Table 2. Outcomes in randomized trials of neuroregenerative and/or cell-transplantation strategies for Parkinson's disease.

Agent	Outcome	Source
CERE-120	No significance vs. sham on 1° endpoint	[43]
GDNF (intraventricular delivery)	No significance vs. sham on 1° outcome; toxicity	[44]
GDNF (initraputamenal delivery)	No significance vs. sham on 1° endpoint	[45]
Embryonic mesencephalic tissue	No significance vs. sham on 1° endpoint; toxicity	[46]
Embryonic mesencephalic tissues	No significance vs. sham on 1° endpoint; toxicity	[47]
Fetal porcine ventral mesencephalic tissue	No significance vs. sham	[48]
Retinal epithelial pigmented cells	No significance vs. sham	[49]