WASHINGTON - Gov. George W. Bush, who promises to make prescription drugs more affordable, signed legislation making it more difficult for Texas doctors to prescribe a cheaper generic version of a popular blood-thinning drug.
The legislation was sought by DuPont Merck Pharmaceutical, the drug giant that manufactures the name-brand drug and tried to persuade states to block the new, generic competition. Just three states, including Texas, adopted laws.
Texas has since reversed course, now agreeing with the Food and Drug Administration that generic warfarin is just as safe and effective as name-brand Coumadin. A spokesman for Bush defended the law, saying the governor was protecting patients when he signed the legislation in 1997.
''When we're talking about drugs that have the potential of life or death, we ought to have an extra safety measure for patients,'' said Dan Bartlett, spokesman for the Republican presidential nominee.
Many health experts say that risk was greatly exaggerated.
''It's pretty clear the FDA has gone to extensive lengths to verify the quality and standards necessary for generic drugs,'' said one heart specialist, Dr. Raymond Woosley, chairman of pharmacology department at Georgetown University School of Medicine.
And one of Bush's own top health advisers argues that it should be up to doctors and patients - not state drug boards - to choose among FDA-approved drugs.
''Generics offer lower cost alternatives in most cases. They ought to be used as an option,'' Gail Wilensky, who helped craft Bush's Medicare prescription drug plan, said Tuesday.
Vice President Al Gore's presidential campaign is seizing the issue as it alleges that Bush is a pawn of industry.
''This is another case of Governor Bush siding with powerful special interests and against the interests of middle class families,'' Gore spokesman Doug Hattaway said.
The controversy surrounds Coumadin, a blood thinner taken by some 2 million people, mostly heart disease sufferers, to prevent blood clots. DuPont had been the exclusive manufacturer of the drug for decades, although its patent expired in 1962.
In 1996, the FDA approved a generic substitute, known as warfarin, concluding that it is identical to Coumadin and safe and effective for patients to use.
DuPont mounted a campaign to convince state legislatures that the two are not the same. Coumadin is part of a class of pharmaceuticals known as ''narrow therapeutic index'' drugs. That means the dosages must be tightly controlled. Slightly too little, and the medicine is ineffective; slightly too much, and it can be toxic.
The generic, DuPont told legislators, may not get the dosage just right. Barr Laboratories, manufacturer of the generic version, made the opposite case in a lobbying campaign of its own.
Overwhelmed with questions, in 1998 the FDA took the unusual step of writing a letter to doctors and state pharmacy boards stressing its conclusion that the generic warfarin is just as good as Coumadin.
DuPont was motivated partly by profit and partly by concern for patients, argued Stuart Haines, an expert on drug therapy at the University of Maryland who gets some of his research money from DuPont.
''Clearly they wanted to protect their market share,'' he said. ''It may have been the primary motive. It may have been secondary.''
A dollar's worth of Coumadin costs DuPont less than 10 cents to make, and the generic version is sold for 40 to 50 percent less than the name brand.
Haines said he understands why doctors might be cautious about using a new generic drug, but he doesn't think states should intervene if a drug has been approved by the FDA. ''They should have relied on the judgment of pharmacists and physicians,'' he said.
More than 20 states considered legislation. Of the three that adopted laws, just one of them - in North Carolina - is in effect. Legislation adopted in Virginia was never implemented.
In Texas, the legislation directed the pharmacy board to draw up a list of drugs that would be subject to the law, which required pharmacists to double check with doctors who prescribed them. The board adopted a list of nine drugs including Coumadin, by far the most popular among them.
Barr labs sued the board on procedural grounds, saying it had not issued its regulations properly. The board lost the case and reissued the rules in 1999. But after public hearings it concluded that opponents of the legislation were right and there was no reason to require extra scrutiny, said Gay Dodson, the board's executive director.
Together, Coumadin and its generic version sell some $540 million per year. Three years ago, DuPont had nearly 99 percent of the market. The generic version now has 20 percent.