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Open calculatorFDA-approved trial data · 12 months
What the FDA-approved GLP-1 trials reported.
Drop in your weight and pick an FDA-approved product. The curves come from the STEP 1 (Wegovy®) and SURMOUNT-1 (Zepbound®) Phase 3 trials. Compounded preparations have not been studied in these trials and these results have not been clinically established for compounded medications.
Project your weight loss
Drag to your current weight and pick an approach.
Starting weight220lbs
120 lbs400 lbs
Trial average: 15% at 12 months
Where the numbers come from
Average total-body-weight loss from two landmark Phase 3 trials of FDA-approved products: STEP 1 followed 1,961 adults on semaglutide 2.4mg weekly for 68 weeks (mean loss 14.9%). SURMOUNT-1 followed 2,539 adults on tirzepatide 15mg weekly for 72 weeks (mean loss 20.9%). Both trials combined medication with modest lifestyle counseling. Lifestyle-only comparator arms lost about 3–5% in the same time.
The shape of the curve
Weight loss on GLP-1 medications is not linear. Most people lose the fastest in months 1–4 as appetite suppression and changes in food preference take effect, then the rate slows through months 5–9, and plateaus approaching month 12 as the body reaches a new metabolic set point. The model approximates this with an exponential decay toward a 12-month target, matching the published trial curves.
Important caveats
- These are trial averages of FDA-approved products. Compounded preparations have not been evaluated in these trials and results have not been clinically established for compounded medications.
- Most weight loss is regained within a year of stopping, per the STEP 4 extension trial. Treatment is typically long-term.
- Side effects (nausea, constipation) are most common in the first 4–8 weeks and typically resolve with dose titration.
- GLP-1 medications are not appropriate for everyone. A licensed provider reviews your health history before prescribing.
See if you qualify
Compounded semaglutide for $139 your first month, then $597 every 12 weeks ($199/mo average) — provider care included. Free shipping.
Start intakeProjection questions
In the STEP 1 trial of FDA-approved Wegovy® (semaglutide 2.4mg weekly, Novo Nordisk), adults lost an average of 14.9% of body weight at 68 weeks vs 2.4% on placebo — both groups received lifestyle counseling. For a 220 lb starting weight, that's roughly 33 lbs of total loss. Compounded preparations have not been studied in these trials and these results have not been clinically established for compounded medications.
In the SURMOUNT-1 trial of FDA-approved Zepbound® (tirzepatide 15mg weekly, Eli Lilly), adults lost an average of 20.9% of body weight at 72 weeks. Lower doses produced proportionally less loss: 15% at 5mg, 19.5% at 10mg. These results were observed with the FDA-approved product and have not been clinically established for compounded medications.
Most weight loss on GLP-1 medications happens in the first 4–6 months as appetite suppression and altered food preferences kick in. Loss then slows as the body adapts metabolically and individuals approach their new set point. This plateau shape is consistent across trials.
The STEP 4 extension trial showed that about two-thirds of weight lost is regained within a year of stopping semaglutide. GLP-1 medications are most effective as long-term treatments. Discuss duration and maintenance strategy with your provider.
These are trial averages of FDA-approved products. Individual results vary significantly based on starting weight, adherence, titration speed, diet quality, activity level, sleep, stress, and underlying metabolic factors. Use this as a rough planning tool — not a guarantee.
Pallas providers can prescribe compounded semaglutide (injection or oral tablet) and compounded tirzepatide injection when there is a documented patient-specific clinical-difference rationale under FDCA §503A(b)(1)(C). Pallas plans to offer FDA-approved Wegovy® and Zepbound® as well; the projection above is based on those FDA-approved products' trials and is illustrative only — it is not a prediction of outcomes for any specific patient or for compounded preparations.
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