Beyond Weight Loss: 5 New Clinical Trial Uses for GLP-1 Drugs in 2026
Adrian Carter·Former metabolic disease researcher turned health writer. Breaks down how hormones like GLP-1 shape your weight, appetite, and energy — no jargon required.··9 min read
Beyond Weight Loss: 5 New Clinical Trial Uses for GLP-1 Drugs in 2026
GLP-1 receptor agonists were already reshaping medicine as obesity drugs. Now, phase 2 and phase 3 trials are showing they do something far more sweeping: protect the heart, kidneys, and liver — and potentially the brain — through mechanisms that appear to go well beyond dropping pounds. A 2025 meta-analysis of 85,373 participants across 11 randomized controlled trials found that GLP-1 receptor agonists reduce the composite kidney outcome by 18%, major adverse cardiovascular events by 13%, and all-cause mortality by 12%, with no increase in serious adverse events [8]. This is not a drug class built around a single trick anymore.
1. Cardiovascular Protection Without Requiring Diabetes
For years, cardiovascular outcome trials for GLP-1 drugs enrolled people with type 2 diabetes. The working assumption was that the cardiometabolic benefits flowed from better blood sugar control. The SELECT trial broke that assumption cleanly. Researchers enrolled 17,604 people who had established cardiovascular disease and were overweight or obese — but who did not have diabetes — and randomized them to semaglutide 2.4 mg weekly or placebo [2]. This was a deliberate choice: if the drug works for the heart only through glucose improvement, it should not have shown much in this population.
It showed plenty. Over a median of 39.8 months, semaglutide reduced the three-point major adverse cardiovascular events endpoint — a composite of nonfatal heart attack, nonfatal stroke, and cardiovascular death — from 8.0% in the placebo group to 6.5% in the semaglutide group. That translates to a 20% relative risk reduction, with a hazard ratio of 0.80 (95% CI 0.72–0.90; p<0.001) [2]. Participants on semaglutide also lost an average of 15.2% of body weight over the trial, but the cardiovascular benefit persisted across subgroups regardless of how much weight individuals lost — a finding that researchers are still working to fully explain.
The mechanistic picture is still being assembled, but several pathways beyond glucose regulation are under investigation. GLP-1 receptors are expressed directly on cardiomyocytes and vascular endothelial cells, and activation appears to reduce systemic inflammation, lower blood pressure, and improve endothelial function — all in ways that are partly independent of weight change. The SELECT data suggest these direct effects are real and clinically meaningful. For clinicians managing patients with obesity and cardiovascular history who do not have diabetes, this trial fundamentally changed the risk-benefit calculus for GLP-1 therapy.
This content is for informational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any supplement or making changes to your health regimen.
AC
Adrian Carter
Former metabolic disease researcher turned health writer. Breaks down how hormones like GLP-1 shape your weight, appetite, and energy — no jargon required.
Former metabolic disease researcher turned health writer. Breaks down how hormones like GLP-1 shape your weight, appetite, and energy — no jargon required.
GLP-1semaglutidetirzepatideclinical trials
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Clinical Trials
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2. Chronic Kidney Disease: Protecting the Filters
Chronic kidney disease (CKD) affects around 700 million people globally and remains one of the most underdiagnosed conditions in medicine. Standard therapies have included blood pressure management, RAAS blockade, and more recently SGLT2 inhibitors — but residual risk remains high. The FLOW trial, a phase 3 randomized controlled study, enrolled 3,533 people with type 2 diabetes and CKD across 28 countries and followed them for a median of 3.4 years [1]. The primary question was whether semaglutide 1.0 mg weekly could reduce hard kidney endpoints on top of standard care.
The answer was unambiguous. Semaglutide reduced the primary composite kidney endpoint — which included sustained 50% or greater decline in eGFR, kidney failure, cardiovascular death, and kidney-related death — by 24% compared with placebo, with a hazard ratio of 0.76 (95% CI 0.66–0.88; p=0.0003) [1]. That is a substantial absolute risk reduction over three-and-a-half years of follow-up. Cardiovascular mortality fell by 29%, and all-cause mortality by 20%, making this a trial that moved kidney specialists and cardiologists simultaneously. The eGFR slope — the rate at which kidney function declines over time — was also significantly slower in the semaglutide group, at -1.16 mL/min/1.73m² per year better than placebo (p<0.001) [1].
Why would a GLP-1 drug protect the kidneys? The most likely explanation is multifactorial. GLP-1 receptors are expressed in the kidney itself, particularly in the proximal tubule. Activation appears to reduce glomerular hyperfiltration, lower intraglomerular pressure, and decrease albuminuria — the protein leakage that signals kidney stress — through mechanisms that are at least partially weight-independent. Reduced inflammation and lower blood pressure also contribute. The FLOW result, combined with the meta-analysis showing an 18% reduction in composite kidney outcomes across 85,373 participants [8], makes a compelling case that kidney protection should now be considered a primary GLP-1 class effect.
3. Metabolic Liver Disease: Reversing Fatty Liver at the Biopsy Level
Metabolic dysfunction-associated steatohepatitis — MASH, formerly known as NASH — is a form of liver disease where excess fat accumulates and drives inflammation that can progress to cirrhosis and liver cancer. It affects an estimated 6–8% of the global population, and until recently, pharmacological options were essentially nonexistent. The ESSENCE trial changed that. This phase 3 randomized controlled trial enrolled 800 patients with biopsy-confirmed MASH and randomized them to semaglutide 2.4 mg weekly or placebo [3]. Liver biopsies at baseline and after 72 weeks were reviewed by independent pathologists — the gold standard for MASH research.
The trial results were striking by the standards of a field accustomed to modest improvements. MASH resolution without worsening of fibrosis occurred in 62.9% of participants on semaglutide versus 34.3% on placebo — a difference of 28.7 percentage points (p<0.001) [3]. That is not a small margin. Fibrosis stage improvement occurred in 36.8% of the semaglutide group versus 22.4% of the placebo group (p<0.001). Participants on semaglutide also lost an average of 10.5% of body weight compared with 2.0% on placebo, and the investigators found that the liver-specific improvements correlated with but were not fully explained by weight loss alone, suggesting direct hepatic effects of GLP-1 activation.
The mechanism in the liver involves multiple pathways. GLP-1 receptors in hepatic stellate cells and resident immune cells appear to directly suppress the inflammatory and fibrogenic signaling that drives MASH progression. Reduced de novo lipogenesis, improved insulin sensitivity at the liver level, and decreased oxidative stress all likely play roles. For patients with MASH — who previously had no approved pharmacological options beyond lifestyle change — a 62.9% histological resolution rate represents a meaningful clinical advance, particularly given the slow and variable trajectory of the disease.
4. Heart Failure with Preserved Ejection Fraction
Heart failure with preserved ejection fraction, or HFpEF, is the form of heart failure where the heart muscle contracts normally but the heart itself is too stiff to fill efficiently. It accounts for roughly half of all heart failure cases and has historically been particularly resistant to pharmacological treatment — the field had been frustrated by a string of neutral or negative trials for conditions that worked in the other form of heart failure (HFrEF). A large proportion of HFpEF patients have obesity, and the connection between adipose tissue, cardiac stiffness, and systemic inflammation has been a subject of intense investigation.
The STEP-HFpEF program enrolled patients with HFpEF (ejection fraction 45% or greater) and obesity in two separate randomized controlled trials that were then analyzed together in a prespecified pooled analysis published in The Lancet in 2024 [4]. Across 1,145 participants, semaglutide 2.4 mg weekly produced a 7.5-point greater improvement in the Kansas City Cardiomyopathy Questionnaire Clinical Summary Score — the primary patient-reported symptom outcome — compared with placebo (p<0.0001). That 7.5-point difference exceeds the threshold typically considered the minimum clinically meaningful change for the instrument. Hospitalizations for heart failure were reduced by 73% relative to placebo, with a hazard ratio of 0.27 (95% CI 0.12–0.56) [4]. Six-minute walk distance improved by 17.1 meters more in the semaglutide group. These are not marginal numbers.
The likely mechanisms overlap with those observed in other organs. Reducing visceral adiposity decreases the mechanical compression of the heart and reduces the systemic inflammatory load that contributes to myocardial stiffness. GLP-1 receptors in cardiac tissue may also play a direct role in reducing fibrosis and improving diastolic relaxation. What is notable about the STEP-HFpEF findings is that the symptom improvements were substantial even accounting for differences in weight loss between groups — pointing again to mechanisms beyond simple caloric reduction. For a condition that has resisted most pharmacological interventions, this pooled analysis represents the clearest positive signal in years.
5. Obstructive Sleep Apnea: More Than Weight Loss Working at Night
Obstructive sleep apnea (OSA) affects an estimated 1 billion people worldwide and is strongly associated with obesity, which narrows the upper airway both structurally and through changes in breathing control. The standard treatment remains continuous positive airway pressure (CPAP), but adherence is notoriously difficult, and a substantial portion of patients with obesity and OSA have residual disease even with optimal CPAP use. The SURMOUNT-OSA program enrolled people with moderate-to-severe OSA and obesity across two parallel phase 3 trials, randomizing them to tirzepatide — the dual GLP-1 and GIP receptor agonist — or placebo, with participants in one trial using CPAP and those in the other not using CPAP [5].
Tirzepatide reduced the apnea-hypopnea index — the count of breathing interruptions per hour of sleep, the primary measure of OSA severity — by 25.3 events per hour in the CPAP trial versus a 5.3 event reduction in the placebo group, a statistically significant difference of 20.0 events per hour (p<0.001) [5]. In the non-CPAP trial, the tirzepatide group reduced AHI by 29.3 events per hour versus 5.5 on placebo, a difference of 23.8 events per hour (p<0.001). Both trials reached their primary endpoints with the same magnitude of effect, which is unusual and reassuring. Based on these results, the FDA approved tirzepatide for OSA in December 2024, making it the first pharmacological treatment approved specifically for this indication in the United States.
The OSA result is interesting mechanistically because it raises a question: is the benefit entirely explained by weight loss, which physically opens the upper airway? The answer appears to be: not entirely. The reduction in AHI exceeded what would be predicted from weight loss alone in both trials, and researchers have proposed that GLP-1 and GIP receptor activation may influence the neural control of upper airway muscle tone during sleep. Some evidence also points to reduced fluid redistribution to the upper airway overnight with lower visceral fat burden. The full mechanism is still being investigated, but the clinical result is clear enough that tirzepatide is now an evidence-based option for patients with moderate-to-severe OSA who also carry excess weight.
Beyond the Top 5: What Emerging Trials Are Showing
The five indications above are supported by phase 3 randomized controlled trial data. Two additional areas are generating compelling phase 2 signals that are worth following closely, even if they require larger confirmatory trials before clinical practice should change.
Alcohol use disorder. A phase 2 randomized controlled trial published in JAMA Psychiatry in 2025 enrolled 48 adults with alcohol use disorder and randomized them to semaglutide 0.5 mg weekly or placebo for nine weeks [6]. The study was small and single-site, which appropriately limits confidence, but the signal was clear: semaglutide significantly reduced laboratory-measured alcohol consumption (regression coefficient -0.48; p=0.01), drinks per drinking day (-0.41; p=0.04), and craving scores (-0.39; p=0.01) [6]. The proposed mechanism involves GLP-1 receptor activity in the mesolimbic dopamine system — the brain's reward circuitry — where GLP-1 signaling appears to blunt the rewarding properties of alcohol. Larger multicenter phase 3 trials are now recruiting, and this area is being watched closely by addiction medicine researchers.
Alzheimer's disease. The ELAD trial, published in Nature Medicine in early 2026, tested liraglutide against placebo in 204 patients with mild-to-moderate Alzheimer's disease over 52 weeks [7]. The trial missed its pre-specified primary outcome, which was preservation of cerebral glucose metabolism measured by PET scan — a disappointing result in headline terms. However, several secondary outcomes were meaningfully positive: executive function significantly improved in the liraglutide group (p=0.01), and brain atrophy in memory and language regions was approximately 50% lower than in the placebo group [7]. The interpretation is genuinely uncertain — a trial that misses its primary endpoint is a trial that missed its primary endpoint — but the secondary findings in brain volume preservation are striking enough that a larger, better-powered trial seems warranted. The biological rationale is strong: GLP-1 receptors are expressed throughout the brain, GLP-1 signaling reduces neuroinflammation and amyloid burden in animal models, and the epidemiological link between insulin resistance and Alzheimer's risk has been recognized for years.
The diversity of indications now emerging from GLP-1 clinical trials reflects a growing understanding that these drugs are acting on a receptor system distributed throughout the body — not just the pancreas and the appetite centers of the hypothalamus. The class effect picture is becoming clearer with each new trial readout, and the meta-analysis anchoring all of it — 85,373 participants, 11 trials, 18% kidney benefit, 13% cardiovascular benefit, 12% mortality benefit [8] — suggests the story has further to run.
Frequently Asked Questions
Can GLP-1 drugs be prescribed specifically for chronic kidney disease or heart failure, even without diabetes?
Regulatory approvals vary by country and evolve rapidly. As of early 2026, the main approved indications remain type 2 diabetes management, obesity, and — for tirzepatide specifically — obstructive sleep apnea. The FLOW and STEP-HFpEF trial results are influencing clinical guidelines, and some specialist societies have issued position statements supporting GLP-1 use in CKD and HFpEF when obesity is present. Talk with a specialist in nephrology or cardiology about whether evidence-based off-label use is appropriate in your situation.
Does the cardiovascular benefit only apply to people with obesity and existing heart disease?
The SELECT trial specifically enrolled people with established cardiovascular disease who were overweight or obese but did not have diabetes [2]. The benefit in primary prevention — people who have not yet had a cardiovascular event — is being studied in ongoing trials but has not been definitively established in that group. The cardiovascular protection signal appears strongest in people who already have documented heart disease or multiple high-risk cardiovascular factors.
Are the liver benefits from GLP-1 drugs driven entirely by weight loss?
Based on the ESSENCE trial, probably not entirely. MASH resolution occurred in 62.9% of semaglutide-treated patients versus 34.3% on placebo [3], and the difference in liver outcomes was not fully accounted for by the 10.5% vs 2.0% weight loss difference between groups. Researchers have identified direct GLP-1 receptor activity in hepatic immune and stellate cells that appears to independently suppress liver inflammation and fibrosis. The weight loss contribution is real and meaningful, but direct hepatic effects likely add to the benefit.
What is the evidence quality behind these claims?
Five of the six primary studies reviewed here are phase 3 randomized controlled trials with large sample sizes and hard clinical endpoints — the gold standard for evidence in medicine [1, 2, 3, 4, 5]. The alcohol use disorder data comes from a phase 2 trial with only 48 participants, which appropriately means lower confidence [6]. The ELAD Alzheimer's trial is phase 2b and missed its primary outcome [7]. The cardiovascular and kidney findings are additionally supported by a high-quality L1 meta-analysis across 85,373 participants [8].
Will my doctor prescribe a GLP-1 drug for these new indications?
Clinical practice does not update as quickly as trial publications. The strongest current evidence for non-diabetes, non-obesity use is in cardiovascular protection, CKD, and HFpEF — areas where specialist societies are increasingly acknowledging the data. Whether a GLP-1 drug is appropriate for you depends on your complete clinical picture, other medications, insurance coverage, and your physician's judgment. Bringing published trial data to a consultation with your primary care doctor or relevant specialist is a reasonable starting point for the conversation.
References
[1] Perkovic V, et al. Effects of Semaglutide on Chronic Kidney Disease in Patients with Type 2 Diabetes. New England Journal of Medicine. 2024. DOI: 10.1056/NEJMoa2403347
[2] Lincoff AM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. New England Journal of Medicine. 2023. DOI: 10.1056/NEJMoa2307563
[3] Sanyal AJ, et al. Phase 3 Trial of Semaglutide in Metabolic Dysfunction-Associated Steatohepatitis. New England Journal of Medicine. 2025. DOI: 10.1056/NEJMoa2413258
[4] Butler J, et al. Semaglutide versus placebo in obesity-related HFpEF: pooled STEP-HFpEF analysis. The Lancet. 2024. DOI: 10.1016/S0140-6736(24)00469-0
[5] Malhotra A, et al. Tirzepatide for Obstructive Sleep Apnea and Obesity. New England Journal of Medicine. 2024. DOI: 10.1056/NEJMoa2404881
[6] Hendershot CS, et al. Once-Weekly Semaglutide in Adults With Alcohol Use Disorder. JAMA Psychiatry. 2025. DOI: 10.1001/jamapsychiatry.2024.4789
[7] Edison P, et al. Liraglutide in mild to moderate Alzheimer's disease: the ELAD trial. Nature Medicine. 2026. DOI: 10.1038/s41591-025-04106-7
[8] Badve SV, et al. Effects of GLP-1 receptor agonists on kidney and cardiovascular disease: meta-analysis. Lancet Diabetes & Endocrinology. 2025. DOI: 10.1016/S2213-8587(24)00271-7
This content is for informational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any supplement or making changes to your health regimen.
