Semaglutide[Wegovy; Ozempic; Rybelsus]
Compound snapshot
Class
Long-acting GLP-1 receptor agonist
FDA approved
Yes — product-specific indications include chronic weight management, type 2 diabetes and cardiovascular-risk reduction in eligible adults
Clinical development
Approved
Last reviewed
September 2026
Research areas
Body weight / Type 2 diabetes / Cardiovascular outcomes / Appetite regulation
Regulatory status
FDA-approved prescription medicine — indication depends on product
Internet attention
Very high
Registry query
semaglutide
A long-acting GLP-1 receptor agonist. Wegovy is approved for chronic weight management and cardiovascular-risk reduction in specific adults; Ozempic and Rybelsus have separate type 2 diabetes indications. Products and approved uses are not interchangeable.
Reality check — what we actually know
Supported by human evidence
- STEP 1: mean weight change was −14.9% at 68 weeks versus −2.4% with placebo in adults without diabetes.
- SELECT: major cardiovascular events occurred in 6.5% with semaglutide versus 8.0% with placebo in adults with established cardiovascular disease and overweight or obesity without diabetes.
- SURMOUNT-5 directly compared the medicines: −13.7% mean weight change with semaglutide versus −20.2% with tirzepatide at 72 weeks.
Animal research only
- Rodent pharmacology informed development, but approved uses are supported by human randomised trials.
Mechanistically plausible
- GLP-1 receptor activation reduces appetite, slows gastric emptying and supports glucose-dependent insulin secretion.
Common internet claims
- "Everyone loses the trial average" — individual response varies widely.
- "Stopping is easy once goal weight is reached" — regain is common after withdrawal.
Not established
- That one GLP-1 medicine is best for every person
- Safety or equivalence of unapproved compounded or research-market products
- A universal self-directed stopping or tapering method
Evidence distribution
Each band is a live PubMed search for Semaglutide, filtered to that kind of study. Top is the strongest evidence; the base is reasoning, not proof. A band with no records means that kind of study has not been published for this compound yet.
Mechanism and reported findings
Mimics GLP-1 signalling: it increases glucose-dependent insulin release, reduces glucagon when glucose is elevated, slows stomach emptying and acts on appetite-regulating brain pathways. This can reduce hunger and food intake while improving glucose control.
- STEP 1 (NEJM, 2021): mean body-weight change was −14.9% at 68 weeks versus −2.4% with placebo in adults with overweight or obesity without diabetes
- SELECT (NEJM, 2023): major cardiovascular events occurred in 6.5% with semaglutide versus 8.0% with placebo in adults with established cardiovascular disease and overweight or obesity without diabetes
- SURMOUNT-5 (NEJM, 2025): mean weight change was −13.7% at 72 weeks with semaglutide versus −20.2% with tirzepatide in the direct open-label comparison
- The evidence base includes large randomised trials, cardiovascular outcomes data and regulatory review
Strength of the evidence: Established human efficacy for its labelled indications, supported by large randomised controlled trials and FDA review. Results are indication-, product- and population-specific; trial averages do not predict an individual's result.
Safety and known cautions
Prescription-only. Nausea, diarrhoea, vomiting and constipation are common. The US label includes a boxed warning about thyroid C-cell tumours seen in rodents and contraindicates use with a personal or family history of medullary thyroid carcinoma or MEN2; it also warns about pancreatitis, gallbladder disease, kidney injury from dehydration and aspiration risk. Weight regain is common after treatment stops. Use only with the prescribing clinician.
Evidence at a glance
No single score, on purpose. The line beside each bar shows how much reported outcomes vary between studies.
Development stage
- Discovery
- Preclinical
- Phase 1
- Phase 2
- Phase 3
- Regulatory review
- ApprovedCurrent