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Semaglutide · Phase 3 · Completed

STEP 2

In STEP 2, a phase 3 trial of semaglutide in adults with BMI of at least 27 kg/m2 and HbA1c 7-10% (53-86 mmol/mol), diagnosed with type 2 diabetes at least 180 days before screening (n=1,210), mean body weight fell 9.6% on 2.4 mg over 68 weeks, against 3.4% on placebo (Davies M et al. Lancet 2021 (STEP 2)).

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Results

STEP 2: mean percent change in body weight by armSTEP 22.4 mg-9.6%Placebo-3.4%
Mean percent change in body weight by arm, as each source reports it. Bars from different trials are not a head-to-head comparison: populations, durations and estimands differ.

Side effects reported

The most frequently reported adverse events were gastrointestinal adverse events in 63.5% on 2.4 mg and 57.5% on 1.0 mg against 34.3% on placebo.

Event2.4 mg1.0 mgPlacebo
Gastrointestinal adverse events63.5%57.5%34.3%

Design

Trial design and sources

Compound
Semaglutide
Phase
3
Population
Adults with BMI of at least 27 kg/m2 and HbA1c 7-10% (53-86 mmol/mol), diagnosed with type 2 diabetes at least 180 days before screening
Participants randomised
1,210
Duration
68 weeks
Primary endpoint
Coprimary: percentage change in bodyweight and achievement of weight reduction of at least 5% at 68 weeks, semaglutide 2.4 mg versus placebo
Estimand
Not stated in the source read
Read out
2 March 2021

The abstract gives no body-weight figure for the 1.0 mg arm and does not name the estimand (intention to treat).

  • Davies M et al. Lancet 2021 (STEP 2) open · checked 23 September 2026
  • ClinicalTrials.gov NCT03552757 open · checked 23 September 2026
  • Registry: NCT03552757

Questions

STEP 2, answered

What did STEP 2 find?

In STEP 2, a phase 3 trial of semaglutide in adults with BMI of at least 27 kg/m2 and HbA1c 7-10% (53-86 mmol/mol), diagnosed with type 2 diabetes at least 180 days before screening (n=1,210), mean body weight fell 9.6% on 2.4 mg over 68 weeks, against 3.4% on placebo (Davies M et al. Lancet 2021 (STEP 2)).

What side effects were reported in STEP 2?

The most frequently reported adverse events were gastrointestinal adverse events in 63.5% on 2.4 mg and 57.5% on 1.0 mg against 34.3% on placebo.