Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: MONDAY, March 4, 1991 TAG: 9103040212
SECTION: NATIONAL/INTERNATIONAL PAGE: A/6 EDITION: EVENING
SOURCE: Associated Press
DATELINE: ATLANTA LENGTH: Medium
Preliminary findings showed that all save lives up to 12 hours after a heart attack and should be given to many more patients than are now receiving them, the study's director, Dr. Rory Collins of Oxford University, said Sunday.
Compared were streptokinase, a 30-year-old drug, and two newcomers: TPA, a genetically engineered drug, and APSAC, a chemically modified version of streptokinase.
The makers of TPA and APSAC have been touting their drugs as an improvement over streptokinase, based on several smaller studies. A dose of streptokinase costs about $200; TPA costs $2,200 per dose and APSAC sells for $1,700.
The results confirm and amplify the findings of a large-scale Italian study and should help end a high-stakes dispute over which clot dissolver is best, Collins said at the annual meeting of the American College of Cardiology.
"In terms of mortality, there is no difference," he said.
The key finding, he said, is that giving clot-dissolving drugs after a heart attack "works, and it works in a much wider range of patients than doctors thought."
That includes those over 75 and those who can't be treated until as long as 12 hours after the heart attack begins, he said.
"The reason for the emphasis on which is better - it's about money," he said.
The study of some 40,000 patients from nearly 1,000 hospitals in the United States and around the world is the largest and most definitive study yet on the effectiveness of the drugs, Collins said.
Collins and his colleagues recorded 1,397 deaths among 13,295 heart attack victims given streptokinase. Among 13,290 patients given the experimental TPA, there were 1,368 deaths. And for APSAC, there were 1,407 deaths among 13,328 patients.
Those figures are virtually identical, showing no significant difference between the three drugs, Collins said.
Streptokinase was also less likely than the other drugs to cause strokes, a consequence of druginduced bleeding in the brain, Collins said.
"Not only was there no mortality gain" with TPA, "it's actually less safe," he said.
In the United States, about 150,000 American heart attack victims are receiving the clot-dissolvers each year, representing about one-fourth of the victims who survive long enough to reach an emergency room, he said.
Genentech, which sells TPA in the United States, said the new trial still does not resolve the question of whether TPA is better than its cheaper rivals.
Dr. David Stump of Genentech said the TPA used in the trial is slightly different from Genentech's, and it wasn't given with an intravenous dose of the anticoagulant heparin, which he said increases TPA's effectiveness.
The bottom line is "you just don't know" whether Genentech's TPA is any better than streptokinase or APSAC, Stump said.
A Genentech-sponsored study to be completed next year will provide what Stump believes is the definitive answer to the question of which drug is best.
TPA is the most widely used clot-dissolver in the United States, while streptokinase is more widely used in Europe, Collins said.
Sales of TPA generated $210 million for Genentech last year, about half the company's total revenue, said Susan Rogers, a spokeswoman.
by CNB