The anti-blood clot regimen that adds the drug clopidogrel (Plavix) to aspirin treatment is unlikely to prevent recurrent strokes and may actually increase the risk of bleeding and death in patients with subcortical stroke, according to late-breaking research presented at the American Stroke Association’s International Stroke Conference in 2012.
The new study is raising more concerns about the safety and effectiveness of Plavix, the blockbuster blood-thinner sold by Sanofi Aventis.
The Plavix-aspirin combination is approved to prevent future heart attacks, strokes and other cardiovascular events in people with acute coronary syndrome. The Plavix-aspirin arm of the Secondary Prevention of Small Subcortical Strokes Trial (SPS3) was trying to determine if that combination could also prevent recurrences in people who had suffered a subcortical stroke. This type of stroke occurs when blood vessels deep in the middle of the brain are blocked, damaging small areas of brain tissue. People who suffer subcortical strokes are predisposed to dementia.
In August 2011, the anti-clotting portion of SPS3 study was halted because of preliminary findings that subcortical stroke victims treated with the Plavix-aspirin combo had an unexpectedly high rate of serious bleeding events and death. According to a press release issued by the American Heart Association, the anti-clotting arm of the SPC3 study involved 3,020 patients at 81 sites in the USA, Canada, Spain, Mexico and South America who were assigned the Plavix-aspirin combo or aspirin plus placebo within 180 days of suffering symptoms of a subcortical stroke.
According to the study’s preliminary findings, patients receiving aspirin plus placebo had a 1.1% of bleeding risk per year. Meanwhile, the aspirin plus Plavix group experienced a 2.1% bleeding risk per year. The bleeding events reported largely stemmed from major bleeds somewhere other than in the brain.
At the same time, aspirin plus placebo had a 1.4% risk of death, while aspirin plus clopidogrel had a 2.1 percent risk of death. There was no difference in stroke recurrence in both treatment arms, the press release said.
There was no difference in stroke recurrence in both treatment arms.
“These interim results do not support the use of combination clopidogrel plus aspirin for secondary stroke prevention in patients with small subcortical strokes,” the study’s authors said.
American Heart Association/American Stroke Association guidelines for preventing recurrent strokes recommend anti-clotting medications like aspirin, the customary treatment, or other clot preventing therapies Plavix, but not the combination of the two.
The Plavix prescribing label already notes that its use with aspirin in people with recent stroke has been linked to increased risk of bleeding. It further states that Plavix-aspirin therapy does not offer any additional benefit over Plavix alone in people with recent stroke.
In the United States, stroke is the No. 4 killer and a leading cause of disability among adults. And, each year, about 185,000 stroke patients have a recurrent attack.
