Here's the link, with significant text quoted-if I read this correctly, it's already in clinical use (what does that mean? not sure, but it sounds good) and crosses the bbb, woo-hoo...:

http://7thspace.com/headlines/281918...s_disease.html

"Conclusions: The apparent ability of EX-4 to arrest progression of, or even reverse nigral lesions once established, suggests that pharmacological manipulation of the GLP-1 receptor system could have substantial therapeutic utility in PD.

Critically, in contrast to other peptide agents that have been demonstrated to possess neuroprotective properties in pre-clinical models of PD, EX-4 is in current clinical use in the management of type-II diabetes and freely crosses the blood brain barrier; hence, assessment of the clinical efficacy of EX-4 in patients with PD could be pursued without delay.
Author: Alexander Harkavyi, Amjad Abuirmeileh, Rebecca Lever, Ann E Kingsbury, Christopher S Biggs and Peter S Whitton
Credits/Source: Journal of Neuroinflammation 2008, 5:19"