SURMOUNT-1 Trial: Key Findings Explained in Plain Language
Tirzepatide produced 22.5% average body weight loss over 72 weeks in people with obesity -- the largest weight reduction ever recorded in a Phase 3 trial of this size.
Study overview
Conducted by
Eli Lilly, principal investigator Dr. Ania Jastreboff (Yale)
Patients
2,539 adults with obesity (BMI 30+) or overweight (BMI 27+) with at least one weight-related condition
Duration
72 weeks
Published in
New England Journal of Medicine
Year
2022
Key findings
22.5% average body weight loss at the highest dose (15mg)
Participants on the 15mg dose lost an average of 52 lbs from a starting weight of ~231 lbs. The 10mg group lost 21.4% and the 5mg group lost 16.0%.
96% of participants lost at least 5% of their body weight
At the highest dose, nearly every participant achieved clinically meaningful weight loss. 63% lost at least 20% of body weight.
Placebo group lost 3.1%
Even with lifestyle counseling alone, the placebo group barely moved. This underscores that the drug, not the counseling, drove the results.
Improvements in metabolic markers across the board
Waist circumference decreased 19cm on average. Blood pressure, triglycerides, and fasting insulin all improved significantly.
What this means for you
SURMOUNT-1 established tirzepatide as the most effective obesity treatment in pharmaceutical history at the time of publication. For someone weighing 230 lbs, the average result was dropping to about 178 lbs over 72 weeks. These are results that previously required bariatric surgery.
Limitations
The trial ran for 72 weeks and did not study what happens after stopping the drug. Participants received lifestyle counseling alongside the drug, so results reflect the combination. The study population was predominantly white and female. Long-term safety data beyond 2 years is still accumulating.
See if this compound is right for your goals
Take a 2-minute quiz. Get a personalized protocol.