Thursday, 28 August 2008
Telmisartan: Stroke drugs show similar results, or no benefits
Two studies released call into question the advantage of using a blood pressure medicine and a well-known blood thinner for preventing the recurrence of a stroke.
The first found that patients who received the blood pressure drug telmisartan were no less likely to have another stroke than those taking a placebo.
In the second study, doctors discovered that clopidogrel, which limits clotting, was no better than aspirin combined with the anti-platelet drug dipyridamole for reducing the chance of stroke. Clopidogrel is sold by Bristol-Myers Squibb under the brand name Plavix while Boehringer Ingelheim GmbH makes dipyridamole under the brand name Persantine.
Both papers, released online by the New England Journal of Medicine, come from the "Profess" study, which included 20,332 patients from 695 medical centers in 35 countries.
Strokes kill about 5 million people worldwide each year and having high blood pressure increases the risk. When a person survives a stroke, there is an 8 percent chance of having another within one year.
That is why telmisartan, sold by various brand names such Boehringer Ingelheim's Micardis or the Pritor or Kinzal brands by Bayer Schering Pharma, was given to half the volunteers in the study, led by Salim Yusuf of McMaster University on Ontario, Canada.
After two and a half years of followup, 8.7 percent had another stroke compared to 9.2 percent in the placebo group, an insignificant difference.
The drug, an angiotensin-receptor blocker, also had no effect on the risk of heart attack, other major cardiovascular events or diabetes, the study, paid for by provately held Boehringer Ingelheim, showed.
Among volunteers receiving Plavix as their blood thinner, 8.8 percent had another stroke versus 9 percent for the aspirin-dipyridamole combination. The risk of major bleeding was similar in both groups.
"Furthermore, there was no significant difference between the two treatments in the risk of fatal or disabling strokes," said the authors, led by Ralph Sacco of the Miller School of Medicine at the University of Miami.