Inclusion Criteria:

1. Patients living with Type 1 diabetes:

   • adults aged 18 to 75 years old (included)
   • children/adolescents aged 7 or older

2. Total daily dose of insulin ≥ 10 units per day & weighing >22 Kg

3. Patient and their parent(s)/guardian(s) trained and able to count carb

4. Current or previous insulin pump user or patient treated with multiple insulin injections

5. Patient glycaemic target is not achieved or suboptimal according to international consensus: HbA1c level equal and greater than 7% and less than 12% at the time of enrolment, or TIR < 70%, or TBR >4%

6. Any type of rapid insulin with a total daily insulin in the range of 10-60 IU (unauthorized use of insulin supplements by pen injector): Humalog™, Lyumjev (insulin lispro injection), Novorapid (insulin aspart) or FIASP® (" faster insulin aspart ")

7. Subject and their parent(s)/guardian(s) able to receive and understand study information, give written informed consent, and easily participate to the trial

8. Subject and their parent(s)/guardian(s) affiliated to the French social security system

9. Subject and their parent(s)/guardian(s) have the cognitive ability and can successfully operate all study devices and can adhere to the protocol

Exclusion Criteria:

1. Patient unable to tolerate tape adhesive, catheter or had any unresolved adverse skin condition and intolerance to steel
2. Patient not willing to perform finger stick blood glucose measurements required by the system and/or routine diabetes management
3. Patient with behaviour/lifestyle not compatible with optimal management of insulin therapy or deemed to be at significant risk of severe events (e.g. severe hypoglycaemia, diabetic ketoacidosis)
4. Unstable diabetic retinopathy
5. Pregnant women or planning to become pregnant during the study or breast-feeding
6. Patient abusing alcohol
7. Patient using DPP-4 inhibitor, GLP-1 agonists, metformin, or SGLT2 inhibitors during the last 3 months prior screening
8. Patient already participating in another interventional study
9. Patient currently using a hybrid closed loop system or patient who has stopped usage of Hybrid Closed loop system for less than 3 months
10. Patient under the protection of justice or under guardianship or curatorship, or hospitalised under duress or admitted to a health or social care establishment for purposes other than those of this investigation.