- Children and adolescents with type 1 diabetes mellitus (T1DM) for at least 1 year confirmed by typical symptoms at diagnosis and/or by antibody testing (presence of anti-GAD (glutamic acid decarboxylase) or anti-IA2 (islet antigen 2/tyrosine phosphatase) or anti-islet cell antibodies) and/or clinical features (eg, history of ketoacidosis).