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KALAMAZOO GAZETTE, KALAMAZOO, MICHIGAN "A drug co-developed by Pharmacia & Upjohn may, by year's end, be the next medication available to treat Parkinson's disease, a progressive neurological condition marked by shaking, rigidity and slowness of movement. Called Mirapex, the drug is the only one in its class shown to be effective in early stages of the disease. "We are real excited about this drug," said Dr. Mark H. Corrigan, vice president for CNS Development at P&U. "Tests have shown that symptoms of Parkinson's disease are better and stay flat (do not progress) for nine months or more. The drug is well-tolerated." Jointly developed by P&U and Boehringer Ingelheim, Mirapex also has been studied in patients with more advanced disease, Corrigan said. In January, P&U filed a new drug application with the U.S. Food and Drug Administration. Approval could come by year's end. Parkinson's disease, first described by James Parkinson in 1817, is second only to Alzheimer's disease as the most common neurological disorder. It causes significant disability, especially in the elderly. Once diagnosed, symptoms typically worsen over 10 to 15 years. No treatment stops the disease progression, Corrigan said, although a drug called levodopa (L-dopa) can improve symptoms for about a decade. Over time, patients require increasingly larger dosages of levodopa and often suffer undesirable side effects. And since the drug's effective period is limited, doctors delay starting its use as long as possible. "Once you begin taking L-dopa, you start the clock running,"Corrigan said. In people with Parkinson's disease, certain brain cells in the part of the brain called the substantia nigra begin to die. No noe knows why. It may be a hereditary condition in some cases or caused by toxic substances produced in the body or from the environment. These cells produce a brain chemical messenger called dopamine, one of scores of so-called neurotransmitters the brain and other nervous system cells use to "talk" to one another. In this case, the neurons that produce dopamine send appropriate signals to other neurons involved in the motor skills that slowly deteriorate in Parkinson's disease. Corigan said that while levodopa works well for a while, the large dosages needed are like throwing 'buckets of water on someone trying to get a drink." It's now thought that levodopa in such large doses may actually be toxic to neurons, he said. Mirapex is a class of drugs that mimic the action of dopamine and that can be used alone or in conjunction with levodopa, Corrigan said. People in later stages of the disease have been given Mirapex with DuPont Pharmaceuticals' Sinimet, a drug that contains both levodopa and a drug called carbidopa that slows the body's ability to break down levodopa. Mirapex, Corrigan said, allows doctors to use lower doses of Sinimet and still achieve the same therapeutic effect. "Mirapex has been a joy to develop, an absolute joy," Corrigan said. "We have had no negative results. Everyone has had some benefit. In milder cases, the patients are probably normal." This article appeared in today's newspaper. Jim Ryan 56/7