The clinical data on retatrutide continues to build at a remarkable pace. Following the landmark TRIUMPH-4 readout in December 2025 — which reported a mean weight loss of 28.7% over 68 weeks, the highest ever recorded in a Phase 3 obesity trial — Eli Lilly has now announced two additional positive Phase 3 results from the TRIUMPH program. The TRIUMPH-2 and TRIUMPH-3 trials represent the fourth and fifth positive Phase 3 readouts for retatrutide, adding substantially to an evidence base that already distinguishes this drug as one of the most consequential advances in obesity medicine in decades. The following summary draws on data shared in Eli Lilly's investor press release announcing these results.
TRIUMPH-2 specifically enrolled adults living with obesity or overweight alongside type 2 diabetes — a population that has historically proven more difficult to treat with weight loss medications. Metabolic disease tends to blunt the response to many agents, and expectations in this group are often set lower as a result.
The results challenged that assumption. Adults in TRIUMPH-2 lost an average of 49.6 pounds, representing a mean body weight reduction of approximately 20.8%, over 80 weeks of treatment. For context, the Phase 2 retatrutide trial — which excluded participants with type 2 diabetes — showed mean weight reductions of up to 24.2% at 48 weeks in the highest-dose group. That TRIUMPH-2 approached comparable territory in a population with diabetes, and over a longer treatment horizon, is clinically meaningful.
Beyond weight, the trial also measured glycemic outcomes. Retatrutide is a triple agonist, activating receptors for GLP-1, GIP, and glucagon simultaneously. The GLP-1 and GIP components drive meaningful improvements in blood sugar regulation, which made TRIUMPH-2's A1C data particularly important. Significant A1C reductions were observed alongside the weight loss, offering a dual benefit that is directly relevant to patients managing both conditions.
In patient communities, retatrutide is commonly referred to as reta, and the drug's mechanism — sometimes called triple G shorthand for its triple agonist action — is frequently cited as the reason it appears to outperform dual agonists in head-to-head trend comparisons. The simultaneous engagement of the glucagon receptor, which is not targeted by semaglutide or tirzepatide, is believed to contribute to enhanced energy expenditure and the robust fat loss observed across TRIUMPH trials.
TRIUMPH-3 enrolled a distinct and high-risk population: adults with severe obesity and established cardiovascular disease, with or without type 2 diabetes. This is precisely the population in which the stakes of effective obesity treatment are highest. Excess adiposity drives inflammation, hemodynamic stress, and metabolic dysfunction that compound cardiovascular risk at every level.
According to the Lilly press release, TRIUMPH-3 also met its primary endpoints, demonstrating statistically significant and clinically meaningful weight reduction in this complex group. While granular weight loss percentages from TRIUMPH-3 had not been published in peer-reviewed form at the time of the announcement, the positive readout confirms that retatrutide's efficacy extends to patients with significant cardiometabolic burden — not only the healthier-baseline participants more commonly enrolled in Phase 2 studies.
The inclusion of patients with and without type 2 diabetes in TRIUMPH-3 further broadens the applicability of these results. It suggests that retatrutide's benefit is not confined to any single metabolic phenotype, and that the cardiovascular population — one with enormous unmet need — may derive substantial weight-related and potentially cardioprotective benefit from this therapy.
The Phase 2 trial published in the New England Journal of Medicine in 2023 (Jastreboff et al.) established the foundational efficacy and safety profile for retatrutide. That 48-week, double-blind, placebo-controlled study enrolled 338 adults without type 2 diabetes and tested once-weekly subcutaneous doses of 1mg, 4mg, 8mg, and 12mg. The results were striking even then.
| Trial / Drug | Population | Duration | Mean Weight Loss | Notable Threshold |
|---|---|---|---|---|
| Retatrutide Phase 2 (12mg) | Obesity, no T2D | 48 weeks | ~24.2% | 48% lost ≥25% body weight |
| Retatrutide TRIUMPH-4 (12mg) | Obesity, no T2D | 68 weeks | 28.7% | Highest Phase 3 result on record |
| Retatrutide TRIUMPH-2 (12mg) | Obesity + Type 2 Diabetes | 80 weeks | ~20.8% (49.6 lbs) | Significant A1C reduction |
| Tirzepatide SURMOUNT-1 (15mg) | Obesity, no T2D | 72 weeks | 20.9% | Dual GLP-1/GIP agonist |
| Semaglutide STEP-1 (2.4mg) | Obesity, no T2D | 68 weeks | ~14.9% | GLP-1 single agonist |
What the table makes clear is a consistent dose-response and mechanism-response pattern. As receptor targets increase from one to two to three, mean weight loss figures climb accordingly. Retatrutide's glucagon receptor engagement appears to be the key differentiator, supporting energy expenditure beyond what appetite suppression alone can achieve. The Phase 2 data also showed that 100% of participants in the 8mg group achieved at least 5% weight loss at 48 weeks — a threshold that would have been considered an ambitious benchmark for any single agent a decade ago.
The lipid improvements seen in Phase 2 are also worth noting. At 24 weeks, participants receiving 12mg saw fasting triglycerides fall by 34.0% and total cholesterol by 17.3%, with LDL reductions of approximately 15.6% to 16.9% in the 8mg group. These are effects that matter clinically, particularly in the cardiovascular disease population enrolled in TRIUMPH-3.
For the tens of thousands of people tracking retatrutide's regulatory progress, TRIUMPH-2 and TRIUMPH-3 represent meaningful forward momentum. Five positive Phase 3 trials across diverse populations — including adults without diabetes, adults with type 2 diabetes, and adults with cardiovascular disease — establish a body of evidence that is broad, consistent, and compelling. These results collectively address the populations most likely to need effective pharmacotherapy for obesity and metabolic disease.
The common experience of food noise — the persistent, intrusive preoccupation with eating that makes behavioral approaches alone so difficult to sustain — is addressed by retatrutide's central and peripheral mechanisms in ways that patients across trials have consistently described as transformative. The combination of appetite regulation, metabolic enhancement through glucagon receptor activation, and meaningful improvements in cardiometabolic markers positions this triple agonist as a genuinely differentiated therapy.
It is important to note that retatrutide has not yet received FDA approval, and no NDA had been filed as of April 2026. Peer-reviewed publications for the Phase 3 TRIUMPH trials remain pending. The path from Phase 3 success to regulatory approval involves additional steps, and timelines are not publicly confirmed.
Staying informed is the most practical step available right now. glp3md.com maintains a waitlist for individuals who want to be among the first notified as retatrutide moves through the regulatory process. Joining the waitlist does not guarantee access to medication, treatment, or a prescription — retatrutide is not approved, and no promises about future availability can be made. What it does provide is timely, clinically grounded updates as this therapy advances. Visit glp3md.com to add your name and stay current on one of the most closely watched developments in obesity medicine today.
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Join the WaitlistThis article is for educational purposes only and does not constitute medical advice. Retatrutide is an investigational drug and is not FDA approved as of publication. Clinical data referenced is from publicly available trial publications. Consult a qualified healthcare provider before making any treatment decisions.