12mg participants achieved ≥5% weight reduction at 48 weeks
338
Participants enrolled (Jastreboff et al., NEJM 2023)
n=6
Dose groups studied (1mg through 12mg + placebo)
Source: Jastreboff AM et al. “Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial.” N Engl J Med. 2023;389(6):514-526. DOI: 10.1056/NEJMoa2301972
TRIUMPH Program Timeline
P2
June 26, 2023
Phase 2 Results — NEJM Publication
24.2% weight reduction at 48 weeks (12mg). 100% of participants achieved ≥5% weight loss. Simultaneous presentation at ADA 83rd Scientific Sessions.
Complete
P3
December 11, 2025
TRIUMPH-4 Phase 3 — First Readout
28.7% weight reduction at 68 weeks. 75.8% OA pain reduction. Largest Phase 3 weight loss signal ever recorded for a GLP-1 class compound. NCT05931367, n=445.
Complete · Eli Lilly Press Release
P3
Q2–Q3 2026 (Expected)
TRIUMPH-1 Readout — Primary NDA Trial
80-week primary weight management trial in general obesity population without T2D. Designed as direct comparator to SURMOUNT-1 (tirzepatide) and STEP-1 (semaglutide).
Active · NCT05614752
6+
2026
6 Additional Phase 3 Readouts Expected
TRIUMPH-2 (obesity + T2D), TRIUMPH-3 (Class II/III obesity + CVD), TRANSCEND T2D program (3 trials), SYNERGY MASLD/MASH. Total program: 19 trials, 25,000+ participants.
Pending
Compound Comparison
Retatrutide vs. tirzepatide vs. semaglutide.
Published data only.
All figures from published Phase 2 or Phase 3 randomized controlled trials. No marketing claims.
| Metric | Retatrutide (GLP-3 RT) | Tirzepatide (GLP-2 TRZ) | Semaglutide |
|---|---|---|---|
| Receptor targets | GIP + GLP-1 + Glucagon (3) | GIP + GLP-1 (2) | GLP-1 only (1) |
| Best Phase 3 weight reduction | 28.7% at 68 wks (TRIUMPH-4) | 20.9% at 72 wks (SURMOUNT-1) | 14.9% at 68 wks (STEP-1) |
| Average lbs lost (12mg/2.4mg) | 71.2 lbs | ~52 lbs | ~34 lbs |
| Key Phase 3 trial | TRIUMPH-4 (Dec 2025) | SURMOUNT-1 (NEJM 2022) | STEP-1 (NEJM 2021) |
| FDA approval status | Phase 3 ongoing (NDA ~2026) | FDA approved (May 2022) | FDA approved (Jun 2021) |
| Evo Peptides research analog | GLP-3 RT — from $74.95 | GLP-2 TRZ — $64.95 | Not carried |
Sources: TRIUMPH-4 (Eli Lilly, Dec 2025) · SURMOUNT-1 (NEJM 2022, Jastreboff et al.) · STEP-1 (NEJM 2021, Wilding et al.) · All compounds sold for research use only.
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GLP-3 RT — Retatrutide research analog.
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GLP-3 RT
Retatrutide Analog · Triple GIP/GLP-1/GCG Receptor Agonist · COA-Verified
- ✓Triple receptor activity — GIP, GLP-1 & glucagon
- ✓15mg and 30mg vials available
- ✓COA-verified 99%+ purity by independent lab
- ✓Lyophilized powder, research grade
- ✓Same-day shipping before 3PM CST
- ✓Wisconsin-based, US domestic only
- ✓Free shipping on orders over $100
15mg vial
$74.95
$104.95
Save 29%
30mg vial
$129.95
$159.95
Save 19%
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Research Context
The retatrutide landscape.
$3.5B
Lilly manufacturing investment
Eli Lilly committed $3.5 billion to expand manufacturing capacity in anticipation of potential retatrutide approval, signaling high commercial confidence in the compound.
Retatrutide.med · March 2026
8
Active Phase 3 trials
TRIUMPH (obesity), TRANSCEND (T2D), and SYNERGY (MASLD/MASH) programs across 19 total trials. At least 6 additional readouts expected in 2026 following TRIUMPH-4.
Eli Lilly TRIUMPH program overview · 2026
~2027
Projected FDA NDA timeline
Pending positive TRIUMPH-1 readout (expected Q2–Q3 2026), Lilly is expected to submit an NDA to the FDA and MAA to the EMA. Regulatory review typically takes 12+ months.
Retatrutide.med · March 2026 · Analyst consensus
FAQ
Retatrutide research questions.
Frequently asked questions about retatrutide mechanism, trial data, and research sourcing.
Retatrutide (LY3437943) is a first-in-class investigational once-weekly triple hormone receptor agonist developed by Eli Lilly that simultaneously activates GIP, GLP-1, and glucagon receptors. It is the only known compound to activate all three receptor types in a single molecule, producing synergistic metabolic effects beyond single or dual receptor agonists. Phase 3 data from TRIUMPH-4 (December 2025) showed 28.7% weight reduction at 68 weeks — the largest Phase 3 signal ever recorded for a GLP-1 class compound.
TRIUMPH-4 (NCT05931367, n=445) reported in December 2025 that retatrutide 12mg produced 28.7% mean body weight reduction at 68 weeks — equivalent to an average 71.2 lbs. Secondary findings included a 75.8% reduction in WOMAC knee osteoarthritis pain scores, with more than 1 in 8 treated patients completely free from knee pain at trial end. Cardiovascular risk markers including non-HDL cholesterol and systolic blood pressure were also reduced.
Based on published Phase 3 data: Retatrutide showed 28.7% weight reduction at 68 weeks (TRIUMPH-4, Dec 2025). Tirzepatide showed up to 20.9% at 72 weeks (SURMOUNT-1, NEJM 2022). Semaglutide showed 14.9% at 68 weeks (STEP-1, NEJM 2021). Retatrutide’s superior signal is attributed to its unique glucagon receptor activation — a third target absent from tirzepatide — which increases energy expenditure and hepatic fat metabolism in addition to the satiety effects of GIP/GLP-1 dual agonism.
GLP-3 RT is Evo Peptides’ retatrutide research analog — a triple GIP/GLP-1/glucagon receptor agonist peptide for laboratory and in-vitro research. Available in 15mg ($74.95) and 30mg ($129.95) vials. COA-verified at 99%+ purity by an independent third-party lab. Sold for research use only, not for human consumption. Same-day shipping on orders before 3PM CST from Wisconsin. Order at evopeptidesus.com/product/glp-3-rt/
Eli Lilly is running 19 trials across three Phase 3 programs: TRIUMPH (obesity/overweight — 5 active trials plus TRIUMPH-Outcomes CVOT enrolling 10,000 patients), TRANSCEND (type 2 diabetes — 3 trials), and SYNERGY (MASLD/MASH liver disease). Total enrollment exceeds 25,000 participants. TRIUMPH-4 reported in December 2025; at least 6 additional readouts are expected in 2026, including TRIUMPH-1 — the primary obesity NDA-anchoring trial.
No. As of May 2026, retatrutide is not FDA approved and remains an investigational compound in Phase 3 clinical trials. Pending positive readout from TRIUMPH-1 (expected Q2–Q3 2026), Eli Lilly is expected to submit an NDA to the FDA and MAA to the EMA. Regulatory review typically takes 12+ months. GLP-3 RT is sold by Evo Peptides exclusively as a Research Use Only (RUO) research peptide — not for human consumption or clinical use.
Order GLP-3 RT today.
COA-verified retatrutide analog. Same-day shipping before 3PM CST from Wisconsin. Free shipping on orders over $100.
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For Research Use Only. GLP-3 RT is sold exclusively for laboratory and in-vitro research purposes. It is not intended for human or veterinary consumption, diagnosis, treatment, or prevention of any disease. Evo Peptides is not affiliated with Eli Lilly and Company. Retatrutide (LY3437943) is an investigational compound not approved by the FDA. These statements have not been evaluated by the FDA. Evo Peptides is not a compounding pharmacy. All clinical trial data referenced is sourced from published peer-reviewed journals and official company press releases. © 2026 Evo Peptides · Wisconsin, USA.