Semaglutide as an adjunct in T1D
Novo Nordisk
Promising adult T1D adjunct evidence; obesity treatment and T1D approval are different questions.
What it is
Randomized studies in adults with T1D using automated insulin delivery found improved glucose outcomes, weight and insulin requirements. Evidence is strongest in adults with obesity; there is no T1D glycemic indication, and ketosis and hypoglycemia still require attention.
Editorial review: . What was checked and what remains uncertain.
Latest dated source in the citation list: 2025-12-22. This is the source’s date, not a new review of every claim.
Trial status, labels and access can change between reviews.
Evidence behind this assessment
Key evidence notes. Study results, product eligibility and access answer different questions.
- Who was studied?
- Study populations and analysis groups vary. Product age limits alone do not describe who was studied.See the linked studies and their populations →
- Benefit or performance
- Glycemic benefit: Editorial estimate: ADJUST-T1D found +8.8 percentage points of time in range and −0.3 percentage points HbA1c versus placebo, in adults with obesity using AID.[1]
- Important harms and treatment burden
- Safety: Editorial estimate: no DKA in ADJUST-T1D, but two severe hypoglycemia events per arm; crossover study recorded two episodes of euglycemic ketosis without acidosis. Small selected trials cannot establish rare-event safety.[2]
- Approval and country access
- Marketed for other indications; obesity-label eligibility, prescribing and coverage must be checked separately.Approval, trial recruitment, local supply and funding are separate. Check the cited label or access source.
- Follow-up and remaining uncertainty
- Read the record-specific review limits for gaps in evidence, source access or availability checks.
Research status alone does not establish approval, clinical benefit or local availability.
Editorial score: calculation and evidence
A weighted editorial judgment on a 0–100 scale, not a probability of success or a measured treatment effect. Higher criterion scores mean more favorable assessments.
Default calculation: 63 × 25 + 45 × 25 + 78 × 15 + 48 × 20 + 32 × 15 = 5310; divide by total weight 100. Unrounded weighted result: 53.1.
Editorial estimate: ADJUST-T1D found +8.8 percentage points of time in range and −0.3 percentage points HbA1c versus placebo, in adults with obesity using AID.[1]
Editorial estimate: no DKA in ADJUST-T1D, but two severe hypoglycemia events per arm; crossover study recorded two episodes of euglycemic ketosis without acidosis. Small selected trials cannot establish rare-event safety.[2]
Editorial estimate: ADJUST-T1D found a placebo-adjusted 8.8 kg weight difference; insulin requirements fell. T1D cardiovascular or kidney outcome protection is not established.[1]
Editorial estimate: two randomized T1D studies support an adjunct signal, with limited sample sizes and follow-up. They do not establish benefit for all ages, body sizes or delivery methods.[1]
Editorial estimate: no T1D glucose-treatment indication. Obesity treatment eligibility is separate; ADA 2026 supports applying GLP-1-based obesity management to eligible adults with T1D, with insulin adjustment and safety monitoring.[4]
These are scored as add-ons to insulin in Type 1 diabetes, never on their Type 2 diabetes evidence — a drug with a large Type 2 trial base but only small Type 1 studies scores low on maturity. Safety carries heavy weight here because the best-known adjunct risk, diabetic ketoacidosis at normal glucose levels, is potentially fatal and specific to Type 1. Most of this class is used off-label; that is reflected in access, not hidden.
Editor’s take
A material omission from the evidence map: randomized T1D results deserve visibility, with their adult/AID/obesity limits and safety findings kept in view.
The full picture
What the randomized studies found
ADJUST-T1D enrolled 72 adults with T1D, obesity and AID for 26 weeks. Semaglutide up to 1 mg weekly increased time in 70–180 mg/dL (3.9–10.0 mmol/L) by 8.8 percentage points versus placebo, reduced HbA1c by 0.3 points and weight by 8.8 kg. The composite glucose-and-weight target was reached by 36% versus 0%. Severe hypoglycemia occurred twice in each group; no DKA was reported.1
A separate crossover trial randomized 28 adults, of whom 24 completed. Time in range improved by 4.8 percentage points. Two episodes of recurrent euglycemic ketosis without acidosis occurred; this is not the same as DKA, but it is a relevant insulin-deficiency warning.2
A post hoc ADJUST analysis found a 22.6% reduction from baseline in daily insulin requirements, mainly bolus insulin. This is an analysis of the same trial, not another independent trial.3
Scope and access
Semaglutide remains an adjunct to insulin; these studies do not support replacing insulin or extrapolating to children or people without obesity. Treatment of obesity under an applicable product label is distinct from a T1D glycemic indication. The ADA’s 2026 guidance supports GLP-1-based obesity management in eligible adults with T1D; clinical support is needed for changing insulin requirements, gastrointestinal effects and ketone safety.4
Scores above are editorial comparisons of the T1D evidence, not measured efficacy percentages or prescribing recommendations.
References
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Shah et al. ADJUST-T1D. https://pubmed.ncbi.nlm.nih.gov/40550013/ ↩
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Pasqua et al. Nature Medicine (2025). https://www.nature.com/articles/s41591-024-03463-z ↩
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ADJUST-T1D post hoc insulin analysis. https://doi.org/10.2337/dc25-2249 ↩
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ADA Standards of Care 2026, obesity section. https://diabetesjournals.org/care/article/49/Supplement_1/S166/163915/8-Obesity-and-Weight-Management-for-the-Prevention ↩
Sources
- [1]Semaglutide in Adults with Type 1 Diabetes and Obesity (ADJUST-T1D) · peer-reviewed · 2025-06-23
- [2]Semaglutide with AID in T1D: randomized crossover trial · peer-reviewed · 2025-01-10
- [3]ADJUST-T1D post hoc analysis of insulin-dose reduction · peer-reviewed · 2025-12-22
- [4]ADA Standards of Care 2026: obesity management in T1D · peer-reviewed