Weight-loss trials
8 trials · 15,462 people
Everyone asks the same question: how much weight do you lose? The trials answer it, and the answer is not the one in the advertising. People in the placebo group lose weight too — so the drug's real effect is the difference between the two bars, not the height of one.
- Treatment-8.7% to -24.2%placebo-2.1%
- n
- 338
- Weeks
- 48
- Treatment-15% to -20.9%placebo-3.1%
- n
- 2,539
- Weeks
- 72
The range is three separate dose arms, not an uncertainty interval.
[source] — SURMOUNT-1, NEJM 2022 - Treatment-20.4%placebo-3%
- n
- 3,417
- Weeks
- 68
This result is cagrilintide COMBINED with semaglutide. The monotherapy arm (302 participants) has no reported result.
[source] — REDEFINE 1, NEJM 2025 The comparator is semaglutide, not placebo — hence the small gap.
[source] — SURMOUNT-5, NEJM 2025In the trial's journal paper, 50.5% reached at least 15% weight loss, against 4.9% on placebo.
[source] — STEP 1, NEJM 2021- Treatment-6.2% to -14.9%placebo-2.8%
- n
- 386
- Weeks
- 46
Only 233 of 386 participants (60.4%) completed the treatment period.
[source] — Phase 2, Lancet D&E 2024 Reported in kilograms rather than as a share of body weight, so it cannot be set directly against the percentage figures.
[source] — SCALE, NEJM 2015- Treatment-19% to -28.3%placebo-2.2%
- n
- 2,339
- Weeks
- 80
Topline figures from a press release. Not published in a peer-reviewed journal, and therefore not the same kind of evidence as the published trials here.
[source] — TRIUMPH-1, Eli Lilly 2026
Both groups are drawn, because the drug's real effect is the gap between them — not the height of the whole bar. These are group averages from the cited trials and say nothing about what any one person would lose.