Retatrutide TRIUMPH-2 & TRIUMPH-3 Results: 22.6% Weight Loss, Open Questions on Heart Benefit

What Lilly Announced on July 23, 2026

On July 23, 2026, Eli Lilly reported positive topline results from two more Phase 3 studies in its TRIUMPH trial program for retatrutide, its investigational triple-agonist (GLP-1/GIP/glucagon) peptide. TRIUMPH-2 tested retatrutide in adults with type 2 diabetes and obesity. TRIUMPH-3 tested it in adults with severe obesity and established cardiovascular disease. Both hit their primary weight-loss endpoints (Eli Lilly, July 23, 2026).

Alongside the data, Lilly reaffirmed that it plans to file a Biologics License Application (BLA) with the FDA in Q1 2027 (Reuters, July 23, 2026). Kenneth Custer, Lilly's EVP of Cardiometabolic Health, summed up the company's framing: "Across five positive Phase 3 studies, retatrutide has shown powerful efficacy, and we believe it could be an important future tool in the management of cardiometabolic health" (Eli Lilly, July 23, 2026).

That's the corporate framing, and it's not wrong — the weight-loss numbers are genuinely strong across five different patient populations now. But nearly every outlet that covered this news led with the 22.6% number and moved on. Almost none of them lingered on what the cardiovascular data actually shows, or explained why the honest answer to "does retatrutide protect the heart?" is still "we don't know." That's the gap this article fills. Both framings matter here — the encouraging one and the unresolved one — and a patient or clinician deciding what to do next needs both.

TRIUMPH-2: Retatrutide in Type 2 Diabetes + Obesity

TRIUMPH-2 enrolled 1,152 adults with type 2 diabetes and obesity or overweight. At baseline, participants averaged 106.4 kg (234.6 lbs) with a BMI of 38.2 and an HbA1c of 7.7%. Over 80 weeks, retatrutide produced dose-dependent weight loss and meaningful glycemic control across all three doses tested (Eli Lilly, July 23, 2026; ClinicalTrials.gov, NCT05929079).

Dose	Weight loss (%)	Weight loss (lbs)	HbA1c reduction	AE discontinuation
4 mg	-12.7%	-29.8 lbs	-1.4 pts	3.8%
9 mg	-19.1%	-45.4 lbs	-1.6 pts	11.6%
12 mg	-20.8%	-49.6 lbs	-1.5 pts	7.7%
Placebo	—	—	-0.2 pts	4.9%

A few things worth noting in this table. First, the HbA1c reduction does not track linearly with dose — the 9 mg group actually posted a slightly larger glycemic improvement (-1.6 points) than the 12 mg group (-1.5 points), even though 12 mg produced more weight loss. That's a real result, not a typo, and it's a reminder that weight loss and glycemic control, while correlated, are not the same lever. Second, the AE discontinuation rate at 9 mg (11.6%) was actually higher than at 12 mg (7.7%) — an unusual pattern that Lilly hasn't fully explained publicly, though it may reflect the specific titration schedule used in this trial's protocol. Third, and more predictably: gastrointestinal side effects (nausea, diarrhea, constipation) remained the dominant tolerability issue across all doses, consistent with the rest of the GLP-1 class. For a full breakdown of what to expect tolerability-wise, see our guide to retatrutide side effects.

For context, the -1.5 to -1.6 percentage point HbA1c reduction at the top doses is competitive with — but not clearly superior to — what tirzepatide has shown in its SURPASS trial program for type 2 diabetes. Retatrutide's edge in this population appears to be more about weight loss magnitude than glycemic control magnitude.

TRIUMPH-3: Retatrutide in Severe Obesity + Cardiovascular Disease

TRIUMPH-3 is the larger and, for the purposes of this article, more consequential trial. It enrolled 1,949 adults with severe obesity (average BMI 40.4) and established cardiovascular disease — baseline weight averaged 111.4 kg (245.6 lbs). This is the population where Lilly needed retatrutide to show not just weight loss, but a favorable cardiovascular risk profile (Eli Lilly, July 23, 2026; ClinicalTrials.gov, NCT05882045).

Measure	9 mg	12 mg	Placebo
Weight loss (%)	-21.6%	-22.6%	-3.2%
Weight loss (lbs)	-52.7 lbs	-55.8 lbs	-7.7 lbs
Triglycerides	—	-37.0%	—
Non-HDL cholesterol	—	-16.5%	—
Systolic blood pressure	—	-9.3 mmHg	—
Waist circumference	—	-7.5 in	—
hsCRP (inflammation)	—	-51.2%	—
AE discontinuation	9.8%	13.5%	4.8%

The risk-factor improvements here are genuinely strong: a 37% drop in triglycerides and a halving of hsCRP (a marker of systemic inflammation linked to cardiovascular risk) are the kind of numbers that make a biological case for retatrutide helping cardiovascular health indirectly, through weight loss and metabolic improvement. But risk-factor improvement is not the same thing as proven event reduction, and that distinction is the crux of the next section.

It's also worth being honest about the 13.5% discontinuation rate at the 12 mg dose due to adverse events. That's a real number with real-world implications — roughly one in seven patients on the highest dose in this population stopped treatment because of side effects. That's not dramatically different from what's been seen at high doses elsewhere in the retatrutide program, and largely GI-driven, but it's not nothing either. For more on the tolerability pattern across doses, see our retatrutide side effects breakdown.

The Cardiovascular Question: What the Data Actually Shows

This is the section that matters most, and it's the one most coverage skipped past. TRIUMPH-3 included a Major Adverse Cardiovascular Events (MACE) analysis, and it reported two different versions of it — a broader one and a narrower one — with two different directional results. Understanding both, and understanding why neither is proof of anything, is the whole point of this article.

MACE-5: the broader composite

MACE-5 counts cardiovascular death, heart attack (MI), stroke, heart failure hospitalization, and coronary revascularization. In TRIUMPH-3, there were 44 MACE-5 events in the retatrutide group (pooled 9 mg and 12 mg) versus 52 in the placebo group. That works out to a hazard ratio of 0.82, with a 95% confidence interval of 0.55 to 1.22 (STAT News, July 23, 2026; Fierce Biotech, July 23, 2026). The direction favors retatrutide — fewer events on the drug than on placebo — but the confidence interval crosses 1.0, which means the result is not statistically significant.

MACE-3: the narrower, more clinically decisive composite

MACE-3 counts only cardiovascular death, non-fatal heart attack, and non-fatal stroke — the endpoint regulators and cardiologists generally weight most heavily because it's less prone to reporting variability than broader composites. Here, the picture flips: 27 events on retatrutide versus 23 on placebo, a hazard ratio of 1.12, with a 95% confidence interval of 0.64 to 1.96. That's directionally worse for retatrutide — more events on the drug than on placebo — though, again, the wide confidence interval crosses 1.0, so it is not statistically significant either.

What a hazard ratio and confidence interval actually mean

In plain terms: a hazard ratio (HR) compares the rate of events between two groups. An HR of 1.0 means no difference. An HR below 1.0 means fewer events in the treatment group (a good sign); above 1.0 means more events in the treatment group (a concerning sign). The confidence interval (CI) is the range of hazard ratios consistent with the data — think of it as the margin of error. When that range includes 1.0, as both of these do, statisticians say the result is "not statistically significant," meaning the study cannot rule out that there's truly no difference between the drug and placebo. It also can't rule out a real benefit or a real harm — the study simply doesn't have enough events to tell.

That "not enough events" problem is the heart of it. Lilly's own explanation is that "the trial was not powered to study cardiovascular outcomes; fewer heart events than anticipated" occurred during the trial (BioPharma Dive, July 23, 2026). "Not powered" is a specific statistical term — it means the trial wasn't designed, sized, or run long enough to reliably detect a true difference in cardiovascular events, even if one exists. TRIUMPH-3 was primarily a weight-loss and risk-factor trial that happened to also track MACE; it was never built to be a cardiovascular outcomes trial. That's a legitimate explanation, not spin — but it also means neither number, the reassuring MACE-5 or the concerning MACE-3, can be treated as evidence of anything definitive.

Two honest framings of the same data

Bloomberg's coverage emphasized the reassuring read: retatrutide "didn't increase overall heart risk" in the trial (Bloomberg, July 23, 2026) — a framing anchored in the MACE-5 result and Lilly's broader efficacy narrative. STAT News took the more cautious line, reporting that the new data "leave open questions on heart benefit" and that the results "aren't enough to answer a critical question about the therapy — whether it reduces cardiovascular risk" (STAT News, July 23, 2026). Fierce Biotech was blunter still, headlining that the "cardio risk impact disappoints" even while celebrating the weight-loss number (Fierce Biotech, July 23, 2026).

Both framings are accurate. Bloomberg isn't wrong that the topline MACE-5 result doesn't show harm. STAT isn't wrong that the trial doesn't answer the question cardiologists actually need answered. The two framings simply emphasize different endpoints from the same underlying, statistically inconclusive dataset. If you only read one outlet's headline, you got half the picture.

How this compares to Wegovy's SELECT trial

The most useful comparison point is semaglutide's SELECT trial, published in 2023. SELECT enrolled roughly 17,000 patients with established cardiovascular disease (without diabetes) specifically to answer the MACE question, and it was powered and run long enough to do so. The result: a statistically significant 20% reduction in major adverse cardiovascular events, hazard ratio 0.80. That result is why Wegovy carries an FDA-recognized cardiovascular risk-reduction label today.

TRIUMPH-3 was roughly one-ninth the size of SELECT and wasn't event-driven in the same way. It simply could not generate a statistically decisive answer on cardiovascular outcomes, regardless of which direction the numbers pointed. That's the honest read: retatrutide has not replicated Wegovy's cardiovascular proof, and TRIUMPH-3 was never going to be the trial that could. For the full underlying trial design and endpoints, see TRIUMPH-3's cardiovascular outcomes analysis.

Why 22.6% Is Lower Than the Earlier 28.7% (TRIUMPH-1)

An earlier retatrutide readout — the TRIUMPH-1 general obesity trial, and its Phase 2 extension data — put the ceiling number at 28.7% weight loss. TRIUMPH-3's 22.6% and TRIUMPH-2's 20.8% understandably read, at first glance, like a step down. They are not a sign that retatrutide is losing potency or that something went wrong.

The explanation is population selection, and it's a pattern seen across the entire GLP-1 drug class, not something unique to retatrutide. People with type 2 diabetes lose less weight on GLP-1 class drugs than people without diabetes, likely due to differences in insulin sensitivity and metabolic adaptation. People with established cardiovascular disease tend to be older, have more comorbidities, and are often on medications (beta blockers, for instance) that can blunt weight-loss response. TRIUMPH-2 enrolled a type 2 diabetes population; TRIUMPH-3 enrolled a cardiovascular disease population. TRIUMPH-1, by contrast, enrolled a general obesity population without those complicating factors — which is exactly why it produced the higher number.

Trung Huynh, an analyst at RBC Capital Markets, made this point directly, noting that the newer results "met expectations for patients with underlying conditions who often lose less weight" (BioPharma Dive, July 23, 2026). William Blair's research team characterized the 22.6% figure as "slightly below the 28.7% peak seen in an earlier retatrutide trial" — an observation, not a warning sign.

The practical takeaway: if you're comparing retatrutide's efficacy across populations, always check which population the number comes from. A general-obesity number and a type-2-diabetes-plus-cardiovascular-disease number are not directly comparable, and neither is a "disappointment" relative to the other — they're both consistent with what's already known about how comorbidities affect GLP-1 response.

The Study That Will Actually Answer the CV Question: TRIUMPH-Outcomes

If TRIUMPH-3 can't answer whether retatrutide reduces cardiovascular events, what will? That's TRIUMPH-Outcomes (NCT06383390) — a dedicated, purpose-built cardiovascular outcomes trial that is a completely separate study from TRIUMPH-3 (ClinicalTrials.gov, NCT06383390).

Here's what makes TRIUMPH-Outcomes different, and why it's designed to succeed where TRIUMPH-3 structurally could not:

• Scale: approximately 10,000 participants, more than five times the size of TRIUMPH-3.
• Population: adults with BMI ≥27 and established atherosclerotic cardiovascular disease (ASCVD) and/or chronic kidney disease (CKD) — a population selected specifically to generate enough cardiovascular events for a statistically decisive answer.
• Design: Phase 3, randomized, double-blind, placebo-controlled, and — critically — event-driven, meaning the trial runs until a pre-specified number of cardiovascular events has occurred, rather than stopping at a fixed calendar date. This is the same design logic that made SELECT statistically decisive.
• Primary endpoint: time to first MACE-3 event (cardiovascular death, non-fatal heart attack, non-fatal stroke) — the same narrower, more clinically decisive endpoint TRIUMPH-3 could only look at underpowered.
• Secondary endpoint: cardiovascular death or heart failure hospitalization.
• Duration: up to 248 weeks (roughly 4.7 years).
• Primary completion date: February 2029.
• Status: active, not recruiting, as of the last ClinicalTrials.gov update (April 20, 2026).

That February 2029 date is the single most important number in this article for anyone weighing whether to wait for retatrutide specifically because of its heart. Retatrutide's most likely FDA approval window, based on the confirmed Q1 2027 BLA filing and standard review timelines, is late 2027 to early 2028 (see our retatrutide FDA approval date analysis for the full scenario breakdown). That means retatrutide will likely be commercially available for roughly a year or two before the dedicated cardiovascular outcomes trial even finishes collecting its primary data. Patients and clinicians deciding whether to prescribe or take retatrutide specifically for cardiovascular protection will be doing so without that proof in hand — for at least the first couple of years after launch.

This is worth restating plainly because it rarely gets said outside specialist coverage: approval does not equal cardiovascular proof. The FDA can approve retatrutide for weight management or type 2 diabetes based on the efficacy data already in hand, while the cardiovascular benefit question — the thing that determines whether cardiologists confidently reach for it the way they now reach for Wegovy — stays open until the long-term CV outcomes study reports results in 2029.

How Retatrutide Compares to What's Already Approved

Placing retatrutide's TRIUMPH-2 and TRIUMPH-3 results next to the two GLP-1-class drugs already on pharmacy shelves clarifies what's actually different here — and what isn't.

Wegovy (semaglutide) already has the cardiovascular proof retatrutide lacks. The SELECT trial gave it a statistically significant, FDA-recognized cardiovascular risk-reduction label. Its weight-loss efficacy, however, tops out well below retatrutide's — typically in the mid-teens percentage range at the highest dose, versus retatrutide's 20%+ in comparable populations. See our detailed retatrutide vs semaglutide comparison for the full efficacy and mechanism breakdown.

Zepbound (tirzepatide) is the closer efficacy competitor. Its SURMOUNT trial program has shown roughly 21% weight loss in general obesity populations — in the same range as retatrutide's TRIUMPH-3 result, though TRIUMPH-3 enrolled a harder-to-treat cardiovascular disease population, which makes retatrutide's number more impressive in context. Tirzepatide does not currently carry a cardiovascular benefit label either, though its own outcomes trial (SURMOUNT-MMO) is underway. See our full retatrutide vs tirzepatide comparison.

The net picture: retatrutide will very likely launch as the highest-efficacy weight-loss option among the three, but without a cardiovascular benefit claim — a gap Wegovy has already closed and Zepbound is still working to close.

What This Means for Different Patient Populations

The right way to think about these results depends heavily on why someone is interested in retatrutide in the first place.

If you want the largest possible weight-loss number, retatrutide is very likely to deliver it once approved. Across five Phase 3 trials now, it has consistently outperformed approved GLP-1 options on percentage weight loss, even in harder-to-treat populations like TRIUMPH-2 and TRIUMPH-3's.

If you have established cardiovascular disease and are hoping retatrutide will specifically protect your heart, the honest answer, as of July 2026, is that nobody knows yet — including Lilly. TRIUMPH-3's MACE data is directionally mixed and statistically inconclusive in both directions. Wegovy has cardiovascular proof today. Retatrutide does not, and won't until TRIUMPH-Outcomes reports in 2029. This is a genuine decision point worth discussing with a cardiologist rather than a marketing headline.

If you have type 2 diabetes and are focused on glycemic control, TRIUMPH-2's -1.5 to -1.6 percentage point HbA1c reduction is solid and competitive with tirzepatide's SURPASS results, but it is not a clear step-change improvement over what's already available. The weight-loss advantage is real; the glycemic advantage is more modest.

Analyst Consensus and What Comes Next

Wall Street's reaction to the July 23 data was cautiously positive on efficacy and measured on the cardiovascular question. Andy Hsieh of William Blair called it "difficult to draw solid conclusions at this point" regarding the MACE data specifically (BioPharma Dive, July 23, 2026) — a fair summary of a trial that wasn't built to give a clean answer either way. RBC Capital's Trung Huynh, as noted above, framed the weight-loss numbers as meeting expectations given the harder-to-treat populations enrolled. Citi's analyst team took a more market-focused view, describing retatrutide's positioning in populations like TRIUMPH-3's as "a more niche market opportunity for Lilly" — a signal that Wall Street sees retatrutide's near-term commercial story as somewhat narrower than a blanket Wegovy or Zepbound replacement (Fierce Biotech, July 23, 2026).

On the regulatory timeline, nothing about the cardiovascular data changes the confirmed Q1 2027 BLA filing date. Lilly has said it's completing the manufacturing-focused Chemistry, Manufacturing, and Controls (CMC) data package before submitting, and that process — not the trial results — has been the gating factor. Standard FDA review from a Q1 2027 filing runs roughly 10–12 months, pointing to a realistic approval window of late 2027 to early 2028. For the full regulatory timeline, scenario analysis, and what could accelerate or delay it, see our companion piece on the retatrutide FDA approval date.

One open question the FDA will likely probe during review: how conservative should labeling language be regarding cardiovascular disease patients, given the directionally unfavorable MACE-3 signal? That's a labeling and marketing question, not necessarily an approval-blocking one — but it will shape how comfortable cardiologists are prescribing retatrutide to patients like those enrolled in TRIUMPH-3, at least until the dedicated cardiovascular outcomes trial reports.

For the broader status of every trial in the program — what's read out, what's still enrolling, and what feeds the BLA package — see our TRIUMPH trials status tracker. And for the complete picture of retatrutide's development, dosing, and comparisons, visit the retatrutide hub.

Frequently Asked Questions

What is retatrutide?

Retatrutide is Eli Lilly's investigational triple-agonist peptide, activating GLP-1, GIP, and glucagon receptors. It is not FDA-approved as of July 26, 2026, and remains in Phase 3 clinical development under the TRIUMPH trial program.

What did TRIUMPH-2 show?

TRIUMPH-2 enrolled 1,152 adults with type 2 diabetes and obesity or overweight. At 80 weeks, the 12 mg dose produced 20.8% weight loss and a 1.5 percentage point reduction in HbA1c, versus 0.2 points on placebo.

What did TRIUMPH-3 show?

TRIUMPH-3 enrolled 1,949 adults with severe obesity and established cardiovascular disease. At 80 weeks, the 12 mg dose produced 22.6% weight loss, plus reductions in triglycerides (-37.0%), non-HDL cholesterol (-16.5%), systolic blood pressure (-9.3 mmHg), waist circumference (-7.5 inches), and hsCRP (-51.2%).

Does retatrutide protect the heart?

That has not been established. TRIUMPH-3's broader MACE-5 composite favored retatrutide (hazard ratio 0.82) but wasn't statistically significant. The narrower MACE-3 endpoint (cardiovascular death, heart attack, stroke) was directionally worse for retatrutide (hazard ratio 1.12), also not statistically significant. The trial was not powered to answer this question definitively in either direction.

Why is 22.6% lower than the earlier 28.3% result?

TRIUMPH-3 enrolled patients with established cardiovascular disease and TRIUMPH-2 enrolled patients with type 2 diabetes — populations that consistently lose less weight on GLP-1 class drugs than the general obesity population TRIUMPH-1 enrolled. Analysts describe this gap as expected, not a red flag.

When will we know if retatrutide prevents heart attacks?

The dedicated cardiovascular outcomes trial, TRIUMPH-Outcomes (NCT06383390), is designed to answer this. Its primary completion date is February 2029 — roughly two years after retatrutide's most likely approval window of late 2027 to early 2028.

How does this compare to Wegovy's cardiovascular benefit?

Wegovy (semaglutide) already has an FDA-recognized cardiovascular benefit label based on the SELECT trial, which showed a statistically significant 20% reduction in major cardiovascular events (hazard ratio 0.80) in roughly 17,000 patients. Retatrutide has no equivalent proof yet.

When can I get retatrutide?

Retatrutide is not available by prescription as of July 2026. Eli Lilly plans to file its BLA with the FDA in Q1 2027, pointing to a realistic approval window of late 2027 to early 2028. See our retatrutide FDA approval date article for the full timeline.

Sources

1. Eli Lilly. "Lilly's Triple Agonist Retatrutide Successful in Two Additional Phase 3 Studies." Investor press release, July 23, 2026. https://investor.lilly.com/news-releases/news-release-details/lillys-triple-agonist-retatrutide-successful-two-additional
2. Reuters (Deena Beasley). "Lilly announces more next-gen obesity drug data, plans Q1 2027 FDA application." July 23, 2026. https://www.reuters.com/legal/litigation/lilly-announces-more-next-gen-obesity-drug-data-plans-q1-2027-fda-application-2026-07-23/
3. STAT News (Elaine Chen). "New data on Eli Lilly triple-G drug retatrutide leave open questions on heart benefit." July 23, 2026. https://www.statnews.com/2026/07/23/new-data-on-eli-lilly-triple-g-drug-retatrutide-leave-open-questions-on-heart-benefit/
4. Fierce Biotech. "Lilly's triple-G drug hits 22.6% weight loss; cardio risk impact disappoints." July 23, 2026. https://www.fiercebiotech.com/biotech/lillys-triple-g-drug-hits-226-weight-loss-cardio-risk-impact-disappoints
5. BioPharma Dive. "Lilly retatrutide FDA application obesity drug results." July 23, 2026. https://www.biopharmadive.com/news/lilly-retatrutide-fda-application-obesity-drug-results/825987/
6. Bloomberg. "Eli Lilly's next-generation weight-loss shot clears another hurdle." July 23, 2026. https://www.bloomberg.com/news/articles/2026-07-23/eli-lilly-s-next-generation-weight-loss-shot-clears-another-hurdle
7. Everyday Health. "Retatrutide weight loss heart disease diabetes trials." July 23, 2026. https://www.everydayhealth.com/diabetes/retatrutide-weight-loss-heart-disease-diabetes-trials/
8. ClinicalTrials.gov. TRIUMPH-Outcomes, NCT06383390. https://clinicaltrials.gov/study/NCT06383390
9. ClinicalTrials.gov. TRIUMPH-2, NCT05929079. https://clinicaltrials.gov/study/NCT05929079
10. ClinicalTrials.gov. TRIUMPH-3, NCT05882045. https://clinicaltrials.gov/study/NCT05882045