The first studies of human gene therapy for Parkinson’s disease have shown that the technique is safe and can reduce symptoms for patients, two groups of researchers report.
Each of the 24 patients who received therapy in the two separate trials received some benefit, and none had any significant side effects, researchers reported at neuroscience meetings Tuesday and last week.
Gene therapy has a tarnished reputation because of problems encountered in trials against other diseases, said Katie Hood, deputy chief executive officer of the Michael J. Fox Foundation for Parkinson’s Research.
The Food and Drug Administration temporarily halted gene- therapy trials in 1999 when an 18-year-old being treated for a mild genetic disorder died after a violent reaction to the procedure. Trials were halted again in 2005 after three French children being treated for inherited immunodeficiency disease developed leukemia and one died.
“It’s very encouraging that two companies were able to show benefits with no significant adverse effects,” Hood said.
Experts and the researchers themselves, however, cautioned patients against investing too much hope in the findings because Parkinson’s studies are notorious for showing placebo effects.
Only when techniques are tested in controlled trials now in the planning stages will researchers determine whether the benefits are real and long-lasting.
