1999 From: Johns Hopkins Medical Institutions
Orphan drug funds to be used in testing new treatment for a rare but deadly form of strokeJohns Hopkins scientists, using funds from a Food and Drug Administration Orphan Drug Award, will test a new way of treating intracerebral hemorrhage with intraventricular extension, a disorder that often hits younger people and African-Americans. In a grant awarded to Johns Hopkins, investigators Neal Naff, assistant professor of neurosurgery, and Daniel Hanley, professor of neurology, neurosurgery and critical care medicine, will lead a group of 12 brain injury centers in a new form of treatment. The $600,000 grant will test the safety and efficacy of using very small doses of tissue plasminogen activator (TPA), a clot-buster, to speed the removal of blood from the middle of the brain. There currently is no treatment for this form of stroke, which has a mortality rate of around 75 percent. TPA is commonly used in cases of heart attacks and many strokes, according to Hanley. It has not been used for intraventricular hemorrhage thrombolysis yet. Orphan drug awards are given by the U.S. Food and Drug Administration to study treatments for uncommon diseases that normally would not attract the attention of profit-driven drug companies. While TPA is not an orphan drug, the treatment is an orphan application, Hanley says. Intracerebral hemorrhage with intraventricular extension strikes about 15,000 to 30,000 people a year. The disorder occurs when the pumping heart pushes the blood through the vessel walls into the tissue in the middle of the brain. Most of the patients are rendered unconscious, Hanley says, and even in the best medical centers, mortality is high. The only treatment is the use of a ventricular drain to remove the blood. In an earlier study, it was shown it takes as long as 10 days to remove all the blood, and the drain itself frequently clogs. The study will test whether with very low doses of TPA, clogging is reduced and the speed blood of extraction is hastened. A normal dose of TPA is 80 to 110 mg in the treatment of stroke. Hanley proposes to use much less, 1 to 3 mg, diluted in the patient's own spinal fluid and injected into the ventricle twice a day. Draining could commence an hour after administration. "We have interesting and very provocative pilot data suggesting that if you get the blood out of the ventricular cavities, the patient's likelihood of mortality is significantly reduced," Hanley says. "We can't investigate everything in one study," he says. "We're investigating whether the drug will work to clear the blood out. If we can demonstrate that, we have the basis to go on to ask whether the clearing of blood actually increases survival rate, whether the blood needs to be cleared out rapidly, or can it be drained slowly." The study begins at the first of the year on 48 patients over a three-year period. "We have some hope we may come to important conclusions before three years," says Hanley. The FDA's Orphan Products Web site is: www.fda.gov/orphan/index.htm
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