Key takeaways
- • Trial: STEP-4 (NCT03548987) — Phase 3, 803 participants over 68 weeks.
- • Drug studied: Wegovy (Semaglutide) — FDA-approved branded product.
- • Primary endpoint: Percent change in body weight from week 20 to week 68 after open-label run-in
- • Key result: Participants continuing semaglutide lost an additional 7.9%; those switched to placebo regained 6.9% (between-group difference -14.8 percentage points)
- • Published: JAMA, 2021.
Study design
STEP-4 was a phase 3 randomized controlled trial enrolling 803 participants over 68 weeks. The trial studied Wegovy (Semaglutide) for obesity / overweight and was published in JAMA in 2021.
Primary endpoint
Percent change in body weight from week 20 to week 68 after open-label run-in
Key results
| Measure | Value |
|---|---|
| Headline result | Participants continuing semaglutide lost an additional 7.9%; those switched to placebo regained 6.9% (between-group difference -14.8 percentage points) |
| Mean weight loss (highest dose arm) | 17.4% |
| Participants | 803 |
| Duration | 68 weeks |
| Phase | Phase 3 |
Citation
STEP-4. Published in JAMA, 2021.
GLP1Zoom did not conduct this trial. We summarize published primary literature. For verbatim methods and full results, consult the primary publication and the ClinicalTrials.gov registry record.
Related
- Wegovy drug page — pricing, FDA status, side effects, alternatives
- All semaglutide trials
- GLP-1 clinical trials database
Other Wegovy trials
- STEP-1 — Mean weight loss 14
- STEP-2 — Mean weight loss 9
- STEP-3 — Mean weight loss 16
- STEP-5 — Mean weight loss 15
- STEP-TEENS — Mean BMI change -16
Other Semaglutide trials
- SUSTAIN-1 (Ozempic) — HbA1c reduction 1
- SUSTAIN-6 (Ozempic) — 26% relative risk reduction in MACE on semaglutide vs placebo (HR 0
Important: This trial was conducted on the FDA-approved branded product Wegovy. Compounded versions of Semaglutide have NOT been studied in equivalent randomized controlled trials, and their efficacy and safety profile may differ.
GLP1Zoom is an affiliate-only comparator. We cite published trials; we do not conduct them. This page is informational and is not a substitute for personalized medical advice — always confirm any treatment decision with your prescribing clinician. Full disclaimer.