The short answer
Weekly semaglutide produced greater average weight loss than daily liraglutide in this direct trial. Both groups also received diet and activity counseling.
What was compared?
STEP 8 enrolled 338 adults with overweight or obesity without diabetes. The active groups received semaglutide 2.4 mg weekly or liraglutide 3.0 mg daily; 126 participants received semaglutide and 127 received liraglutide; additional participants received placebo. These are trial doses, not personal instructions.
At 68 weeks, average weight change was −15.8% with semaglutide, versus −6.4% with liraglutide.
Percentage of starting weight
Original chart based on the study. Values are reported group averages.
| Group | Average weight change |
|---|---|
| Semaglutide 2.4 mg | −15.8% |
| Liraglutide 3.0 mg | −6.4% |
The practical trade-off
Overall treatment discontinuation was 13.5% with semaglutide and 27.6% with liraglutide. These are all-cause discontinuations, not just side-effect withdrawals.
The treatment rules differed: semaglutide participants could use a lower maintenance dose, while participants unable to tolerate liraglutide's target dose stopped treatment and could restart escalation. That complicates a simple tolerability ranking. Participants also knew which active medicine they received.
The takeaway: This supports a difference between the regimens tested, not a universal winner for every person.
Sources
Rubino DM and colleagues, STEP 8, JAMA, 2022. Full paper. Funded by Novo Nordisk.