Cell-based therapy shows promise in patients with Parkinson's disease

Apr 28, 2008

A novel cell therapy using retinal pigment epithelial (RPE) cells attached to tiny gelatin bead microcarriers implanted in the brain can improve the symptoms of patients with moderate to advanced Parkinson’s disease (PD).

Rush University Medical Center neurosurgeon Dr. Roy A. E. Bakay and colleagues from Emory University, Atlanta found the therapy Spheramine was well-tolerated and patients experienced improvement in Parkinsonian symptoms (tremor, rigidity, slowness of movements, and impaired balance and coordination.) These findings were presented at the Annual Meeting of the American Association of Neurological Surgeons in Chicago on April 28, 2008.

The pilot study was initiated at Emory University Hospital and followed six patients with moderate to advanced PD to investigate the safety, tolerability, and efficacy of the Spheramine implantation. The full patient group has been evaluated for four years, and several have been monitored for six years. Bakay and colleagues report long-term improvement or stabilization of symptoms, maintained for a minimum of two years after Spheramine implantation. They note no Spheramine-related serious adverse events were reported and that the most frequent adverse event was postsurgical headache, which spontaneously resolved within one to two weeks.

“The results of this study are very encouraging – Spheramine is well tolerated through several years of follow-up and improvement in parkinsonian symptoms is sustained,” stated Bakay.

The cellular product Spheramine consists of RPE cells attached to microcarriers. RPE cells produce levodopa, the precursor of dopamine. Dopamine is a neurotransmitter produced by nerve cells in the brain that progressively declines as the disease progresses.

The RPE cells, which are normally found in the back of the eye, are cultured under standardized conditions and attached to the microscopic beads prior to implantation. The microcarriers are necessary for the cells to survive in the brain. The implanted cells serve as a new potential source of levodopa to enhance dopamine production where it is most needed.

The patients were selected based on disease stage, levodopa responsiveness, and severity of PD symptoms while off medication. An even distribution of Spheramine was surgically implanted into the more affected side of the brain, and patients left the hospital a few days later.

The primary efficacy measure in this trial is the motor score of the Unified Parkinson’s Disease Rating Scale (UPDRS) when the patient has been OFF antiparkinsonian medication for at least 12 hours. The researchers report clinical improvements were noted in both UPDRS motor scores off medication (44 percent improvement from baseline at 48 months) and patient-reported quality of life scores (23 percent improvement from baseline of total PDQ-39 score at 48 months). Several of these patients have been monitored for 6 years and the trial has been extended to 10 years of follow-up.”

Bakay said positive results in the pilot study prompted the initiation of a Phase IIb, multicenter, double-blind, randomized, sham surgery-controlled study (STEPS) to further evaluate the safety, tolerability and efficacy of Spheramine. Changes from the pilot study included implantation in both sides of the brain and the addition of a sham surgery group. To date, 71 patients have been randomized for either Spheramine or sham surgery and results from the will become available later this year.

Parkinson’s Disease

Parkinson’s disease is a progressive brain disorder that affects a person’s motor skills which worsen as the disease advances. 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.

PD affects one in every 100 people over the age of 65. 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 an estimated 19,500 PD-related deaths in the United States in 2005, an increase of 1,500 deaths from 2004.

It is estimated to cost $23 billion a year in direct and indirect costs and lost productivity. Despite therapeutic advancements, oral medications provide insufficient symptom control after the disease has progressed and new approaches are needed.

Source: Rush University Medical Center

Explore further: Study shows Tamiflu gets patients back on their feet faster, reduces flu complications

add to favorites email to friend print save as pdf

Related Stories

The latest fashion: Graphene edges can be tailor-made

5 hours ago

Theoretical physicists at Rice University are living on the edge as they study the astounding properties of graphene. In a new study, they figure out how researchers can fracture graphene nanoribbons to get ...

Infrared imaging technique operates at high temperatures

5 hours ago

From aerial surveillance to cancer detection, mid-wavelength infrared (MWIR) radiation has a wide range of applications. And as the uses for high-sensitivity, high-resolution imaging continue to expand, MWIR sources are becoming ...

Recommended for you

Kidney-brain connection may help drive chronic kidney disease

8 hours ago

In addition to affecting blood pressure, high-salt intake can promote kidney function decline in patients with chronic kidney disease. A study appearing in an upcoming issue of the Journal of the American Society of Nephrology (J ...

Flu's grip on U.S. starting to weaken: CDC

8 hours ago

(HealthDay)—After a rough start to the flu season, the number of infections seems to have peaked and is even starting to decline in many parts of the nation, federal health officials reported Thursday.

Litchi fruit suspected in mystery illness in India

8 hours ago

A mysterious and sometimes fatal brain disease that has afflicted children in northeastern India for years could be linked to a toxic substance in litchi fruits, US researchers said Thursday.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.