Age 18–40 years, history of T1D ≥2 years and ≤16 years, HbA1c ≥7.5% (58 mmol/mol) and ≤10.5% (91 mmol/mol), fasting serum C-peptide <0.1 pmol/mL, and daily insulin requirements <100 IU. Here, INS is linked to type 1 diabetes mellitus.