Second chance

In 2004 Parkinson's disease research seemed on the verge of a breakthrough. California-based Amgen was delivering a protein directly into the brains of 34 people with the disease. The protein, glial cell line - derived neurotrophic factor, or GDNF, had for years been a promising candidate to treat Parkinson's and other brain disorders. But attempts to use it and other such proteins had met with crushing disappointment. But on 28 June 2004, Amgen announced that its trial was a bust. Not only had GDNF infusion failed to improve the symptoms of Parkinson's disease, it had raised serious safety concerns. Three years on, however, another California-based company, backed largely by venture capitalists and the Michael J. Fox Foundation for Parkinson's Research, is reviving the therapy with a significant difference. Ceregene, is using gene therapy - which has yet to live up to its initial promise - to get growth factors into the brain. In essence, it is combining two experimental therapies that have never consistently worked - and could end up reviving both, the company's founders optimistically suggest.