30 June 2004. BioWorld Online
today reported that a phase 2 trial of the neurotrophic factor GDNF failed to improve symptoms in people with Parkinson's disease. The results of this trial, by the biotechnology company Amgen, differ from positive results of a smaller, open-label study of the same compound in England. The 34 patients in the present trial received infusion of cell-derived GDNF or placebo into the putamen region of their brain. The drug was found to be well-tolerated and appeared to alter brain function, yet after six months did not produce an improvement in the patient’s scores of the Unified Parkinson's Disease Rating Scale, according to BioWorld. Amgen did not publicly announce whether it will continue this program. Prior clinical trials of growth factors failed because of intolerable side effects.—Gabrielle Strobel.