GCG and type 2 diabetes mellitus: In patients with T2DM, serum levels of glucose, insulin and C-peptide, and plasma levels of GLP-1, GLP-2 and PYY were assessed pre-dose (day −1) and post-dose (days 14 and 28), in a fasting state (1 h and immediately before an MTT on days −1, 14 and 28) and in response to an MTT (30-min intervals up to 3 h after the MTT on days −1, 14 and 28).