Jump to content
Dr. Okun

Update on Neurturin Gene Therapy from Ask the Doc

Recommended Posts

We would like the members of our forum to be up to date on new and exciting therapies and discoveries in Parkinson disease. Here is an article from the internet on neurturin, a growth factor that may be delivered to the brain using gene therapy technology. Studies are promising and trials in PD are underway.


Novel Gene Therapy Treatment For Parkinson's Disease Shows Promise


Main Category: Parkinson's Disease News

Article Date: 22 Apr 2007 - 0:00 PDT


It is estimated that 60,000 new cases of Parkinson's disease (PD) are diagnosed each year, adding to the estimated one to 1.5 million Americans who currently have the disease. The latest epidemiology studies indicate that worldwide numbers will increase from an estimated 4.1 million in 2005 to 8.7 million people with PD by 2030. There were nearly 18,000 PD-related deaths in the United States in 2004. While the condition usually develops after the age of 55, the disease may affect people in their 30s and 40s.


Early in the disease, there is a loss of brain cells that produce the chemical dopamine. Normally, dopamine operates in a delicate balance with other neurotransmitters to help coordinate the millions of nerve and muscle cells involved in movement. Without enough dopamine, this balance is disrupted, resulting in tremor (trembling in the hands, arms, legs and jaw); rigidity (stiffness of the limbs); slowness of movement; and impaired balance and coordination the hallmark symptoms of PD.


In the last 10 years, protein substances called "growth factors" have been discovered that can slow or halt the death of dopamine-producing cells. One such factor, known as "GDNF" (Glia-Derived Neurotrophic Factor), has been used in clinical trials for PD. The results have been inconsistent, possibly related to the method of delivering the protein to the brain.


Researchers at the University of California at San Francisco, and Rush-Presbyterian Medical Center in Chicago, in conjunction with Ceregene, Inc. of San Diego, Calif., recently undertook a Phase I trial using a novel strategy called "gene transfer" to deliver a growth factor to the brains of 12 patients with PD. All patients entered in the trial were judged to have inadequate control of their disease with standard levadopa therapy and would have otherwise been potential candidates for treatment interventions such as deep brain stimulation (DBS).


The results of this study, Intrastriatal Gene Transfer with AAV-Neurturin for Parkinson's Disease: Results of a Phase I Trial, will be presented by Philip A. Starr, MD, PhD, 11:45 am to 12:00 p.m. on Monday, April 16, 2007, during the 75th Annual Meeting of the American Association of Neurological Surgeons in Washington, D.C. Co-authors are Leo Verhagen, MD, Paul S. Larson, MD, Roy Bakay, MD, Robin Taylor, RN, Deborah Cahn-Weiner, PhD, Raymond Bartus, MD, Jill L. Ostrem, MD, and William J. Marks Jr., MD.


The growth factor gene was delivered as part of a modified virus, or "viral vector", called adeno-associated virus (AAV). This viral vector helps enable the gene to be delivered into the correct brain cells, but has been modified so that it cannot reproduce or damage brain cells. The growth factor gene neurturin was utilized, which is a protein closely related to GDNF. Neurturin has been shown in laboratory studies to help prolong survival of dopamine-making cells. AAV-neurturin was delivered directly to the brain via stereotactic injection through multiple (16) needle injections into the striatum, the part of the brain most deficient in dopamine. This was performed through small openings in the skull.


The patients were studied using standard rating scales of movement in PD, the Unified Parkinson's Disease Rating Scale (UPDRS) prior to surgery and on a continual basis post surgery, at baseline, 1, 3, 6, 9 and 12 months, on and off medication. Two different doses of the viral vector were tested, the lower dose in the first six patients, and the higher dose in the remaining six patients. The following outcomes were noted:


-- There were no major adverse effects from this treatment at the low or high doses.


-- In nine of the 12 patients for which one-year outcome data was available, the improvement in the UPDRS was 38 percent.


"Patients with PD urgently need therapeutic approaches that not only improve their symptoms and daily functions, but positively modify the underlying components of the disease, stated Dr. Starr.


"Existing therapies for PD treat only the symptoms, and are effective for a limited period of time, so any trial that is safe and results in promising efficacy data is worth pursuing. The safety data and preliminary efficacy data that resulted from this Phase 1 study are encouraging, and clearly warrant the need for a larger, Phase II study," concluded Dr. Starr.


Founded in 1931 as the Harvey Cushing Society, the American Association of Neurological Surgeons (AANS) is a scientific and educational association with more than 6,800 members worldwide. The AANS is dedicated to advancing the specialty of neurological surgery in order to provide the highest quality of neurosurgical care to the public. All active members of the AANS are certified by the American Board of Neurological Surgery, the Royal College of Physicians and Surgeons (Neurosurgery) of Canada or the Mexican Council of Neurological Surgery, AC. Neurological surgery is the medical specialty concerned with the prevention, diagnosis, treatment and rehabilitation of disorders that affect the entire nervous system, including the spinal column, spinal cord, brain and peripheral nerves.


American Association of Neurological Surgeons (AANS)

5550 Meadowbrook Dr.

Rolling Meadows, IL 60008

United States


Share this post

Link to post
Share on other sites

Thought I would copy this to this surgical thread...hope this is okay. These are my words from the Ask The Parkinson Dietician board.


Posted May 3rd/Written May 2nd in the middle of another sleepless night...ugh!:

I am considering this trial for myself, and I am attending a Q&A with the Investigator, and two other patients, tomorrow...oops today!


I have asked several in the PD community about the sham surgery component of this trial. Some are a long way from considering DBS, some already have DBS, and some who were waiting for DBS. The reactions have been varied, and only one has jumped for joy. She would volunteer herself, but is only 3 yrs post dx.


Most of the reactions have been, why would I have someone drill holes in my head and then do nothing! Of course, my thought to that comment is do we want a promising therapy to get to the surgeons treatment shelf, or do you want it to just sit in limbo and never get to a point that the community can appreciate what life it may give back to us. If a total of 51 people, following in the footsteps of the 12 in Phase I, don't step to the plate...limbo is where CERE-120 is going to be.


Think about what we have been through in the years we have dealt with PD, respectively, and then think of those yet to be diagnosed. Do we want to have them suffer the way we have all suffered.


How do you feel about sham surgery?


When I told my oldest daughter about the sham surgery, at first she was appalled that I would even consider the trial. But, as I explained to her about CERE-120 being the most promising therapy next to a cure, which is lightyears away, if ever, she began to come around, especially when I reminded her about my other option. The other option being DBS with all its hardware and being turned on and having tune-ups and battery replacements over time (for lack of a better description at the moment).


If I don't enter the CERE-120 trial, or get disqualified for some reason, I will have early intervention DBS (PD for 17 years now).


PD takes and keeps on taking. I don't want to give anymore away!!


Update - Written May 6th - Replying to another trail participate in the Ask The Parkinson Dietician board

Thanks for the words of encouragement. Great to hear that your husband is doing so well. You both deserve a round of applause for your courage. This is definitely not the usual "take a pill" trial, in which I have also participated in the past.


I have made my final decision and feel great about the decision. Yes, I have read the Consent form and nothing surprising there either...but goodness so much poking and proding! As a member of a large project that tracks evolving therapies as the come through the industry pipeline, I have have watched this therapy evolve and watched with anticipation. I have posted a great deal of reading material in another much larger forum...NeuroTalk.


I sent my "It's a go!" email to the Philadelphia coordinator on Friday, and I am now calendared to go for the consent review and the initial evaluation a week from now. We will see if I can physically qualify for the trial. If not, then it is early DBS for me, as my tremor is becoming grossly problematic.

Share this post

Link to post
Share on other sites

Sham surgery seems at first glance a bad idea, however it is an important aspect of proving a therapy. In the transplant trials the sham group may have ultimately been in a better position. They got to look at the results before proceeding and they did not get the runaway dyskinesias seen from transplant.


Proving a therapy for the masses requires rigor, and it has become necessary in many cases to have a sham arm of the trial. If you are uncomfortable then I would consider DBS or another therapy. It is ok to be uncomfortable. Studies are designed to allow the patient the choice!

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now