STEP-1 Explained: The 14.9% Semaglutide Weight-Loss Result
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STEP-1 was the pivotal semaglutide weight-management trial. Over 68 weeks, participants on semaglutide 2.4mg lost about 14.9% of body weight on average versus about 2.4% on placebo — the result behind Wegovy's approval.
- STEP-1 established semaglutide 2.4mg (Wegovy) for chronic weight management.
- Mean weight loss: ~14.9% over 68 weeks vs ~2.4% on placebo.
- Roughly a third of participants lost 20% or more of their body weight.
- Applies to FDA-approved semaglutide, not compounded formulations.
What STEP-1 measured
STEP-1 (Semaglutide Treatment Effect in People with Obesity) was the pivotal phase 3 trial that led to Wegovy's approval for chronic weight management. It enrolled nearly 2,000 adults with obesity, or overweight with a weight-related condition, and randomized them to weekly semaglutide 2.4 milligrams or placebo, both alongside lifestyle intervention.
The trial ran 68 weeks, long enough to capture the plateau where weight loss stabilizes. This duration matters: shorter trials can overstate ongoing loss by cutting off before the curve flattens.
The headline result
Participants on semaglutide lost about 14.9 percent of their body weight on average, compared with about 2.4 percent on placebo. For a 100-kilogram adult, that is roughly 15 kilograms of average loss attributable to the drug beyond lifestyle changes alone.
The distribution matters as much as the mean. Roughly a third of semaglutide participants lost 20 percent or more of their body weight, a degree of loss previously associated mainly with bariatric surgery. At the same time, a minority lost little, underscoring that response varies. The 14.9 percent figure is the population average, not a personal promise.
| Outcome | Semaglutide 2.4mg | Placebo |
|---|---|---|
| Mean weight loss | ~14.9% | ~2.4% |
| Lost ≥20% of weight | ~32% | ~2% |
| Duration | 68 weeks | 68 weeks |
| Applies to compounded? | No | — |
The limits of the number
Two caveats are essential. First, STEP-1 studied FDA-approved semaglutide at a specific dose and titration. Compounded semaglutide, oral semaglutide, and sublingual formulations were not studied here, and their results cannot be assumed to match. This is why applying the 14.9 percent figure to a compounded product is misleading.
Second, the weight loss depended on continued treatment plus lifestyle support. The STEP-1 extension data showed that stopping semaglutide led to substantial regain, which reframes the drug as a long-term therapy rather than a short course. The 14.9 percent is a with-treatment figure, not a permanent result.
| Trial | Focus |
|---|---|
| STEP-1 | Obesity, general population |
| STEP-2 | Type 2 diabetes |
| STEP-4 | Continued vs withdrawn treatment |
STEP-1 in context
STEP-1 sits within a larger programme. STEP-2 studied semaglutide in type 2 diabetes, STEP-3 added intensive behavioral therapy, and STEP-4 examined what happens on continued versus withdrawn treatment. Together they build a consistent picture: semaglutide produces substantial, durable weight loss while taken, with regain after stopping.
Compared with tirzepatide's SURMOUNT programme, semaglutide's average weight loss is strong but generally lower — the SURMOUNT-5 head-to-head confirmed this directly. STEP-1 remains the foundational semaglutide weight-loss evidence, and understanding exactly what it showed protects you from marketing that overstates or misattributes it.
Frequently asked questions
How much weight did people lose in STEP-1?
About 14.9% of body weight on average over 68 weeks on semaglutide 2.4mg, versus about 2.4% on placebo. Roughly a third lost 20% or more.
Does the 14.9% apply to compounded semaglutide?
No. STEP-1 studied FDA-approved semaglutide. Compounded formulations were not tested and their results cannot be assumed to match.
Do you regain weight after stopping?
STEP extension data showed substantial regain after stopping, which is why semaglutide is framed as a long-term therapy.
Sources
- Clinical trials via NEJM (STEP, SELECT, SURMOUNT, SURPASS).
- STEP-1 trial (Wilding et al., NEJM 2021).
- FDA — human drug compounding and GLP-1 status.
The numbers behind this page
The semaglutide price range, stated precisely
Standard-dose compounded semaglutide runs $49 to $279 a month across the 22 programmes we priced on October 15, 2026, with a median of $99. The spread is $230 a month, or $2,760 across a year, for a molecule that is chemically identical in every case.
The lowest standing month-to-month prices with no membership are Mondae at $87 and Eden at $99; lower stickers come with a sale, a prepaid year or a membership. Half the programmes sit below $99 and half above it, which makes the median a more useful reference point than the lowest sticker when judging a quote.
Two programmes printed a semaglutide microdose price on October 15, 2026 (Shed from $149, Noom Med $179); NexLife's microdose semaglutide has cost the same as its standard plan since November 8, 2026 ($109 a month month-to-month). Those figures are excluded from the range above. A microdose sits below every dose studied in the pivotal trials, so including it would compare two different things and would make the market look cheaper than it is at a therapeutic dose.
Three structural facts move a bill more than the headline rate. Whether the price is flat across covered doses or rises as you titrate. Whether a membership is billed separately from medication. And whether the advertised figure requires prepaying six or twelve months, which lowers the monthly number by transferring risk to you at exactly the point you are least certain you will continue.
What we do not claim in semaglutide
On October 15, 2026, compounded semaglutide ran $49 to $279 a month across the 22 programmes we priced.
We do not claim these prices will hold. Compounded pricing moves within weeks, and a figure without a capture date is not a fact. We do not claim a compounded preparation is equivalent to an approved product: it is not FDA-approved, is not therapeutically equivalent to any brand-name product, and FDA does not review it for safety, effectiveness or manufacturing quality before marketing.
And we do not claim to be a clinical resource. Which molecule suits you, at what dose, and whether treatment is appropriate at all are questions for a prescribing clinician who has your history. This is price research, and it is only useful once those questions are settled.
Reading the price against the market
What the plan term is worth
Standard-dose semaglutide spans $49 to $279 a month across the 22 programmes we priced on October 15, 2026, a spread of $230.
Several programmes publish two prices: the advertised rate, which requires a commitment, and the month-to-month rate, which does not. The gap between them is the price of flexibility, and it is rarely presented that way.
Compounded medication is generally not refundable once shipped, and most discontinuation happens in the first three months — precisely the window a twelve-month prepayment covers. Committing at signup and committing after reaching a dose you tolerate are materially different decisions, even though the advertised rate is identical.
We show month-to-month and prepaid figures side by side for that reason. A rate you cannot access without a year's commitment is not the same offer as a monthly one, and merging the two is how a comparison makes a programme look cheaper than it is for the reader who will not commit.
Questions this page answers
Does compounded semaglutide cost more at higher doses?
At the programmes listed here the monthly price is flat across covered doses; what changes the figure is the plan term, not the dose. Dose-tiered pricing does exist elsewhere in this market, so confirm at checkout.
Why is microdosed semaglutide cheaper?
Because it is less medicine. On October 15, 2026, Shed listed a semaglutide microdose from $149 a month and Noom Med at $179 after a $79 start. A microdose sits below every dose studied in the pivotal trials, so it is not a cheaper route to the result those trials measured.
What does compounded semaglutide cost per month in October 2026?
As of October 15, 2026, the 22 compounded semaglutide programs we could price on their own pages charge between $49 and $279 a month at their lowest all-in rate, with a median of $99, counting any required membership and the cheapest plan term each program prints. The low end is made of sale and "as low as" prices: WellMedr's fall sale and NextMeds both start at $49. Standing month-to-month rates with no membership start at $87 (Mondae) and $99 (Eden). Compounded semaglutide is not FDA-approved.
What does compounded semaglutide normally cost?
$49 to $279 a month at the lowest all-in rate across the 22 programs we priced on October 15, 2026, with a median of $99. Half the programs sit either side of that median, which makes it a better reference than the lowest sticker when you judge a quote.