Wegovy has been one of the most studied weight loss medications in history, with multiple large-scale trials providing detailed data on what to expect. And with the approval of the higher 7.2mg dose in January 2026, the results have gotten even more impressive.
The clinical trial data
STEP 1 (the original pivotal trial): 1,961 adults with obesity, no diabetes. Over 68 weeks at the 2.4mg dose, participants lost an average of 14.9% of body weight, compared to 2.4% on placebo. 86% achieved at least 5% weight loss, and 69% achieved at least 10%.1
STEP UP (the higher dose trial): At the newer 7.2mg dose over 72 weeks, average weight loss was 20.7% — significantly more than the standard 2.4mg dose and close to Mounjaro's results. The UK was the first country to approve this dose in January 2026.2
For someone starting at 100kg, that translates to approximately 15kg lost at the 2.4mg dose or 21kg at the 7.2mg dose over about 18 months.
Two dose levels, two sets of expectations
This is important to understand when setting expectations. Most people currently prescribed Wegovy in the UK are on the 2.4mg maintenance dose, which produces ~15% weight loss. The 7.2mg dose produces ~20.7% but is newer and not yet universally available from all providers. Discuss with your prescriber which dose is appropriate and available for you.
The cardiovascular bonus
Beyond weight loss, the SELECT trial demonstrated that Wegovy 2.4mg reduces major cardiovascular events (heart attack, stroke, cardiovascular death) by 20% in people with obesity and established cardiovascular disease. This benefit was observed regardless of the amount of weight lost — suggesting semaglutide has cardiovascular protective effects beyond just reducing weight.3
What affects your results
The same factors that affect Mounjaro results apply here: starting weight, dose reached, diet and exercise, adherence, individual biology, and sex. Results are averages with wide individual variation. Some people lose 25%+; others may lose 8–10%. Both outcomes are consistent with the medication working — individual biology differs.
Real-world vs trial results
As with all medications, real-world weight loss tends to be somewhat lower than clinical trial averages. Trial participants receive structured support, regular monitoring, and consistent follow-up that isn't always replicated in private prescribing. Expect results in the range of 12–18% at the 2.4mg dose in real-world settings — still very significant.
The weight loss timeline
Wegovy's dose escalation is slower than Mounjaro's (the starting dose of 0.25mg is very low), so meaningful weight loss typically begins around weeks 9–12 as you reach the 1mg dose. The fastest weight loss usually occurs between months 4–10, with a gradual plateau thereafter. For a detailed month-by-month breakdown, see our GLP-1 weight loss timeline.