SURMOUNT Trial Overview: What the Zepbound Studies Show, Explained for Rochester Patients
When patients ask how well Zepbound works, the answer comes from a series of studies called the SURMOUNT trials. These large clinical trials tested tirzepatide, the active ingredient in Zepbound, in thousands of adults with obesity. Together, they shaped how physicians use the medication today. This SURMOUNT trial overview explains what each study tested and found. It also covers what the results mean for Rochester patients.
At Vital Health Medical Care in Pittsford, Dr. Sanin Syed, MD, uses this evidence to set realistic expectations with patients. She is dual board-certified in obesity medicine and internal medicine, with more than 20 years in medicine. Understanding the trials can help you know what to expect, and what questions to ask, before starting treatment.
Quick Answer: What Did the SURMOUNT Trials Show?
The SURMOUNT trials showed that tirzepatide produces substantial, sustained weight loss in adults with obesity. In SURMOUNT-1, the highest dose produced about 21% average weight loss over 72 weeks. Other trials showed strong results in people with type 2 diabetes, after lifestyle programs, and compared with semaglutide. They also showed that stopping treatment usually leads to weight regain.
- Main result: about 21% average weight loss at 72 weeks on the highest dose
- Type 2 diabetes: about 15% average weight loss, which is typically lower in people with diabetes
- Versus semaglutide: about 20% versus 14% in the head-to-head SURMOUNT-5 trial
- Stopping treatment: most people regained a substantial share of lost weight within a year
- Sleep apnea: results led to FDA approval for obstructive sleep apnea with obesity
SURMOUNT Trial Overview: Key Results at a Glance
The table below summarizes the main SURMOUNT trials. Each study used different participants and designs, so the numbers are best compared within each trial rather than across them.
|
Trial |
Who was studied |
Main finding |
| SURMOUNT-1 | About 2,500 adults with obesity or overweight, without diabetes | About 21% average weight loss at 72 weeks on 15 mg, vs about 3% on placebo |
| SURMOUNT-2 | Adults with obesity and type 2 diabetes | About 15% average weight loss at 72 weeks on 15 mg, vs about 3% on placebo |
| SURMOUNT-3 | Adults who first completed an intensive lifestyle program | About 18% additional weight loss after the program, while placebo regained weight |
| SURMOUNT-4 | Adults who lost weight on tirzepatide, then continued or stopped | Continuing: about 25% total loss; stopping: much of the loss regained |
| SURMOUNT-5 | Adults with obesity, tirzepatide vs semaglutide | About 20% vs 14% average weight loss at 72 weeks |
| SURMOUNT-OSA | Adults with obesity and obstructive sleep apnea | Large reductions in breathing interruptions during sleep |
What Are the SURMOUNT Trials?
SURMOUNT is the name of Eli Lilly’s phase 3 trial program for tirzepatide in weight management. Tirzepatide activates two hormone receptors, GLP-1 and GIP, which together reduce appetite and increase fullness. A separate program, called SURPASS, studied tirzepatide in type 2 diabetes and led to its approval as Mounjaro.
The SURMOUNT results led to Zepbound’s FDA approval for chronic weight management in 2023. Later, the SURMOUNT-OSA trials led to its approval for obstructive sleep apnea in adults with obesity.
A Quick Note on How Results Are Reported
Many trial results are reported in two ways. One method includes everyone who started the study, even those who stopped treatment. The other focuses on people who stayed on the medication as intended. The second method usually shows larger weight loss. This guide uses the more conservative numbers where possible, so you have realistic expectations.
SURMOUNT-1: The Foundation Trial
SURMOUNT-1 was the first and largest study in the program. It enrolled about 2,500 adults with obesity, or with overweight and a weight-related condition, who did not have diabetes. Participants took tirzepatide at 5 mg, 10 mg, or 15 mg weekly, or placebo, for 72 weeks. Everyone also received lifestyle counseling.
On the 15 mg dose, participants lost about 20.9% of their body weight on average. By comparison, the placebo group lost about 3.1%. Even the lowest dose, 5 mg, produced about 15% average weight loss. Results were published in the New England Journal of Medicine in 2022.
Three-Year Results in Prediabetes
Participants with prediabetes continued in SURMOUNT-1 for about three years, or 176 weeks. Over that time, tirzepatide reduced the risk of developing type 2 diabetes by about 94% compared with placebo. Weight loss was also largely maintained while people stayed on treatment. In addition, most tirzepatide participants returned to normal blood sugar levels.
Body Composition Findings
A substudy in SURMOUNT-1 used body composition scans to measure fat and lean mass. Most of the weight lost came from fat. Lean mass made up roughly one-quarter of total weight lost. That share is similar to other forms of weight loss. Lean mass includes water and organs as well as muscle, so true muscle loss is likely smaller.
SURMOUNT-2: People With Type 2 Diabetes
SURMOUNT-2 studied adults with obesity and type 2 diabetes for 72 weeks. On the 15 mg dose, participants lost about 14.7% of their body weight on average. On placebo, they lost about 3.2%. Blood sugar levels also improved substantially.
The smaller weight loss is typical. Across many weight loss medications, people with type 2 diabetes tend to lose somewhat less weight than people without diabetes. Even so, the results are meaningful for both weight and blood sugar control.
SURMOUNT-3: Medication After a Lifestyle Program
SURMOUNT-3 asked a practical question: what happens when people add tirzepatide after an intensive lifestyle program? First, participants completed 12 weeks of intensive diet and exercise support, losing about 6.9% on average. Then, those who lost enough weight were randomized to tirzepatide or placebo for 72 weeks.
The tirzepatide group lost an additional 18% or more of their body weight. Meanwhile, the placebo group regained part of what it had lost. In other words, medication built on lifestyle success rather than replacing it.
SURMOUNT-4: What Happens When You Stop
SURMOUNT-4 is especially important for patients. All participants took tirzepatide for 36 weeks first, losing about 21% of their body weight on average. Then, half continued tirzepatide and half switched to placebo for another 52 weeks.
Those who continued lost an additional 5.5%, reaching about 25.3% total weight loss. By contrast, those who stopped regained about 14% of their body weight, ending about 9.9% below where they started. A later analysis found that most people who stopped regained at least a quarter of lost weight within a year. Many of their health improvements, such as better blood pressure and cholesterol, also reversed.
The lesson is clear. Obesity behaves like a chronic condition, and many people need ongoing treatment to maintain results.
SURMOUNT-5: Tirzepatide Versus Semaglutide
SURMOUNT-5 compared tirzepatide directly with semaglutide, the active ingredient in Wegovy. Adults with obesity took either medication at its maximum tolerated dose for 72 weeks. Tirzepatide produced about 20.2% average weight loss, compared with about 13.7% for semaglutide. Tirzepatide also produced a larger average reduction in waist size.
However, these results compared tirzepatide with the standard 2.4 mg Wegovy dose. The newer Wegovy HD dose was not tested in this trial.
SURMOUNT-OSA: Sleep Apnea
The SURMOUNT-OSA trials studied adults with obesity and moderate to severe obstructive sleep apnea. Tirzepatide substantially reduced the number of breathing interruptions during sleep compared with placebo. Some participants improved enough that their sleep apnea was no longer considered moderate or severe. Based on these results, the FDA approved Zepbound for obstructive sleep apnea in adults with obesity in December 2024.
What the SURMOUNT Trials Mean for You
Overall, the trials offer several practical lessons. First, tirzepatide can produce substantial weight loss for many people, but individual results vary widely. Second, people with type 2 diabetes may lose somewhat less weight. Third, combining medication with nutrition and activity produced the strongest results. Finally, stopping treatment usually leads to regain, so long-term planning matters from the start. Your physician can help translate these averages into realistic goals for your own health and situation.
It is also important to remember the limits of clinical trials. Participants received regular visits, counseling, and close monitoring, which may not match every real-world setting. The trials were also funded by Eli Lilly, as is typical for drug approval studies. Still, the results have been published in major peer-reviewed journals and are consistent across studies.
What Comes Next
Research on tirzepatide continues. For example, SURMOUNT-MMO is studying whether tirzepatide reduces heart attacks, strokes, and other serious events in people with obesity. Its results are expected in the coming years. Other studies are exploring tirzepatide in heart failure, kidney disease, and other conditions linked to excess weight.
What We See in Practice
Many patients come in having read headlines about 20% weight loss. In our experience, sharing the full SURMOUNT picture helps set healthier expectations. Some patients lose more than the average, while others lose less. Patients often appreciate learning about SURMOUNT-4, because it explains why a long-term plan matters. That knowledge helps them stay engaged when progress slows.
How Vital Health Medical Care Uses This Evidence
At Vital Health Medical Care, treatment decisions are grounded in published evidence like the SURMOUNT trials. Every plan starts with a comprehensive consultation and a body composition scan. Dr. Syed then discusses whether Zepbound or another option fits your health, goals, and coverage.
Your plan also includes nutrition counseling, culinary medicine, exercise planning, and behavioral coaching. Regular follow-up visits track your progress against realistic expectations. Patients come from across the Rochester area, including Brighton, Penfield, Fairport, Webster, and Henrietta, and no referral is required.
Frequently Asked Questions
What is the SURMOUNT trial?
SURMOUNT is Eli Lilly’s phase 3 clinical trial program for tirzepatide, the active ingredient in Zepbound, in weight management. It includes several large studies in different groups of adults with obesity. The results led to Zepbound’s FDA approval.
How much weight did people lose in SURMOUNT-1?
On the highest 15 mg dose, participants lost about 20.9% of their body weight on average over 72 weeks. The placebo group lost about 3.1%. Results varied widely between individuals.
What happens if you stop Zepbound, according to SURMOUNT-4?
In SURMOUNT-4, people who stopped tirzepatide regained about 14% of their body weight over the next year. Those who continued lost an additional 5.5%. Many health improvements also reversed after stopping.
Is Zepbound better than Wegovy, according to SURMOUNT-5?
According to SURMOUNT-5, tirzepatide produced about 20.2% average weight loss, compared with about 13.7% for semaglutide at 72 weeks. However, the trial used the standard Wegovy dose, not the newer Wegovy HD. Individual results vary.
Does Zepbound prevent type 2 diabetes?
For people with prediabetes, the three-year SURMOUNT-1 study showed about a 94% lower risk of type 2 diabetes versus placebo. These benefits were seen while participants stayed on treatment.
Do people with diabetes lose as much weight on Zepbound?
Usually somewhat less. In SURMOUNT-2, people with type 2 diabetes lost about 14.7% on average on the highest dose. That pattern is common across weight loss medications.
Is Zepbound approved for sleep apnea?
Yes. Based on the SURMOUNT-OSA trials, the FDA approved Zepbound for moderate to severe sleep apnea with obesity in December 2024.
Do I need a referral to see a weight loss doctor in Rochester?
No referral is needed at Vital Health Medical Care. You can call 585-662-5786 to schedule a consultation directly. The team will also help verify your insurance benefits before treatment begins.
Strong Evidence, Realistic Expectations
The SURMOUNT trials provide some of the strongest evidence available for any weight loss medication. They show substantial results, important differences between groups, and the value of long-term treatment. This SURMOUNT trial overview can help you approach Zepbound with clear, realistic expectations. With the right plan and support, that evidence can translate into meaningful progress for you.
If you want to know whether Zepbound fits your health and goals, Dr. Sanin Syed and her team at Vital Health Medical Care can help.
Meet Dr. Sanin Syed – Leading Medical Weight Loss Specialist in Rochester, NY
Dr. Sanin Syed, founder and CEO of Vital Health Medical Care, is a board-certified obesity and internal medicine specialist. With over two decades of experience, Dr. Syed is dedicated to helping her patients achieve lasting weight loss and a healthier lifestyle.
- Recognized Expertise: Dr. Syed’s knowledge has been featured on NPR’s Evan Dawson Show and in the Rochester Academy of Medicine.
- Commitment to Patient Health: She focuses on building sustainable health habits and lifestyle changes that support long-term success.
Our clinic, located at 10 Office Parkway, Suite 100, Pittsford, NY, provides a welcoming and professional setting for patients who are ready to make positive changes.
Why Choose Vital Health Medical Care?
Experienced Weight Loss Doctor
Dr. Sanin Syed is one of the leading weight loss doctors in New York, with over 20 years of experience in medicine and obesity management. She holds dual board certifications from the American Board of Obesity Medicine and the American Board of Internal Medicine, ensuring you receive the highest standard of care.
Personalized Care
At Vital Health Medical Care, we believe in a personalized approach to weight loss. Our programs are tailored to meet your unique needs, ensuring you receive the best possible care and support on your weight loss journey.
Comprehensive Support
We provide ongoing support throughout your weight loss journey, including regular monitoring and adjustments to your plan as needed. Our comprehensive approach ensures you have the resources and guidance necessary to achieve your weight loss goals.
Insurance Acceptance
We understand that managing healthcare costs is important. That’s why we accept a wide range of insurance plans to make our weight loss treatments accessible and affordable for everyone.
Nutritional Counseling
Our qualified nutritionists create personalized diet plans that fit your lifestyle and dietary preferences. We provide expert guidance on making healthy food choices that support your weight loss goals.
Physician Consultation
Our experienced physicians, led by Dr. Syed, will work with you to find the best medication and treatment plan for your needs. We utilize FDA-approved medications such as Wegovy and Zepbound to support your weight loss efforts.
Health Coaching
Our health coaches provide ongoing support and motivation, helping you stay on track with your weight loss goals. They offer practical advice and encouragement to help you overcome challenges and achieve lasting success.
Culinary Medicine
Learn how to prepare healthy, delicious meals that support your weight loss journey with guidance from our culinary medicine experts. We offer cooking classes and workshops to help you develop the skills needed to maintain a healthy diet.
Meal Replacement
We offer meal replacement options that are nutritious and convenient, helping you manage your calorie intake effectively. Our meal replacements are designed to support your weight loss goals while ensuring you receive essential nutrients.
Individualized Exercise Plan
Our fitness experts develop personalized exercise plans tailored to your fitness level and goals. We provide guidance on the best types of exercise for weight loss and overall health, ensuring you achieve optimal results.
Comprehensive Weight Loss Treatment in Rochester, New York
Vital Health Medical Care offers evidence-based weight loss treatments designed to help you succeed. We take a holistic approach, integrating medication, diet, exercise, and behavioral changes to ensure long-term success. Contact us today to schedule a consultation and start your journey.