Between 16% and 22% of type 1 diabetic patients present a clinical and biological profile of insulin resistance favored by a family history of type 2 diabetes or metabolic syndrome. They constitute a group of patients with "double diabetes" since they have both true type 1 diabetes and inherited insulin resistance, typical of type 2 diabetes.

For several years, GLP1 agonists have been successfully used in the treatment of type 2 diabetes, leading to very significant improvements in glycemic control and weight loss.

Because of the insulin-sensitizing power of GLP1 agonists, the investigators hypothesize that they could reduce insulin resistance in patients with "double diabetes" and thus improve their glycemic control.

The investigators propose to use in this study semaglutide, the most recent and most potent GLP1 agonist (superiority demonstrated compared to exenatide LP and dulaglutide) and administered as a weekly subcutaneous injection (in contrast to liraglutide administered daily).

Inclusion Criteria:

• Person who has given written consent

• Patient over 18 years of age

• Patient with type 1 diabetes confirmed by a C-peptide below laboratory standards

• Age at diagnosis < 35 years

• Treated with optimized insulin therapy (multi-injections or pump) for at least 1 year, having received specific therapeutic education on insulin dose adaptation.

• BMI (weight/height2) ≥ 27 Kg/m².

• At least one of the following criteria:

  • Family history of type 2 diabetes (parents, grandparents, uncles, aunts, brothers and sisters)
  • Family history of obesity (BMI>30 Kg/m2) (parents, grandparents, uncles, aunts, siblings)
  • Triglycerides > 1.50g/l (1.7mmol/l)
  • HDL< 0.5 g/l (1.29 mmol/l) in women, HDL<0.4 g/l (1.03 mmol/l) in men

• HbA1c ≥ 7.5% and < 12% in the 3 months preceding inclusion

• Having continuous glucose monitoring by a CGM (Holter Glucose Monitoring) system: Guardian, Dexcom or Free Style Libre

• For women of childbearing age: using an effective method of contraception until 2 months after the end of treatment. Effective contraception includes: hormonal contraception, intrauterine device, bilateral tubal occlusion, vasectomy and sexual abstinence

Exclusion Criteria:

• person not affiliated to national health insurance
• Pregnant, parturient or breastfeeding woman
• HbA1c ≥12% in the 3 months preceding inclusion.
• Uncontrolled and potentially unstable diabetic retinopathy or maculopathy, confirmed by a fundus examination performed in the 6 months preceding the selection
• Person under a measure of legal protection (curatorship, guardianship)
• Renal insufficiency (GFR<30 ml/mn)
• Hepatic insufficiency (INR> 1.5)
• BMI >40 kg/m².
• History of bariatric surgery
• History of pancreatitis
• Allergy to the active substance or to one of the excipients of OZEMPIC®.
• Patients treated with GLP1 agonists or oral antidiabetics in the month preceding month prior to inclusion