GCG and type 1 diabetes mellitus: Closed loop bi-hormonal artificial pancreas systems, such as the artificial pancreas (APTM) developed by Inreda Diabetic B.V. (Goor, The Netherlands), fully regulate blood glucose levels of type 1 diabetes mellitus (T1DM) patients by administration of insulin and glucagon using a closed loop regulator as shown in Figure 1 [1].