Ramond T. Bartus, Ph.D. presented the newest findings of a clinical trial utilizing a new trreatment for Parkinson’s disease. Dr. Bartus is the Chief Scientific Officer and also the Executive Vice President of Ceregene, a San Diego based biotechnology company that is developing gene transfer treatments for neurodegenerative diseases. He was an invited speaker at the May 18th annual meeting of The American Society of Gene and Cellular Therapy which was held in Salt Lake City, Utah.
Dr. Bartus spoke about findings from the second and continuing clinical trial of Cere-120, his company’s gene therapy product to deliver the neurotrophic factor neurtuin to people affected by Parkinson’s disease. Cere-120 is the company’s name for AAV-neurturin. This is a novel way to deliver a neurotrophic factor the brains of Parkinson’s patients. Neurturin is a naturally occurring protein that has successfully repaired and restored injured or dying dopamine producing neurons. In Ceregene’s application, this protein is inserted into a harmless adeno-associated virus (AAV) and is delivered directly to the putamen or substantia nigra regions of the brain by stereotactic injection. Degeneration of neurons in these areas of the brain are responsible for the loss of dopamine and the motor impairments associated with Parkinson’s disease. Neurturin is one of three small proteins that are glial-cell line derived neurotrophic factors (GDNF) that have shown promise in restoring dopamine producing neurons. Neurotrophic factors are proteins responsible for the growth and maintenance of neurons. In both human autopsy and animal studies, it was found that Cere-120 , once delivered to the brain by this highly targeted injection, provides long term, stable and controlled neurturin expression.
Ceregene completed the first clinical trial of Cere-120 in 2009 that demonstrated safety and tolerability and showed some promise of alleviating some PD symptoms. This Phase 2b trial has shown stronger results, but not in all patients. Patients who have been diagnosed for 5 years or less and have not had any prior treatment had higher scores on the Unified Parkinson’s Disease Rating Scale (UPDRS) as well as in other measures of Parkinson’s such as quality of life. Some improvements of overall “off-time” and “on-time without troubling dyskinesias” in patients who had received prior treatment and had been diagnosed for up to 10 years were also noted, but the response was strongest in early-stage patients.
These findings demonstrate that this novel approach to treating neurodegenerative disease deserves more serious consideration and that more carefully planned clinical trials to enroll only early-stage, newly diagnosed and untreated patients will be necessary..Ceregene has conducted 6 clinical trials in both Parkinson’s and Alzheimers. Of 200 subjects enrolled, 100 have received gene therapy products with no serious safety issues. The company plans to continue research in neurotrophic factors via gene therapy delivery for neurodegenerative diseases such as Parkinson’s and Alzheimers.