Efficacy and safety of tirzepatide in people with obesity

Study design: Phase 3 double-blind, randomized, controlled trial


  • Number of patients studied: 2539
  • Inclusion criteria: Adults with BMI of 30 or more, or 27 or more and at least one weight-related complication, excluding diabetes
  • Exclusion criteria: Presence of diabetes


  • Experimental group: Once-weekly, subcutaneous tirzepatide (5 mg, 10 mg, or 15 mg) for 72 weeks
  • Control group: Placebo for 72 weeks

Primary outcome: Percentage change in weight from baseline and a weight reduction of 5% or more

Safety outcomes or Adverse Events

Adverse events in 78.9% to 81.8% of participants treated with tirzepatide, compared to 72.0% in the placebo group; most common were gastrointestinal events (nausea, diarrhea, and constipation)


In this 72-week trial in participants with obesity, 5 mg, 10 mg, or 15 mg of tirzepatide once weekly provided substantial and sustained reductions in body weight.