Zepbound Surpasses Wegovy in Weight Loss: What the Latest Trial Reveals
New head-to-head study highlights Zepbound’s superior efficacy, but real-world considerations still matter
Clinical trial results: Zepbound outperforms Wegovy in weight loss
A landmark head-to-head clinical trial has demonstrated that Zepbound (tirzepatide) is more effective than Wegovy (semaglutide) in promoting weight loss among adults with obesity.
- The SURMOUNT-5 trial, involving 751 participants without diabetes but with at least one comorbid condition (e.g., high blood pressure or high cholesterol), found Zepbound led to an average 20.2% body weight reduction, compared to 13.7% with Wegovy.
- Participants taking Zepbound also experienced a greater reduction in waist circumference, with an average loss of 18.4 centimeters versus 13 centimeters in the Wegovy group.
These findings, published in The New England Journal of Medicine in May 2025, provide timely insight for patients and healthcare providers navigating a crowded weight loss medication landscape.
Understanding the trial’s design and real-world relevance
The SURMOUNT-5 trial included a broad demographic reflective of the general population, enhancing the study’s applicability.
- Participants were randomly assigned either Zepbound or Wegovy and monitored for 18 months.
- Notably, both drugs caused gastrointestinal side effects, but dropout rates were higher with Wegovy (5.6% versus 2.7%).
- However, only 80% of participants completed the trial, and because it was not blinded, potential bias may have influenced results.
Experts like Dr. Meera Shah from Mayo Clinic and Dr. Avlin Imaeda from Yale emphasize that despite limitations, the results support real-world outcomes, consistent with earlier data comparing Mounjaro (tirzepatide) and Ozempic (semaglutide).
Why Zepbound shows stronger results
One key factor is dosing.
- Zepbound was tested at higher doses (10–15 mg) than Wegovy (1.7–2.4 mg), which may have contributed to superior results.
- Novo Nordisk plans to present new data on higher-dose Wegovy (up to 7.2 mg) later in 2025, which could narrow the efficacy gap.
Additionally, mechanism of action plays a role.
- Both drugs are GLP-1 receptor agonists, aiding in appetite control, insulin regulation, and delayed gastric emptying.
- Zepbound also activates GIP (gastric inhibitory polypeptide) receptors, potentially enhancing blood sugar control and further stimulating weight loss.
Choosing between Zepbound and Wegovy: Factors beyond efficacy
Though Zepbound may appear to be the superior option, the best choice varies by individual circumstances.
Important considerations include:
- Insurance coverage: Many insurers are currently covering only semaglutide (Wegovy), prompting some patients to switch.
- Side effect profile: Some patients tolerate one medication better than the other.
- Secondary indications:
- Wegovy is FDA-approved for cardiovascular disease prevention, making it preferable for patients with a history of heart disease or stroke.
- Zepbound holds FDA approval for moderate-to-severe obstructive sleep apnea, broadening its therapeutic relevance.
As the number of Americans using GLP-1 medications surged by 700% between 2019 and 2023, and with 1 in 8 U.S. adults reporting usage, such distinctions become increasingly significant in clinical decision-making.
Final takeaways: A powerful tool, not a magic solution
Although Zepbound outperforms Wegovy in trials, both drugs offer substantial health benefits.
- Improved self-confidence, better mobility, enhanced sleep, and improved metabolic markers (like liver function and glucose control) are frequently reported by users.
- But experts caution: these medications must be paired with lifestyle changes, including a healthy diet and regular physical activity.
- Around 5% of patients may discontinue use due to side effects, making ongoing medical supervision essential.
As Dr. Shah puts it, “Patients often describe life-changing improvements, but these drugs aren’t standalone fixes—they’re part of a larger, sustainable health journey.”
