Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP-1)
Wilding JPH, Batterham RL, Calanna S, et al. N Engl J Med. 2021;384(11):989–1002. View source ↗
The STEP-1 trial randomized 1,961 adults with body mass index ≥30 (or ≥27 with weight-related comorbidities and without diabetes) to once-weekly subcutaneous semaglutide 2.4 mg or placebo for 68 weeks, alongside lifestyle intervention. Mean change in body weight was -14.9% in the semaglutide arm versus -2.4% in placebo. Secondary endpoints — including weight reduction ≥5%, ≥10%, and ≥15% — favored semaglutide with high statistical significance. Adverse events were predominantly gastrointestinal and consistent with the known GLP-1 receptor agonist class profile.
Researchers ran a large 68-week study comparing weekly semaglutide injections to placebo in nearly 2,000 adults with overweight or obesity (without diabetes). On average, the semaglutide group lost about 15% of their starting body weight; the placebo group lost about 2%. The most common side effects were stomach-related (nausea, diarrhea), which is typical for this class of molecule.
