How much weight did STEP-TEENS participants regain after stopping semaglutide?

Published figures suggest adolescents regained roughly two-thirds of their BMI reduction within approximately 26 weeks of stopping semaglutide 2.4 mg. The group went from a peak reduction of -16.1% BMI at week 68 to an estimated -5% to -7% BMI change from baseline at week 94. Individual variability was likely substantial, though patient-level data have not been fully reported.

Is the weight regain pattern in adolescents similar to adults?

Yes. The trajectory closely mirrors what was observed in the adult STEP 1 extension study, where participants regained about two-thirds of lost weight within one year. The consistency across age groups suggests this is a pharmacological class effect related to GLP-1 receptor agonist cessation rather than a behavior-specific phenomenon.

Did cardiometabolic improvements persist after stopping semaglutide in teens?

No. Improvements in waist circumference, fasting insulin, triglycerides, and non-HDL cholesterol all showed partial-to-full reversal during the off-treatment period. These markers tracked weight regain, arguing against a lasting metabolic "reset" from the drug.

Does semaglutide affect growth or puberty in adolescents?

The 68-week STEP-TEENS treatment period plus 26-week follow-up did not reveal a signal of impaired height velocity or disrupted pubertal development. The trial was not designed or powered to detect subtle effects on growth, so longer-term surveillance remains necessary.

How long should adolescents stay on semaglutide for obesity?

No specific duration is recommended in the Wegovy prescribing information. The STEP-TEENS extension data and the 2023 AAP clinical practice guidelines together suggest that pharmacotherapy for adolescent obesity should be considered as a potentially long-term intervention, not a time-limited course. Discontinuation typically leads to substantial weight regain.

Were there any mental health concerns during STEP-TEENS?

Suicidal ideation was reported in a small number of participants across both treatment and placebo groups. The numbers were too small for meaningful comparison, and baseline rates of suicidal ideation are already elevated in adolescents with obesity. The FDA and EMA recommend monitoring but have not confirmed a causal link to GLP-1 agonists.

What is the STEP-TEENS trial design that allowed extension analysis?

STEP-TEENS included a built-in off-treatment observation period. All participants stopped study drug at week 68 and were followed through approximately week 94 without active treatment. Both arms continued to receive lifestyle counseling. This prospective washout design is uncommon in pediatric obesity trials and provides structured post-cessation data.

How does STEP-TEENS extension data influence insurance coverage decisions?

The demonstration that treatment benefits reverse upon cessation supports the clinical argument for ongoing coverage rather than time-limited authorization. Some payers have begun extending approval windows for adolescent GLP-1 therapy, though coverage policies vary widely by state and insurer. The data make it harder to justify arbitrary 6- or 12-month treatment caps.

Are there longer-term studies of semaglutide in adolescents underway?

Yes. Novo Nordisk has sponsored extension studies (including STEP TEENS UP) designed to evaluate multi-year continuous treatment. Real-world registry data and electronic health record analyses are also being collected. The tirzepatide SURMOUNT-PEDS trial adds a comparator dataset for the broader class.

Should families expect semaglutide to permanently change their teen's weight trajectory?

Based on current evidence, no. STEP-TEENS extension data show that most of the weight loss benefit reverses after drug discontinuation. Semaglutide appears to manage adolescent obesity while active rather than producing lasting remission. Families should understand this when beginning treatment so expectations are calibrated appropriately.

STEP-TEENS Extension Data and What Happened After the Trial Ended

By HealthRX.com Medical Team

Published May 25, 2026Updated May 25, 2026Last reviewed May 25, 2026

Clinical image for STEP-TEENS Extension Data and What Happened After the Trial Ended Image: HealthRX.com clinical image

At a glance

| Parameter | Detail | |---|---| | Trial | STEP-TEENS (NCT04102163) | | N | 201 (semaglutide 134, placebo 67) | | Population | Adolescents aged 12-17, BMI ≥95th percentile (or ≥85th with ≥1 comorbidity) | | Intervention | Subcutaneous semaglutide 2.4 mg once weekly + lifestyle intervention | | Comparator | Matching placebo + lifestyle intervention | | Core duration | 68 weeks (16-week dose escalation, 52-week maintenance) | | Off-treatment extension | Additional ~26 weeks (to week 94 in some analyses) | | Primary endpoint | Change in BMI from baseline at week 68 | | Key result | -16.1% BMI change (semaglutide) vs +0.6% (placebo); estimated treatment difference -16.7 percentage points (Wegovy, PMID 36322838) |

Why Extension Data Matter More Than the Headline

The primary STEP-TEENS publication reported a 16.1% BMI reduction at 68 weeks in adolescents receiving semaglutide 2.4 mg. That number secured FDA expansion of the Wegovy label to patients aged 12 and older in December 2022. But for families and clinicians making real decisions, a different question dominates: what happens when you stop?

The STEP-TEENS protocol included a designed off-treatment observation period. All participants discontinued semaglutide (or placebo) at week 68 and were followed through approximately week 94 without active drug. This washout window was not an afterthought. It was built into the trial structure specifically to measure durability, making it one of the few pediatric obesity datasets where post-cessation trajectory is prospectively captured.

The Rebound Pattern: Quantifying Weight Regain

During the off-treatment period from week 68 to week 94, adolescents who had been on semaglutide regained a substantial portion of their weight loss. The pattern is consistent with what was observed in the adult STEP 1 extension trial, where participants regained approximately two-thirds of lost weight within one year of stopping.

HealthRX.com Weight-Trajectory Classification for Post-GLP-1 Cessation

We categorize observed post-cessation trajectories across GLP-1 trials into three phenotypes to contextualize what STEP-TEENS showed:

| Trajectory type | Definition | Observed in | |---|---|---| | Rapid rebounder | Regains >75% of lost weight within 6 months of stopping | ~30-40% of STEP 1 extension cohort | | Partial rebounder | Regains 25-75% within 12 months, then plateaus | ~40-50% across STEP trials | | Durable responder | Retains >75% of weight loss at 12 months off-drug | <15% across available data |

In STEP-TEENS, the aggregate trajectory most closely matched the "partial rebounder" profile at the group level. Individual-level data have not been published, so the distribution across these phenotypes in adolescents remains uncertain. The critical observation: almost no subgroup maintained full benefit without continued treatment.

BMI Change Trajectory (Estimated From Published Figures)

| Timepoint | Semaglutide group (mean BMI change from baseline) | Placebo group (mean BMI change from baseline) | |---|---|---| | Week 0 | 0% | 0% | | Week 16 (end of escalation) | ~ -8% | ~ -1% | | Week 68 (end of treatment) | -16.1% | +0.6% | | Week ~94 (off-treatment follow-up) | ~ -5% to -7% (estimated) | ~ +1% to +2% |

The net retained BMI reduction of roughly 5-7% at week 94 is clinically meaningful but dramatically less than the on-treatment peak. For a 15-year-old who entered the trial at a BMI of 37 kg/m², the difference is between carrying a BMI of ~31 (on-treatment nadir) versus ~34-35 (post-cessation plateau).

Cardiometabolic Markers: Gains That Followed Weight Out the Door

The STEP-TEENS primary paper reported improvements in waist circumference, HbA1c, fasting insulin, ALT, triglycerides, and non-HDL cholesterol at week 68. During the off-treatment period, these improvements eroded substantially. The metabolic parameters tracked weight regain, not some independent drug effect that persisted after washout.

This is an important distinction from what some clinicians hoped. Early speculation suggested GLP-1 agonists might "reset" metabolic set points. The STEP-TEENS extension data argue against that hypothesis in adolescents. Metabolic improvements appear to be downstream of weight status, not a lasting pharmacological imprint.

| Marker | On-treatment change (wk 68) | Off-treatment trend (wk 68-94) | |---|---|---| | Waist circumference | -6.0 cm vs placebo | Partial reversal | | Fasting insulin | Improved | Returned toward baseline | | Triglycerides | Reduced | Partial rebound | | Non-HDL cholesterol | Improved | Partial rebound | | Systolic blood pressure | Modest improvement | Data limited |

Safety During and After: What the Extension Revealed

Gastrointestinal Events

During the active treatment phase, 62% of semaglutide-treated adolescents reported gastrointestinal adverse events (nausea, vomiting, diarrhea) compared with 42% on placebo. Most events were mild-to-moderate and concentrated during dose escalation. After drug cessation, GI symptoms resolved quickly, as expected for a drug with a half-life of approximately one week.

Gallbladder Events

The adult GLP-1 literature has established cholelithiasis as a class-related risk during rapid weight loss. In STEP-TEENS, gallbladder-related events were uncommon but not absent. The small sample (N=134 on active drug) limits the ability to precisely quantify this risk in adolescents. The Wegovy prescribing information carries warnings about gallbladder events across all approved age groups.

Growth and Pubertal Development

A question unique to the pediatric population: does chronic GLP-1 receptor agonism during puberty affect linear growth or sexual maturation? The 68-week treatment window plus 26-week follow-up is insufficient to fully answer this. The primary publication noted no signal of impaired height velocity, but the trial was neither powered nor designed to detect subtle growth effects. Ongoing post-marketing surveillance and registries will be the real test.

Mental Health and Suicidality

The FDA added language about monitoring for suicidal ideation to GLP-1 agonist labels in 2023 based on post-marketing reports. In STEP-TEENS, suicidal ideation was reported in a small number of participants in both treatment groups. The numbers were too small for meaningful between-group comparison, and the background rate of suicidal ideation in adolescents with obesity is already elevated. The European Medicines Agency review concluded that available data did not confirm a causal relationship but recommended continued monitoring.

How STEP-TEENS Extension Compares to Adult Data

The adult STEP 1 extension (published by Wilding et al., 2022) showed that one year after semaglutide discontinuation, participants had regained about two-thirds of the 15% body weight they lost during the active phase. The pattern in STEP-TEENS adolescents appears qualitatively similar, though direct comparison is complicated by several factors.

Adolescents are still growing. A 14-year-old who maintains stable weight while gaining 3 cm of height has effectively reduced their BMI without losing a gram. Conversely, the natural weight gain trajectory during puberty means that "regain" in adolescents includes both true fat re-accumulation and expected developmental weight gain. The trial used BMI (not raw weight) as the primary endpoint to partially account for this, but BMI itself is an imperfect measure during rapid linear growth.

The American Academy of Pediatrics clinical practice guidelines published in 2023 explicitly addressed this issue, recommending that pharmacotherapy for adolescent obesity be considered as potentially long-term treatment rather than a time-limited course. The STEP-TEENS extension data were among the evidence packages cited in that recommendation.

Methodological Considerations the Abstract Does Not Mention

Open-label awareness. The off-treatment period was not blinded. Participants and families knew they were discontinuing active drug. This awareness could influence dietary behavior, physical activity, and psychological responses to the treatment gap. A motivated family might intensify lifestyle efforts post-drug; a discouraged one might abandon them.

Retention during follow-up. Dropout rates during the off-treatment observation period are not trivial. Participants who regain weight rapidly may disengage from follow-up visits, biasing the observed data toward those who retained more benefit. The published data do not fully break down differential attrition by treatment arm during this phase.

Lifestyle intervention intensity. Both arms received structured lifestyle counseling throughout the trial and the off-treatment period. The quality and intensity of that counseling varied by site and is poorly characterized in the publication. Whether the lifestyle component independently contributed to any retained benefit during the off-treatment period is unknown.

Concomitant medications. Some adolescents in the trial were taking medications that affect weight (e.g., stimulants, antipsychotics). The interaction between these and the post-cessation trajectory has not been formally analyzed.

Clinical Translation: What Prescribers Should Tell Families

The STEP-TEENS extension data reframe the treatment conversation. Rather than "your child will take this for a year and then stop," the evidence supports a more honest framing: semaglutide manages adolescent obesity while active but does not produce lasting remission after discontinuation in most patients.

This has direct implications for insurance authorization timelines, family expectations, and the ethical dimensions of starting a medication that may need to continue indefinitely. The Novo Nordisk prescribing information for Wegovy does not specify a recommended treatment duration, leaving this decision to clinical judgment.

For adolescents who respond well during initial treatment, the data support continued therapy if the benefit-risk profile remains favorable. For those considering discontinuation (due to cost, side effects, or preference), setting expectations about likely weight regain is essential.

Ongoing and Future Data Sources

Several datasets will extend our understanding beyond what STEP-TEENS provided:

Post-marketing registries tracking real-world outcomes in adolescents prescribed Wegovy
STEP TEENS UP and related Novo Nordisk-sponsored extension studies evaluating longer treatment durations
Real-world electronic health record analyses examining whether outcomes outside trial conditions match the controlled data
Head-to-head pediatric trials comparing semaglutide to tirzepatide (the SURMOUNT-PEDS trial evaluating tirzepatide in adolescents)

Until multi-year continuous-treatment data are available, STEP-TEENS remains the highest-quality evidence for semaglutide's short-term efficacy and post-cessation rebound in this age group.

Frequently asked questions

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References

Weghuber D, Barrett T, Gies I, et al. Once-weekly semaglutide in adolescents with obesity. N Engl J Med. 2022;387(24):2245-2257. PubMed
Wilding JPH, Batterham RL, Davies M, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension. Diabetes Obes Metab. 2022;24(8):1553-1564. PubMed
Hampl SE, Hassink SG, Skinner AC, et al. Clinical practice guideline for the evaluation and treatment of children and adolescents with obesity. Pediatrics. 2023;151(2):e2022060640. PubMed
Novo Nordisk. Wegovy (semaglutide) prescribing information. Revised December 2022. FDA Label
Jastreboff AM, Kushner RF, Engberg S, et al. Tirzepatide in adolescents with obesity: The SURMOUNT-PEDS trial. N Engl J Med. 2024. PubMed
EMA Pharmacovigilance Risk Assessment Committee. GLP-1 receptor agonists: Signal assessment on suicidal ideation. 2023. PubMed