NNZ-2566: a Gly-Pro-Glu analogue with neuroprotective efficacy in a rat model of acute focal stroke.

The N-terminal cleavage product of human insulin-like growth factor-1 (IGF-1) in the brain is the tripeptide molecule Glypromate (Gly-Pro-Glu). Glypromate has demonstrated neuroprotective effects in numerous in vitro and in vivo models of brain injury and is in clinical trials for the prevention of cognitive impairment following cardiac surgery. NNZ-2566 is a structural analogue of Glypromate, resulting from alpha-methylation of the proline moiety, which has improved the elimination half-life and oral bioavailability over the parent peptide.