The 2026 BELIEVE publication reported greater weight reductions with selected bimagrumab and semaglutide regimens than placebo. Bimagrumab remained described as investigational in that paper; the trial is evidence about specific regimens in adults with obesity.[1]
- Randomized
- 507 adults
- Groups
- 9
- Blinded period
- 48 weeks
How was BELIEVE designed?
BELIEVE randomized 507 adults across nine groups. The blinded phase lasted 48 weeks and was followed by an open-label extension. The population excluded diabetes.[1]
An extension is a distinct part of a study. When interpreting a number, identify which period it belongs to and whether the conditions of comparison remained the same.
What did selected groups show?
For the higher regimens summarized in the abstract, the reported least-squares mean body-weight changes at week 48 were as follows.[1]
| Group | Change |
|---|---|
| Bimagrumab | −9.3 kg |
| Semaglutide | −14.2 kg |
| Combination | −17.8 kg |
| Placebo | −3.3 kg |
What safety context was reported?
Common bimagrumab adverse events included muscle spasms, diarrhea, and acne. The paper also reported adverse events associated with semaglutide.[1]
Safety comparisons require the full participant counts, exposure periods, and event definitions. A list of common events does not answer every question about long-term use or a different population.
What can a combination trial establish?
A multi-arm trial can help separate what happens with individual interventions from what happens with their combination. The distinction should remain visible when the findings are summarized. A combination result cannot simply be credited to one component.
Compare this design with the earlier 2021 bimagrumab study, which emphasized fat mass in adults with type 2 diabetes. Different populations and endpoints make the studies complementary, not interchangeable. For a structured comparison, use the trial-reading framework.
Questions, answered.
Are these results for every dose or study arm?
No. The table presents selected regimens summarized in the abstract. The original paper contains the complete design and results.
Does the trial provide an individual weight-loss prediction?
No. Group estimates in a clinical study do not predict a particular person’s outcome.
Sources & further reading
Primary research and official records used for this page. Study results apply to the populations and interventions described.
- Bimagrumab plus semaglutide alone or in combination for the treatment of obesity: a randomized phase 2 trialHeymsfield et al. · Nature Medicine · 2026 · BELIEVE trial