OBJECTIVE: The primary objective of the present study was to investigate the safety, tolerability, and pharmacokinetics of a single dose of NN2211, a long-acting glucagon-like peptide 1 (GLP-1) derivative, in healthy male subjects. The secondary objective was to investigate the pharmacodynamics of NN2211. RESEARCH DESIGN AND METHODS: In a double-blind, randomized dose, escalation, placebo-controlled study, healthy male subjects were enrolled at eight consecutive dose levels (1.25, 2.5, 5.0, 10.0, 12.5, 15.0, 17.5, and 20.0 microg/kg) with eight subjects per dose level at a 3:1 active:placebo randomization. After subcutaneous dosing with NN2211, 48-h pharmacokinetic, and 24-h glucose, insulin and glucagon profiles were assessed. In addition, three subjects at each dose level were randomly assigned (one placebo/two active) to an intravenous glucose tolerance test (IVGTT) 9 h after the dose (corresponding to the time to maximal plasma concentration of NN2211). RESULTS: After subcutaneous administration, the half-life of NN2211 was found to be 11-15 h. Overall, although there were no statistically significant differences compared with placebo in the area under the curve (0-9 h for insulin or glucagon), there was a borderline- significant lowering of glucose levels (P = 0.066). During the IVGTT, there was a statistically significant increase in insulin secretion (P = 0.0002), but there was no significant effect on glucagon levels. Although no significant effect was observed on glucose levels during the IVGTT, there was a dose-dependent increase in the glucose disappearance constant. Whereas no serious adverse events were observed, there was a higher incidence of adverse events after active treatment compared with placebo treatment (notably headache, dizziness, nausea, and vomiting). CONCLUSIONS: This study provides evidence that NN2211 has a pharmacokinetic profile consistent with once-daily dosing in humans.