Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity (STEP 4) — VialBase Research
high
- Continued semaglutide maintained 17.4% total weight loss at 68 weeks
- Switching to placebo resulted in regain of ~two-thirds of prior weight loss
- Demonstrates need for ongoing treatment to maintain benefits
Summary
STEP 4 used a unique withdrawal design to assess weight loss maintenance with continued semaglutide treatment. All participants received semaglutide 2.4 mg for 20 weeks (run-in), then were randomized to continue semaglutide or switch to placebo for 48 additional weeks. The trial demonstrated that discontinuation leads to significant weight regain.
Key Findings
- After 20-week run-in: mean weight loss of 10.6% in both groups
- Continued semaglutide group: additional 7.9% weight loss (total -17.4%) by week 68
- Switched-to-placebo group: regained 6.9% (net -5.0% from baseline) by week 68
- Cardiometabolic improvements (waist circumference, HbA1c, lipids) also reversed with discontinuation
- Treatment difference of -14.8 percentage points at week 68
- Regain began promptly after switching to placebo
Methodology
Randomized withdrawal study. 803 adults completed 20-week semaglutide run-in, then randomized 2:1 to continued semaglutide (n=535) or placebo (n=268) for 48 weeks. Lifestyle intervention throughout. Primary endpoint: percent change in body weight from randomization to week 68.
Limitations
- Withdrawal design means no true long-term placebo comparison from baseline
- Does not test gradual dose tapering strategies
- Weight regain may be partly behavioral (return to prior habits)
- Does not evaluate intermittent dosing strategies
- 20-week run-in may select for responders/tolerators
Relevance to Content
Perhaps the most important STEP trial for honest content creation. Demonstrates that semaglutide requires ongoing use to maintain benefits — critical for managing patient expectations. Content should present this alongside STEP 1/5 efficacy data to give a complete picture. Useful for articles addressing “what happens when you stop semaglutide.”
See Also
- Parent compound: Semaglutide