CincinnatióResults of a North American study show that prourokinase, a new thrombolytic (clot buster) agent, is effective in opening blocked cerebral arteries and improving patient recovery after stroke when administered through a small tube placed directly in a brain clot. These findings were announced at the Stroke and Cerebral Circulation Meeting of the American Heart Association in Nashville. Thomas Tomsick, MD, professor of radiology and neurosurgery at the University of Cincinnati (UC) College of Medicine, director of neuroradiology at The University Hospital, and member of the Greater Cincinnati and Northern Kentucky stroke team, participated in the study as clinical technical advisor.
"The study showed that one patient in seven benefitted from the treatment. Patients with great neurologic deficit benefitted more than patients less severely affected. But the impact of recovery on that one patient is immeasurable," says Tomsick. "This study once again emphasizes the importance of rapid identification of stroke signs and symptoms," says Joseph Broderick, MD, professor of neurology at the UC College of Medicine, and member of the Greater Cincinnati and Northern Kentucky stroke team.
"Treatment may have been even more beneficial had the patients in the study been treated earlier," says Tomsick. "Intravenous tPA is useful within three hours, but is less effective opening blockages of the middle cerebral artery. Yet, some patients improve with intravenous clot-busting drugs alone because they can be given without the delay of placing a tube in a brain blood vessel."
Performed in 51 centers across the United States and Canada, the study involved 12,323 patients who were screened for treatment by neurologists and emergency physicians within six hours after the stroke onset. These patients were subsequently examined and treated by neurovascular experts, who placed catheters (small tubes) in the carotid artery and cerebral arteries.
Abbott Laboratories, manufacturer of prourokinase, is expected to apply for approval to the Food and Drug Administration in June, making the drug potentially available for use by January 2000. Prior to approval, treatment of cerebral artery blockage is still possible with other available clot-busting agents that have proven useful in some patients. "Unfortunately, not every patient can be helped. One of four patients in the study died from the effects of the stroke despite treatment," says Tomsick. "The ability to help one patient in seven may not seem like a great benefit considering the major expenditure of time and effort by the treatment team, but it gives hope that more strokes can be treated in the future," says Broderick. "Other developments, such as clot-removal devices, may prove to be even more beneficial, but we must keep people aware that something can be done if they seek immediate care," says Tomsick.