--- title: "SURMOUNT-4: Tirzepatide Phase 3 Results | Primara Labs" url: https://www.primaralabs.com/research/trials/surmount-4 source: Primara Labs, markdown mirror of the HTML page --- # SURMOUNT-4 In SURMOUNT-4, a phase 3 trial of tirzepatide in adults with BMI of 30 or more, or 27 or more with a weight-related complication, excluding diabetes (n=670), mean body weight changed by -5.5% on continued tirzepatide, weeks 36 to 88 over 88 weeks, against +14.0% on switched to placebo (treatment-regimen estimand; Aronne LJ et al. JAMA 2024 (SURMOUNT-4)). 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 GLP-1 Weight Loss Plateau: What Trials Show (Philippines)1:46·[Transcript and chapters](https://www.primaralabs.com/videos/glp1-weight-loss-plateau) ## Results Mean percent change in body weight by arm, as each source reports it. Navy bars are the trial arms, grey bars the comparator. Bars from different trials are not a head-to-head comparison: populations, durations and estimands differ. ## Side effects reported In SURMOUNT-4, discontinuation because of adverse events was 1.8% on continued tirzepatide, weeks 36 to 88, against 0.9% on switched to placebo. The most frequently reported adverse events were diarrhoea in 10.7% on continued tirzepatide, weeks 36 to 88 against 4.8% on switched to placebo, nausea in 8.1% on continued tirzepatide, weeks 36 to 88 against 2.7% on switched to placebo and vomiting in 5.7% on continued tirzepatide, weeks 36 to 88 against 1.2% on switched to placebo. | Event | Continued tirzepatide, weeks 36 to 88 | Switched to placebo | | --- | --- | --- | | Discontinuation for adverse events | 1.8% | 0.9% | | Diarrhoea | 10.7% | 4.8% | | Nausea | 8.1% | 2.7% | | Vomiting | 5.7% | 1.2% | Design ## Trial design and sources Compound Tirzepatide Phase 3 Population Adults with BMI of 30 or more, or 27 or more with a weight-related complication, excluding diabetes Participants randomised 670 Duration 88 weeks Primary endpoint Mean percent change in weight from week 36 (randomization) to week 88 Estimand treatment-regimen Read out 1 January 2024 Withdrawal design: a 36-week open-label lead-in on tirzepatide, then randomisation to continue or switch to placebo. The switch-to-placebo arm regained weight. Adverse events shown are the double-blind period. - Aronne LJ et al. JAMA 2024 (SURMOUNT-4) [open](https://doi.org/10.1001/jama.2023.24945) · checked 23 September 2026 - ClinicalTrials.gov NCT04660643 [open](https://clinicaltrials.gov/study/NCT04660643) · checked 23 September 2026 - Registry: NCT04660643 Questions ## SURMOUNT-4, answered ### What did SURMOUNT-4 find? In SURMOUNT-4, a phase 3 trial of tirzepatide in adults with BMI of 30 or more, or 27 or more with a weight-related complication, excluding diabetes (n=670), mean body weight changed by -5.5% on continued tirzepatide, weeks 36 to 88 over 88 weeks, against +14.0% on switched to placebo (treatment-regimen estimand; Aronne LJ et al. JAMA 2024 (SURMOUNT-4)). ### What side effects were reported in SURMOUNT-4? In SURMOUNT-4, discontinuation because of adverse events was 1.8% on continued tirzepatide, weeks 36 to 88, against 0.9% on switched to placebo. The most frequently reported adverse events were diarrhoea in 10.7% on continued tirzepatide, weeks 36 to 88 against 4.8% on switched to placebo, nausea in 8.1% on continued tirzepatide, weeks 36 to 88 against 2.7% on switched to placebo and vomiting in 5.7% on continued tirzepatide, weeks 36 to 88 against 1.2% on switched to placebo. Related ## More on tirzepatide - [TRIUMPH-5](https://www.primaralabs.com/research/trials/triumph-5) - [SURMOUNT-1](https://www.primaralabs.com/research/trials/surmount-1) - [SURMOUNT-2](https://www.primaralabs.com/research/trials/surmount-2) - [SURMOUNT-3](https://www.primaralabs.com/research/trials/surmount-3) - [SURMOUNT-5](https://www.primaralabs.com/research/trials/surmount-5) - [Evidence Map: Tirzepatide](https://www.primaralabs.com/research/evidence#tirzepatide) - [Tirzepatide 15mg](https://www.primaralabs.com/marketplace/tirzepatide-15mg)