GCG and type 1 diabetes mellitus: Subject 3 who had T1D 10 years at the time of study, still achieved modest improvements including an increase in fasting C-peptide from 0.25 ng/ml at basal to 0.36 ng/ml at 56 weeks and an increase in glucagon-stimulated C-peptide level from 0.4 ng/ml at basal to 0.52 ng/ml at 26 weeks (Fig. 6c).