18+ · Research Use Only · Not for Human Consumption

Retatrutide · Phase 2 · Completed

Retatrutide phase 2 (Jastreboff)

In Retatrutide phase 2 (Jastreboff), a phase 2 trial of retatrutide in adults with a BMI of 30 or more, or 27 to under 30 with at least one weight-related condition (n=338), mean body weight fell 8.7% on 1 mg, 17.1% on 4 mg (pooled), 22.8% on 8 mg (pooled) and 24.2% on 12 mg over 48 weeks, against 2.1% on placebo (Jastreboff AM et al. N Engl J Med 2023;389:514-526).

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Results

Retatrutide phase 2 (Jastreboff): mean percent change in body weight by armRetatrutide phase 2 (Jastreboff)1 mg-8.7%4 mg (pooled)-17.1%8 mg (pooled)-22.8%12 mg-24.2%Placebo-2.1%
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

Retatrutide phase 2 (Jastreboff): The abstract reports gastrointestinal events as the most common, dose-related and mostly mild to moderate, without rates; rates by arm are in the full text, not read here.

Design

Trial design and sources

Compound
Retatrutide
Phase
2
Population
Adults with a BMI of 30 or more, or 27 to under 30 with at least one weight-related condition
Participants randomised
338
Duration
48 weeks
Primary endpoint
Percent change in body weight from baseline at 24 weeks; 48 weeks secondary
Estimand
Not stated in the source read
Read out
26 June 2023

48-week figures (least-squares mean). At the 24-week primary endpoint the arms were -7.2%, -12.9%, -17.3% and -17.5% against -1.6% on placebo. The abstract reports gastrointestinal events as the most common, dose-related and mostly mild to moderate, without rates; rates by arm are in the full text, not read here.

  • Jastreboff AM et al. N Engl J Med 2023;389:514-526 open · checked 23 September 2026
  • ClinicalTrials.gov NCT04881760 open · checked 23 September 2026
  • Registry: NCT04881760

Questions

Retatrutide phase 2 (Jastreboff), answered

What did Retatrutide phase 2 (Jastreboff) find?

In Retatrutide phase 2 (Jastreboff), a phase 2 trial of retatrutide in adults with a BMI of 30 or more, or 27 to under 30 with at least one weight-related condition (n=338), mean body weight fell 8.7% on 1 mg, 17.1% on 4 mg (pooled), 22.8% on 8 mg (pooled) and 24.2% on 12 mg over 48 weeks, against 2.1% on placebo (Jastreboff AM et al. N Engl J Med 2023;389:514-526).

What side effects were reported in Retatrutide phase 2 (Jastreboff)?

Retatrutide phase 2 (Jastreboff): The abstract reports gastrointestinal events as the most common, dose-related and mostly mild to moderate, without rates; rates by arm are in the full text, not read here.