Semaglutide 1.7 mg shows comparable BMI reduction to 2.4 mg in adolescents and adults

This analysis used a model-informed drug development approach, combining simulation analyses with data from the Phase 3 STEP TEENS study in adolescents and pooled adult semaglutide STEP studies. The population included adolescents and adults with obesity. The intervention was semaglutide 1.7 mg, with comparators being semaglutide 2.4 mg and placebo. The primary outcome was BMI effects over a 68-week follow-up period.

The main results showed that semaglutide 1.7 mg had comparable efficacy to the 2.4 mg dose. For mean BMI change, the effect was -15.2% versus -17.4% for the 2.4 mg dose, with a p-value of p < 0.01 versus placebo, indicating a greater reduction than placebo. Semaglutide concentrations were similar between adolescents and adults, though the effect size was not reported. Proportions achieving prespecified BMI reduction thresholds and gastrointestinal AE profiles were similar across populations and doses.

Key secondary outcomes included exposure, tolerability, and gastrointestinal adverse event (AE) incidence. The tolerability of semaglutide 1.7 mg was comparable to the 2.4 mg dose. Safety findings indicated that gastrointestinal AE incidence was the primary adverse event measure; serious adverse events and discontinuations were not reported.

These results compare to prior landmark studies in obesity, such as the adult STEP trials, which established semaglutide 2.4 mg efficacy. This analysis extends findings to adolescents, supporting the November 2024 Wegovy label approval for adolescents ≥12 years with the 1.7 mg dose.

Key methodological limitations include the reliance on simulation analyses and extrapolated data, as noted in the certainty. The study setting was not reported, and funding or conflicts were not reported, which may introduce potential biases.

Clinically, these results support the use of semaglutide 1.7 mg for weight management in adolescents and adults, but the modeled nature means real-world effectiveness may vary. Practice decisions should consider this as supportive evidence for label approval.

Unanswered questions remain about long-term outcomes beyond 68 weeks, real-world safety in broader populations, and comparative effectiveness against other obesity interventions.