18+ · Research use only
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).
Primara Labs sells some of the compounds covered here. Every figure on this page links to its source and the date it was checked.
Updated 24 September 2026
Results
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.
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.