A new study has found that adults with obesity and prediabetes who used tirzepatide were able to sustain significant weight loss for more than three years — far outperforming those who received a placebo.
The findings come from an extended analysis of the SURMOUNT-1 trial, which was shared at the American Diabetes Association Scientific Sessions by Dr. Jamy D. Ard of Wake Forest University.
Long-lasting results
In the original SURMOUNT-1 study, nearly everyone taking tirzepatide lost at least 5% of their body weight after about a year and a half. More than half of people on the highest 15 mg dose shed 20% or more. This new data shows that these impressive results didn’t just fade over time.
Researchers followed participants with both obesity and prediabetes out to 176 weeks (a little over 3 years). They found:
- Almost all (99%) of those on tirzepatide maintained at least a 5% weight loss, compared with 68% in the placebo group.
- Between 92% and 98% of people taking tirzepatide kept off at least 10% of their weight, versus 40% on placebo.
- Around 70% to 93% stayed down by at least 15%, compared to just 22% in the placebo group.
- Roughly half to 80% managed to maintain a weight loss of 20% or more, while only 7% on placebo did.
How long did people sustain weight loss?
The analysis also revealed that people on tirzepatide were able to keep the weight off for far longer than those on placebo:
- 5% weight loss: stayed off for about 167–168 weeks on tirzepatide, compared to 164 weeks on placebo.
- 10% weight loss: around 160–161 weeks on tirzepatide vs. 128 weeks on placebo.
- 15% weight loss: 141–153 weeks on tirzepatide vs. just 65 weeks on placebo.
- 20% weight loss: 129–140 weeks on tirzepatide vs. 65 weeks on placebo.
Who benefits most?
According to Dr. Ard, people tend to show their response to tirzepatide early on. “Those who eventually reach a 20% weight loss typically cross that threshold around 9 months,” he said.
The study highlighted that between 73% and 80% of people on the 10 mg and 15 mg doses could achieve at least a 20% drop in body weight.
This research reinforces the importance of continuing tirzepatide therapy to maintain long-term weight loss. “It really confirms what we see in practice: sustained treatment leads to sustained results,” Ard said.
