Evidence section
Semaglutide studies explained
Two pharmacists registered and practising in British Columbia read this page against the study pages and papers it lists and signed it. Their names are withheld from the site and held on file; their registration is confirmed on request.
Semaglutide is the medicine behind Wegovy and Ozempic. The STEP programme tested it for weight management, SELECT tested it for heart attack and stroke prevention, OASIS tested a tablet form, and ESSENCE tested it in liver disease. This hub lists every semaglutide study we have reviewed. Each page gives the numbers as the researchers reported them, says who was studied and for how long, and lists what the study cannot tell you. Studies are listed by year, not by result, and nothing here ranks one medicine against another.
Studies in this section (20)
Does semaglutide change fat and lean mass? The SUSTAIN 8 substudy
A SUSTAIN 8 substudy used DXA scans to compare fat and lean mass changes with semaglutide 1.0 mg and canagliflozin in diabetes. Canadian sites took part.
STEP 2: semaglutide for weight loss in adults with type 2 diabetes
STEP 2 tested weekly semaglutide 2.4 mg in 1210 adults with type 2 diabetes and a higher body weight. Plain-language results for Canadian readers.
STEP 3: semaglutide added to intensive behavioural therapy
STEP 3 added weekly semaglutide 2.4 mg to 30 counselling visits and a low-calorie diet in 611 US adults. Plain-language results for Canadian readers.
Semaglutide for NASH liver disease: the 2021 phase 2 trial
A 72-week phase 2 trial tested daily semaglutide in adults with NASH fatty liver disease. Plain-language summary for Canadian readers.
What the STEP 1 trial found about semaglutide and weight loss
STEP 1 tested weekly semaglutide 2.4 mg in 1961 adults without diabetes. A plain-language summary of the results for Canadian readers.
STEP 5: what two years of semaglutide did to body weight
STEP 5 followed adults on weekly semaglutide 2.4 mg or placebo for 104 weeks. Plain-language results for Canadian readers, including side effects.
STEP 8: weekly semaglutide versus daily liraglutide, head to head
STEP 8 directly compared weekly semaglutide 2.4 mg with daily liraglutide 3.0 mg over 68 weeks. Plain-language results for Canadian readers.
STEP TEENS: semaglutide in adolescents aged 12 to 17
STEP TEENS tested weekly semaglutide 2.4 mg in adolescents aged 12 to 17 with obesity over 68 weeks. Plain-language results for Canadian families.
Semaglutide and prediabetes: blood sugar results from STEP 1 and 3
In STEP 1 and STEP 3, most adults with prediabetes on semaglutide 2.4 mg had normal blood sugar at 68 weeks. What that means for Canadian readers.
OASIS 1: oral semaglutide 50 mg for weight loss over 68 weeks
OASIS 1 tested a once-daily 50 mg semaglutide tablet against placebo for 68 weeks in adults without diabetes. Plain-language results for Canadian readers.
SELECT: semaglutide and heart attack or stroke risk without diabetes
SELECT tested whether weekly semaglutide 2.4 mg lowered heart attacks, strokes and cardiovascular death in adults with heart disease. Canadian summary.
Semaglutide for NASH-related cirrhosis: 2023 phase 2 trial results
A small 48-week trial tested weekly semaglutide 2.4 mg in adults with NASH cirrhosis and found no clear benefit on liver scarring. Canadian summary.
SELECT: did semaglutide prevent diabetes in people with heart disease?
A planned SELECT analysis tracked blood sugar over three years on weekly semaglutide 2.4 mg in adults with heart disease and no diabetes. Canadian summary.
SELECT: semaglutide and kidney outcomes in adults without diabetes
A planned SELECT analysis looked at kidney outcomes with weekly semaglutide 2.4 mg in adults with heart disease and no diabetes. Canadian summary.
SELECT: semaglutide in people who already had heart failure
A planned SELECT analysis looked at weekly semaglutide 2.4 mg in 4,286 participants who had heart failure at the start. Canadian plain-language summary.
ESSENCE: semaglutide for MASH liver disease, 72-week interim results
ESSENCE tested weekly semaglutide 2.4 mg in adults with MASH fatty liver disease and moderate to advanced scarring. 72-week results for Canadian readers.
OASIS 2: oral semaglutide 50 mg in East Asian adults
OASIS 2 tested a daily 50 mg semaglutide tablet in 201 adults in Japan and South Korea, with and without type 2 diabetes. Summary for Canadian readers.
OASIS 4: oral semaglutide 25 mg for weight loss in adults
OASIS 4 tested a daily 25 mg semaglutide tablet against placebo in adults without diabetes. Weight results at 64 weeks, explained for Canadian readers.
SELECT safety analysis: semaglutide side effects in heart disease
A prespecified SELECT analysis reports serious adverse events, discontinuations and gallbladder problems with weekly semaglutide 2.4 mg. Canadian summary.
What a Cochrane review says about semaglutide for weight loss
A 2025 Cochrane review pooled 18 semaglutide trials with 27,949 adults. Plain-language summary of weight, side effect and heart results for Canada.
Other evidence sections
How to read these pages
Every page in this section explains one published study. The numbers are reported as the researchers published them, with a link to the paper on PubMed. Pages say what a study cannot tell you and never rank one medicine against another. They are education, not medical advice. For how a medicine is used and paid for in Canada, see medicines, public drug coverage by province and compare services.
Reviewed and signed by two pharmacists registered in British Columbia, 2026-09-18.