Word: tpa
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While such therapies remain theoretical, reducing stickiness is already proving useful in heart disease, specifically in combatting a dangerous side effect of clot-busting drugs like streptokinase or TPA. Doctors have found that after such drugs are used, lingering pieces of broken-up clots (consisting mainly of platelets) look to surveillance cells like a flood of damaged tissue. Instantly, the inflammation process kicks in: the affected region of the heart becomes sticky and therefore prone to further clotting. Adhesion research has produced a drug now being tested on heart patients that keeps the scattering clot fragments from sticking...
Then why were U.S. doctors so quick to adopt the medication? For one thing, cost is still not a primary concern for many U.S. doctors. In Canada and Europe, where cost constraints and rationing of health care are a matter of course, TPA did not enjoy great success; streptokinase plus ordinary, cheap aspirin remain the standard anticlotting therapy. In addition, pervasive fears of malpractice suits in the U.S. add to the pressures on doctors to use the latest technique...
...biggest reason TPA took off was the aggressive promotional campaign launched by its manufacturer, Genentech. The worldwide market for anticlotting agents, or thrombolytics, is estimated at $600 million a year. To get a substantial piece of the action, Genentech relentlessly promoted its product not just to doctors and patients but to researchers as well. "I have never seen anything like it," said Dr. Charles Hennekens, U.S. coordinator for the study released last week...
Genentech, Hennekens says, refused to participate in the international study, which compared TPA with streptokinase and a third thrombolytic called anistreplase, so a British-made version of TPA was used instead. Moreover, Hennekens says, when he tried to recruit doctors to participate, he found that some had been told by Genentech salesmen that using the other drugs in the trial could endanger their patients. Streptokinase, they were told, could cause cerebral bleeding, and anistreplase, which is derived from human plasma, was alleged to carry a risk of AIDS infection. Neither danger is significant, said Hennekens. Genentech denied any direct meddling...
...Though TPA is a dramatic example, many heavily promoted new drugs offer only subtle advantages over cheaper alternatives. Dr. Sidney Wolfe, an outspoken consumer advocate in Washington, says that 70% to 90% of newly approved drugs are not important therapeutic advances. One example: substances called lower osmolarity contrast mediums, introduced in 1986. Used in taking diagnostic pictures of internal organs, they are believed to be only marginally safer than existing agents but are sold at up to 12 times the price...