Semaglutide · 3 min read
STEP 1's 14.9%, STEP 5's two-year durability, the STEP 1 extension's regain lesson, and SELECT's 20% cardiovascular event reduction — the four results that define semaglutide in 2026.
STEP 1's 14.9%, STEP 5's two-year durability, the STEP 1 extension's regain lesson, and SELECT's 20% cardiovascular event reduction — the four results that define semaglutide in 2026.
Semaglutide's claim in 2026 is not "strongest weight loss" — tirzepatide took that head-to-head. Its claim is the deepest outcomes evidence in the class, built across the STEP program and the SELECT trial. Four results carry most of the weight.
NEJM, 2021: 1,961 adults with obesity or overweight plus comorbidity, no diabetes, semaglutide 2.4 mg versus placebo, 68 weeks. Average loss 14.9% versus 2.4%, with a third of treated participants losing 20% or more. It was the first pharmacological result in shouting distance of surgery and it created the category tirzepatide later escalated. STEP 2 replicated the pattern in type 2 diabetes at the class-typical discount (9.6%).
STEP 5 extended treatment to two years: 15.2% average loss, with the curve flat from roughly week 60 — the drug holds what it takes. The STEP 1 extension showed the other side: a year after stopping drug and support, participants had regained about two-thirds of lost weight. Together they are the cleanest statement of how this class works: it is a treatment that works while treating, not a course that ends — examined fully in stopping GLP-1s and weight regain.
NEJM, 2023: 17,604 adults with established cardiovascular disease and overweight or obesity, without diabetes, followed a median 3.3 years. Semaglutide 2.4 mg cut major adverse cardiovascular events — heart attack, stroke, cardiovascular death — by 20% (HR 0.80). This is the trial that moved the class from cosmetic-adjacent to cardiology, earned Wegovy its risk-reduction indication, and pressured insurers' exclusion logic. Kidney outcomes (FLOW, in diabetes) and other endpoint trials have since thickened the file. Tirzepatide's SURPASS-CVOT answered its own cardiovascular question in 2025 in diabetes against an active comparator; the non-diabetic primary-outcomes crown remains semaglutide's.
Three habits keep these results honest in a pricing context. Averages hide distributions — individual results range from dramatic to minimal. Trial numbers describe the FDA-approved product at full dose with trial support — a benchmark compounded and dose-capped programs borrow but did not generate (Noom's 0.6 mg cap is the standing example). And outcome evidence is indication-specific: SELECT's 20% belongs to its population, not to every buyer of every semaglutide product. The database marks which products those trial numbers actually describe.
STEP 1: 14.9% average at 68 weeks (vs 2.4% placebo) in people without diabetes; STEP 2: 9.6% with type 2 diabetes; STEP 5: 15.2% sustained at two years.
In 17,604 people with cardiovascular disease and overweight/obesity without diabetes, semaglutide 2.4 mg reduced major cardiovascular events by 20% over a median 3.3 years — the class's landmark non-diabetic outcomes result.
In the STEP 1 extension, participants regained roughly two-thirds of lost weight within a year of stopping treatment and support — the central fact of the maintenance conversation.