How large was the cardiovascular benefit in SELECT?

Semaglutide 2.4 mg reduced the composite of cardiovascular death, nonfatal MI, and nonfatal stroke by 20% (HR 0.80 to 95% CI 0.72, 0.90) compared to placebo over a median 39.8 months of follow-up in patients with obesity and established CVD.

Did SELECT include patients with type 2 diabetes?

No. Patients with diabetes or HbA1c at or above 6.5% were excluded. About 25% had prediabetes. SELECT specifically tested semaglutide in the non-diabetic obesity-plus-CVD population.

Is Wegovy now FDA-approved for cardiovascular risk reduction?

Yes. In March 2024, the FDA expanded the Wegovy label to include reduction of cardiovascular risk in adults with established CVD and overweight or obesity. This was the first cardiovascular indication for any anti-obesity medication.

What was the number needed to treat in SELECT?

Approximately 67 patients needed to be treated with semaglutide 2.4 mg for about 3 years to prevent one additional MACE event, compared to placebo plus standard of care.

Does SELECT mean semaglutide prevents heart attacks in everyone with obesity?

No. SELECT enrolled only patients with established atherosclerotic CVD (prior MI, stroke, or symptomatic PAD). It did not study primary prevention. Extending the findings to patients without existing heart disease goes beyond what the trial demonstrated.

How much weight did participants lose in SELECT?

The semaglutide group lost a mean of 9.4% body weight at week 104, versus 0.9% in the placebo group. Weight loss was sustained through the follow-up period, though some regain occurred in participants who discontinued treatment.

Was the cardiovascular benefit explained entirely by weight loss?

Likely not entirely. Pre-specified mediation analyses suggested that weight reduction accounted for only a portion of the benefit. Anti-inflammatory effects (as measured by CRP reductions) and possible direct vascular mechanisms may also contribute.

What were the main side effects in SELECT?

Gastrointestinal events (nausea, diarrhea, vomiting) were the most common. About 17% of semaglutide-assigned patients discontinued treatment versus 8% on placebo. Serious GI events were uncommon. There were small numerical increases in gallbladder-related events with semaglutide.

Do guidelines now recommend semaglutide for obesity with heart disease?

Yes. The AHA/ACC and other professional societies have incorporated SELECT's findings into updated guidance. Semaglutide 2.4 mg is now positioned alongside standard secondary prevention therapies for patients with obesity and established CVD.

Will insurance cover Wegovy for cardiovascular risk reduction?

Coverage is improving but inconsistent. The FDA cardiovascular indication strengthens prior authorization arguments. Individual plan formularies vary. Many patients still face significant out-of-pocket costs at current pricing of over $1,300 per month.

What SELECT Actually Changes in Clinical Practice

By HealthRX Medical Team

Published May 25, 2026Updated May 25, 2026Last reviewed May 25, 2026

At a glance

| Parameter | Detail | |---|---| | Trial name | SELECT (Semaglutide Effects on Cardiovascular Outcomes in People with Overweight or Obesity) | | N | 17,604 | | Intervention | Subcutaneous semaglutide 2.4 mg weekly | | Comparator | Placebo (both arms received standard of care) | | Duration | Median follow-up 39.8 months | | Primary endpoint | Time to first MACE (composite of CV death, nonfatal MI, nonfatal stroke) | | Key result | HR 0.80 (95% CI 0.72, 0.90; P <0.001), a 20% relative risk reduction |

Why This Trial Exists

Before SELECT reported, GLP-1 receptor agonists had proven cardiovascular benefits only in patients with type 2 diabetes. The SUSTAIN-6 and PIONEER 6 trials showed semaglutide reduced MACE in diabetic populations, but clinicians had no randomized evidence for the far larger group of patients carrying both obesity and cardiovascular disease without a diabetes diagnosis. SELECT was designed to close that gap. It enrolled adults aged 45 or older with a BMI of 27 or higher, confirmed atherosclerotic cardiovascular disease, and no history of diabetes.

The study was event-driven: it continued until at least 1,225 first MACE events accumulated. That target was reached at a median of 39.8 months, giving the trial statistical power well beyond what most cardiovascular outcome trials achieve.

Who Was Actually in the Trial

Understanding the enrolled population matters because it determines who the data apply to. The SELECT cohort had a mean age of 61.6 years. Mean BMI was 33.3 kg/m². Roughly 72% were male. Nearly all participants were on background statins (~90%), antihypertensives (~93%), and antiplatelet agents (~86%).

This is a heavily treated population. These patients were already receiving guideline-directed medical therapy for secondary cardiovascular prevention. Semaglutide produced its 20% MACE reduction on top of all of that, not instead of it.

Patients with HbA1c at or above 6.5% at screening were excluded. About 25% of participants had prediabetes (HbA1c 5.7 to 6.4%). The trial was intentionally designed to test the drug in a non-diabetic population, though the prediabetic subgroup still made up a meaningful share.

Methodology Notes Beyond the Abstract

A few design features deserve attention because they shape how to interpret the results.

Dose escalation. Participants started at 0.24 mg weekly and escalated over 16 weeks to the target 2.4 mg dose. This mirrors the FDA-approved Wegovy dosing schedule. In practice, some patients cannot tolerate the full dose. In SELECT, approximately 17% of semaglutide-assigned participants discontinued the drug, compared to about 8% on placebo. Most discontinuations were GI-related. The trial analyzed all events by intention-to-treat, meaning the 20% reduction includes those who stopped treatment early.

Standard of care allowed to evolve. Investigators could adjust background medications throughout the trial. If a patient's LDL climbed, the statin dose could be increased. This reflects real practice and means the trial tested semaglutide's additive benefit over dynamic, not static, medical therapy.

Adjudication. An independent clinical events committee, blinded to treatment assignment, adjudicated every MACE endpoint component. This is standard for major CV outcome trials but worth stating because the composite endpoint includes events (nonfatal MI, nonfatal stroke) that require clinical judgment to classify.

The Actual Results

Primary Endpoint

The primary composite MACE outcome occurred in 6.5% of semaglutide-treated patients versus 8.0% on placebo (HR 0.80 to 95% CI 0.72, 0.90, P <0.001). The Kaplan-Meier curves began separating around month 8 and continued to diverge through 48 months. That ongoing divergence matters: it suggests the benefit was not a one-time early effect that plateaued, but a persistent reduction in risk over time.

Individual MACE Components

| Component | Semaglutide | Placebo | HR (95% CI) | |---|---|---|---| | Cardiovascular death | 2.5% | 3.0% | 0.85 (0.71, 1.01) | | Nonfatal MI | 2.7% | 3.3% | 0.82 (0.68, 0.98) | | Nonfatal stroke | 1.7% | 2.2% | 0.79 (0.63, 0.99) |

Individually, nonfatal MI and nonfatal stroke reached significance. Cardiovascular death trended favorably but did not reach the P <0.05 threshold. This pattern is consistent with other GLP-1 RA trials in diabetes, where the composite drives the benefit more than any single component.

Weight and Metabolic Changes

Mean body weight dropped 9.4% in the semaglutide arm versus 0.9% with placebo at week 104. CRP fell significantly more in the semaglutide group. Waist circumference, HbA1c, and systolic blood pressure all improved, consistent with semaglutide's known metabolic effects. The open question is how much of the MACE reduction is mediated by weight loss itself versus direct anti-inflammatory or anti-atherosclerotic effects of GLP-1 receptor agonism.

A pre-specified mediation analysis from the SELECT investigators estimated that body weight reduction accounted for only a portion of the cardiovascular benefit, suggesting direct vascular and inflammatory mechanisms likely contribute.

What Changed in Practice After SELECT

FDA Label Expansion

In March 2024, the FDA expanded the Wegovy (semaglutide 2.4 mg) label to include reduction of cardiovascular risk in adults with established CVD and either obesity or overweight. This was the first anti-obesity medication to receive a cardiovascular indication. The practical effect: semaglutide moved from a "weight management" drug to a "cardiovascular risk reduction" drug, at least for this subgroup.

Guideline Updates

The AHA/ACC and the Obesity Medicine Association updated their clinical guidance to incorporate SELECT's findings. Semaglutide 2.4 mg is now positioned alongside statins, ACE inhibitors, and antiplatelets in the secondary prevention toolkit for patients with obesity and established atherosclerotic CVD. The 2023 AHA scientific sessions featured SELECT prominently, and subsequent expert consensus documents reference it as class-shifting evidence.

Insurance and Access Shifts

The cardiovascular indication changed the reimbursement conversation. Before SELECT, payers broadly classified GLP-1 RAs for obesity as cosmetic or lifestyle drugs and denied coverage. With a CV indication, clinicians can now submit prior authorizations citing cardiovascular risk reduction, not just BMI. Whether individual insurers have updated their formulary criteria varies widely, but the clinical argument for coverage is materially stronger.

Who the Data Apply To, and Who They Don't

SELECT enrolled patients with established CVD (prior MI, prior stroke, or symptomatic peripheral artery disease). The results are directly applicable to that population.

They are not directly applicable to:

Primary prevention patients. Someone with obesity and CV risk factors but no history of an event was not studied. Extrapolation is tempting but unproven.
Patients with type 2 diabetes. They were excluded. GLP-1 RA cardiovascular data in diabetes come from separate trials (SUSTAIN-6, LEADER, REWIND). SELECT addresses the non-diabetic gap specifically.
Patients with BMI 25, 26.9. The inclusion cutoff was BMI 27. The difference is small, but the data do not technically cover patients below that threshold.
Younger adults. The minimum age was 45. Whether younger patients with obesity and early CVD benefit equally is unknown.

These boundaries matter. A 38-year-old with a BMI of 31 and no cardiac history may benefit from semaglutide for weight management, but citing SELECT to justify it as a cardiovascular intervention would be a stretch of the evidence.

Limitations the Authors Acknowledged

The SELECT investigators were transparent about several limitations in the published report.

Discontinuation asymmetry. More patients stopped semaglutide than placebo. The ITT analysis captures this, but the on-treatment effect may be larger than the reported HR of 0.80. Conversely, some treatment-effect dilution occurred.

Homogeneous demographics. Over 70% of participants were male. Roughly 84% were White. The trial was international, but the population skews toward older White men. Generalization to women, younger patients, and non-White populations requires caution.

No mechanistic endpoint. SELECT was designed to test clinical outcomes, not mechanisms. It cannot answer whether the benefit comes from weight loss, CRP reduction, direct plaque stabilization, or all three. That question matters for understanding whether other weight loss interventions (bariatric surgery, other anti-obesity medications) would produce equivalent cardiovascular protection.

GI side effects and unblinding. Nausea and diarrhea were significantly more common with semaglutide. In principle, GI side effects could have functionally unblinded some participants. The blinded adjudication committee mitigates this concern for hard endpoints, but soft endpoint interpretation and participant behavior (e.g., seeking care for chest pain) could be influenced.

The Prescribing Question Clinicians Are Actually Asking

The practical question after SELECT is not whether semaglutide works for CV risk reduction. It does, in this population. The question is who should receive it now versus who should wait for additional data.

The strongest evidence supports initiating semaglutide 2.4 mg in patients who match the SELECT population: adults 45 or older, BMI 27 or above, established atherosclerotic CVD, no diabetes, already on guideline-directed medical therapy. For this group, the NNT over roughly 3 years is approximately 67 to prevent one MACE event.

For patients outside this profile, clinicians face a judgment call. A 55-year-old woman with obesity, hypertension, elevated CRP, and a strong family history of MI may seem like a reasonable candidate, but she was not in SELECT. Primary prevention data for semaglutide do not yet exist.

The cost remains a barrier. At current wholesale pricing, Wegovy runs over $1,300 per month. Even with improved insurance arguments, out-of-pocket costs limit access. The economic calculus changes if compounded semaglutide or biosimilar competition drives prices down, but as of mid-2026, cost remains the single largest obstacle to broad prescribing.

What Comes Next

Several ongoing studies will extend SELECT's implications. The SELECT extension data, examining outcomes beyond the primary analysis window, are expected to clarify whether benefits persist or attenuate with longer follow-up. Studies examining GLP-1 RA effects in heart failure with preserved ejection fraction (HFpEF), including the STEP-HFpEF program, address a related but distinct population. And the competitive field is active: tirzepatide cardiovascular outcome data (SURPASS-CVOT) will test whether dual GIP/GLP-1 agonism matches or exceeds semaglutide's CV benefit.

Frequently asked questions

›

References

Lincoff AM, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and cardiovascular outcomes in obesity without diabetes. N Engl J Med. 2023;389(24):2221-2232. PubMed
FDA. Wegovy (semaglutide) injection prescribing information. Revised March 2024. FDA Label
Kosiborod MN, Abildstrøm SZ, Borlaug BA, et al. Semaglutide in patients with heart failure with preserved ejection fraction and obesity. N Engl J Med. 2023;389(12):1069-1084. PubMed
Lingvay I, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and cardiovascular outcomes by baseline body-mass-index subgroup: SELECT trial. Lancet Diabetes Endocrinol. 2024. PubMed
Ryan DH, Lingvay I, Colhoun HM, et al. Semaglutide effects on cardiovascular outcomes in people with overweight or obesity (SELECT) rationale and design. Am Heart J. 2020;229:61-69. PubMed