Suit Challenges Firm’s Patent on AIDS Drug : Pharmaceuticals: The expensive treatment AZT is the only approved therapy that attacks the virus directly.

A lawsuit announced Tuesday challenges Burroughs Wellcome Co.’s patent on the anti-AIDS drug AZT and seeks to have it invalidated so other companies could market the drug at cheaper prices.

The suit, filed in federal court here, claims that the company did not conceive, develop or demonstrate the use of the drug in AIDS therapy, and failed to identify federal scientists as the true developers in its patent application.

Burroughs Wellcome disputed the allegations. “The idea that our company would engage in illegal activities to obtain patent rights is both offensive and wrong. We fully expect to prevail in the lawsuit,” said company President Philip R. Tracy.

If Burroughs Wellcome were stripped of its patent, it would lose its exclusive rights to produce, distribute and sell AZT as a therapy against the AIDS virus.

“Even though AZT is the only treatment option for thousands of people with AIDS, there are countless numbers of people who simply cannot afford it and must do without, or who must spend their last dollars . . . to purchase AZT at an outrageously inflated price,” said Derek Hodel, executive director of the People with AIDS Health Group.

The suit was filed on behalf of the New York-based AIDS health group, which helps import drugs for personal use of AIDS patients, and two Washington men who are infected with the AIDS virus and are using AZT.

Public Citizen, a nonprofit, public interest group founded by consumer activist Ralph Nader, filed the lawsuit and is representing those named in the suit.

AZT was approved by the Food and Drug Administration in 1987. It is the only approved therapy that attacks the AIDS virus directly, slowing progression of the disease.

The drug is labeled for use by people who have AIDS--acquired immune deficiency syndrome--and for those who are infected with the human immunodeficiency virus, or HIV, that causes the disease but who have not yet developed symptoms.

Worldwide sales of AZT were $287 million last year, including $175 million in the United States, company spokeswoman Kathy Bartlett said.

The wholesale price for AZT is about $2,200 per year for the typical dose regimen for someone HIV-infected with no symptoms and about $2,800 per year for those with symptoms, she said.

After pharmacy and other markups, the cost of the drug is around $3,000 per year for a typical dosage, Hodel said. That could be cut in half if competing sources were allowed to market the drug, he said.

The drug is a synthetic compound that was invented in 1964 by a Michigan Cancer Foundation scientist under a federal grant, the lawsuit said. It was determined to be highly toxic and of no use at the time. After AIDS was discovered in the early 1980s, researchers became interested in the drug.

The suit claims that government scientists at the National Cancer Institute and researchers at Duke University played the key roles in developing AZT therapy for AIDS, but that Burroughs Wellcome failed to mention this when it applied for a patent for the drug.

“The public paid for the development of the drug, and now the public is paying for its sale through programs like Medicaid and in higher insurance costs,” said Brian Wolfman, a Public Citizen staff attorney.

“This lawsuit will establish the public’s right to a fair price, and it gives the government a vehicle to challenge Burroughs Wellcome’s monopoly,” he said.

Burroughs Wellcome, however, said in a statement that its scientists were the first to conceive of use of AZT as an AIDS treatment and that this was the basis of its patent.