GLP-1 Results: What to Expect at 1, 3, 6 and 12 Months
In SURMOUNT-1, people on tirzepatide 15 mg weekly lost 20.9% of their body weight on average over 72 weeks, against 3.1% on placebo.
- Average loss, top dose
- 20.9%
- On placebo
- 3.1%
- Trial length
- 72 weeks
- Trial
- SURMOUNT-1
Weight loss and half-life overview
A dose's half-life in days is the time needed to remove half of it from your body. This figure comes from section 12.3 in the FDA label for each medicine.
Percentage of body weight. Trials differ in doses and lengths, so compare each result with the placebo from that same trial, found on its own page.
GLP-1 results: the numbers first
For each GLP-1, the top dose shown comes from its main weight trial. Different trials enrolled different people.
| Trial | Dose group | Average weight lost | Placebo or comparison | Weeks | Who was in it |
|---|---|---|---|---|---|
| STEP 1 | Semaglutide 2.4 mg weekly | 14.9% | 2.4% | 68 | Adults with obesity or overweight, without diabetes |
| OASIS 4 | Wegovy pill 25 mg daily | 13.6% | 2.4% | 64 | Adults with obesity or overweight, without diabetes |
| SURMOUNT-1 | Tirzepatide 15 mg weekly | 20.9% | 3.1% | 72 | Adults with obesity or overweight, without diabetes |
| SURMOUNT-2 | Tirzepatide 15 mg weekly | 14.7% | 3.2% | 72 | Adults with obesity or overweight and no type 2 diabetes |
| SCALE Obesity and Prediabetes | Liraglutide 3.0 mg daily | 7.4% | 3% | 56 | Adults with obesity or overweight, plus type 2 diabetes |
| ATTAIN-1 | Foundayo 17.2 mg daily | 11.1% | 2.1% | 72 | Adults with obesity or overweight, without diabetes |
| ATTAIN-2 | Foundayo 17.2 mg daily | 9.6% | 2.5% | 72 | Adults with obesity or overweight and no type 2 diabetes |
| STEP 2 | Semaglutide 2.4 mg weekly | 9.6% | 3.4% | 68 | Adults with obesity or overweight and no type 2 diabetes |
References: STEP 1 (FDA label (DailyMed)), SURMOUNT-1 (FDA label (DailyMed)), SURMOUNT-2 (PubMed), SCALE Obesity and Prediabetes (FDA label (DailyMed)), ATTAIN-1 (FDA label (DailyMed)), STEP 2 (PubMed).
How to read the average in pounds
At three starting weights, we applied the trial average of 20.9%. This calculation uses arithmetic, not a prediction for any one person. Some people lose more, while others lose less.
| Starting weight | Average loss on tirzepatide 15 mg weekly | Average loss on placebo |
|---|---|---|
| 180 lb | about 38 lb | about 6 lb |
| 220 lb | about 46 lb | about 7 lb |
| 260 lb | about 54 lb | about 8 lb |
Sources: FDA label (DailyMed).
Week by week
- During the early weeks, stomach side effects appear most often while the dose remains low and continues to rise. After every increase in the dose, they often come back for a few days.
- Week 72: the SURMOUNT-1 trial ends here, and this point provides the average weight loss shown above.
Sources: health.clevelandclinic.org, FDA label (DailyMed).
What makes it stall and what helps
- Find out which dose step you are on. Lower doses produced less weight loss in every trial listed above.
- Over the last month, count how many doses you missed or took late.
- Track your food and drinks for a few days. As portions shrink, liquid calories and grazing build up.
- Talk with your prescriber about checking your thyroid or blood sugar. If your progress has stalled for months, ask about switching medicines.