Wegovy (Semaglutide) for Type 1 Diabetes
Wegovy is not FDA-approved for type 1 diabetes, but emerging evidence supports its off-label use in carefully selected patients with type 1 diabetes and obesity (BMI ≥30 or ≥27 with comorbidities) who are on automated insulin delivery systems with continuous glucose monitoring. 1, 2
Regulatory Status and Current Guidelines
- Only pramlintide is FDA-approved as an adjunctive agent to insulin in type 1 diabetes; all GLP-1 receptor agonists including semaglutide remain investigational for this indication 3, 4
- The 2025 ADA guidelines acknowledge that GLP-1 RAs have been studied in type 1 diabetes showing potential benefits on body weight and glycemic metrics, particularly in patients with obesity 3, 1
- Semaglutide requires explicit informed consent regarding off-label use, intensive monitoring, and careful patient selection 1
Clinical Evidence Supporting Use
The most recent and highest quality evidence comes from the 2025 ADJUST-T1D trial, which demonstrated that semaglutide 1 mg weekly in adults with type 1 diabetes and obesity using automated insulin delivery achieved superior outcomes compared to insulin alone: 2
- 36% of semaglutide patients vs. 0% of placebo patients achieved the composite endpoint (CGM time-in-range >70%, time-below-range <4%, and ≥5% weight loss) 2
- Mean weight loss of 8.8 kg greater than placebo 2
- Improved time-in-range by 8.8 percentage points 2
- HbA1c reduction of 0.3 percentage points 2
- No diabetic ketoacidosis events reported 2
- Only two severe hypoglycemia events in each group 2
Real-world data from 2024 corroborates these findings: 5
- 50 patients with type 1 diabetes on semaglutide showed 7.9% BMI reduction and 15.9 lb weight loss over one year 5
- Improved HbA1c, reduced glucose variability (lower CV and SD), and increased time-in-range 5
- No difference in time-below-range or time-above-range compared to controls 5
Patient Selection Criteria
Ideal candidates for off-label semaglutide in type 1 diabetes include: 1
- BMI ≥30 kg/m² or ≥27 kg/m² with weight-related comorbidities 1, 6
- Using automated insulin delivery or insulin pump therapy 1
- Continuous glucose monitoring capability 1
- Intact hypoglycemia awareness and ability to recognize/treat low blood sugars 1
- Willingness and ability to perform frequent glucose monitoring and insulin dose adjustments 1
Critical Safety Protocols
Insulin dose management is mandatory to prevent hypoglycemia: 1
- Reduce total daily insulin dose by 10-20% at semaglutide initiation 1
- Monitor CGM data closely during the first 2-4 weeks for hypoglycemia patterns 1
- Ensure patients have glucagon available for emergency hypoglycemia management 1, 6
Patient education requirements: 1, 6
- Educate on signs and symptoms of diabetic ketoacidosis as a precautionary measure 1, 6
- While DKA risk is prominently associated with SGLT2 inhibitors in type 1 diabetes, it has not been prominently reported with GLP-1 receptor agonists 1
- Counsel on gastrointestinal side effects (nausea, vomiting, diarrhea) 6
Important Caveats
- Semaglutide does not preserve β-cell function in type 1 diabetes and should not be used for this purpose 1
- Liraglutide studies showed no impact on C-peptide during treatment, with worsening C-peptide loss after discontinuation 3
- Weight management pharmacotherapy should be continued long-term to maintain benefits, as discontinuation often results in weight regain and worsening cardiometabolic risk factors 1
- Limited long-term safety data exists in the type 1 diabetes population 6
Dosing Strategy
Start with standard titration schedule: 2