November 11, 1994
Media Contact:Gary Stephenson
Phone: (410) 955-5384
Researchers at Johns Hopkins report that an experimental drug greatly reduces
the formation of deadly blood clots in women at risk for heart attacks and
"We believe the drug Integrelin increases the efficiency of traditional medicines in patients with unstable angina," said Pascal Goldschmidt-Clermont, M.D., director of the Johns Hopkins Thrombosis Center." When we gave it in addition to standard therapies, clot formation dropped by 75 percent." The study results are scheduled to be presented at the American Heart Association's 67th Scientific Session on November 17.
According to Goldschmidt-Clermont, Integrelin mimics the action of a small segment of fibrinogen, the molecule that clumps blood platelets. Integrelin wiggles its way onto the platelet's surface, taking up residence and blocking fibrinogen access. Without a fibrinogen bond, platelets can't cluster or produce clots that cause heart attacks and strokes.
"Control of unstable angina in women may become easier with new compounds like Integrelin," says Goldschmidt-Clermont. "The next step is to study long-term safety under all conditions." Integrelin is currently available only through study protocols.
In the study, both men and women with unstable angina were randomized into two groups. Each group received standard treatment that included heparin, a blood thinner. One group also got Integrelin injections while the other group received aspirin. Blood samples were taken and patients were monitored repeatedly over 24 hours.
Researchers found that platelet clumping was six times less likely to occur in women on Integrelin. Men, too, experienced a reduction in platelet clumping, although the effect of the drug compared with aspirin was less pronounced.
"We don't understand why it had a different biologic response in women," says Goldschmidt- Clermont. "Only further research in a large patient population will help us explain the gender bias."
In addition, the signs of unstable angina were less pronounced in women on Integrelin. They experienced ischemic (lack of blood flow to the heart muscle) five times less often and their episodes lasted one-fifth of the time compared with women on traditional drug therapy alone (heparin plus aspirin).
Unstable angina is marked by sudden chest pain or tightening that can occur even without exertion or exercise--and often mark the onset of a heart attack. The pain occurs when platelets group together, block arteries and decrease blood flow to the heart, says Goldschmidt-Clermont.
The study was funded by Cor Therapeutics. Other researchers include Steven P. Schulman, M.D., director of the clinical trial; Paul F. Bray, M.D.; Nisha Chandra, M.D.; Pariah Khan, Dmitriy Grigoryev, Patricia Gottdiener, Michael M. Kitt, M.D., Cor Therapeutics and Gary Gerstenblith, M.D.