Skin Patch For Parkinson's Disease Proves Effective in Large Study
August 03, 2001
The first large-scale study of a skin patch to treat Parkinson's disease shows that a patch under development seems to be as effective as traditional oral medications in treating the disease. The findings were presented this week in Helsinki at the International Conference on Parkinson's Disease, sponsored by the World Federation of Neurology.
"Patients have access to skin patches for heart disease, for smoking cessation, for motion sickness, and for pain control. We believe this is the first time that a neurodegenerative disorder has been treated with a patch," says Karl Kieburtz, M.D., professor of neurology at the University of Rochester Medical Center and one of the lead investigators of the study.
"Many groups are exploring new ways of delivering Parkinson's drugs, and this is the first to show success in a large study," says Kieburtz. "There's an active worldwide effort to deliver medicines in new ways besides by mouth, especially since the digestive tract of patients with Parkinson's is affected by the disease."
The study of 242 patients at 36 sites around North America involved a medication known as rotigotine, which is still experimental and is not available to patients. Rotigotine is being developed by Schwarz Pharma of Germany together with Discovery Therapeutics Inc. The study was funded by Schwarz.
When compared to patients who received a placebo, patients in the study who received the medication improved an average of 20 to 30 percent on a scale that measures how the disease affects their daily lives: how well they walk and talk, how flexible their arms and legs are, how steady they can hold their hands, and other motor skills. Participants were in the early stages of the disease; most had been diagnosed within 18 months of the study.
The silicone patch used in the study carries a dopamine agonist, a type of drug commonly used to treat the disease. The symptoms of Parkinson's, including tremors and stiff and slow movements, are caused by the death of brain cells that produce dopamine, a brain chemical that's key to controlling movement. Dopamine agonists mimic dopamine and stimulate brain cells like the natural chemical.
Each participant in the study wore four skin patches that were replaced once each day. Doctors followed patients' progress for about three months, noting an improvement in motor skills and tracking side effects. Altogether nearly half the patients who received the medication complained of nausea, about 40 percent had some skin reaction, and a few felt fatigue or sleepiness. In most patients the skin reaction went away on its own, and the frequency of the other side effects is similar to current dopamine agonists used to treat the disease, Kieburtz points out.
The study was conducted by the Parkinson Study Group (PSG), an independent group of investigators at 81 academic institutions around North America led by physicians at the University of Rochester Medical Center. Ira Shoulson, M.D., of the University of Rochester heads the Parkinson Study Group and was the principal investigator of the current study; Karen Blindauer, M.D., of the Medical College of Wisconsin was co-principal investigator. The results in Helsinki were presented by Stanley Fahn, M.D., of Columbia University, who is co-chair of the PSG.
At Rochester the study was coordinated through the Department of Neurology's Clinical Trials Coordination Center and the Division of Experimental Therapeutics, where physicians are trained to design and interpret studies of potential new treatments to neurodegenerative diseases such as Parkinson's and Huntington's diseases.