The results of the second study, conducted at the Presbiterian Hospital of New York and at the Weill Cornell Medical Center, were presented on 17 0ctober at 36th Annual Meeting of the Neuroscience Association at Atlanta.

Both were phase I studies designed primarily to assess the safety of the treatment in 12 patients and both used a non-pathogen adenovirus as a vector.

In the first study the product, CERE-120, resorted to a viral vector carrying the gene of neurturin, a protein that has the function of keeping dopaminergic neurons active and vital.  Neurturin belongs to the family of growth factors for nervous tissue derived from glial cells (GDNF) and shares their pharmacological properties.  The patients who received the lowest dose improved by 40% after 9 months, whereas those who received a dose that was 4 times higher improved to the same extent, but 3 months earlier.  The time in OFF diminished by  50% and the time in good quality ON doubled.

In the second study, which lasted a year, a product of Neurologix Inc. was used, which contains a viral vector carrying the GAD gene (glutamic acid decarboxylase), which was inserted into the subthalamic nucleus.  Three dose levels were used, each given to 4 patients.  No side effects were recorded.  Overall, the clinical improvement amounted to  25%; a 37% improvement was recorded in 9 patients and a 40 to 65% improvement in 5 patients.  PET (positron emissioni  tomography) findings revealed significant improvement in brain metabolism.

It is too early for great enthusiasm, as these findings have to be confirmed in a larger number of patients in a controlled trial.  Nevertheless, the change from purely symptomatic therapy to therapy that modifies the disease itself is worthy of unconditional interest.

Marks WJ (UCSF); During MJ (Neurologix)