Proponents say the pill, which has been used by millions of women in 13 countries, could transform abortion in the United States by making it more accessible and more private. But it can be used only in the earliest days of pregnancy.
The pill, also called mifepristone, causes an abortion by preventing a fertilized egg from attaching itself to the uterus. It is for use in women who are up to 49 days pregnant. RU-486 would be manufactured and distributed by Danco Laboratories LLC, a small New York-based company.
It would probably be available by November, people close to the approval negotiations said.
RU-486 is expected to reshape reproductive health in the United States, transforming the abortion process from an invasive procedure to a one as simple as swallowing a few pills. About 1 million women have surgical abortions each year.
"The approval of mifepristone is the result of the FDA's careful evaluation of the scientific evidence related to the safe and effective use of this drug," said Dr. Jane Henney, commissioner of food and drugs. "The FDA's review and approval of this drug has adhered strictly to our legal mandate and mission as a science-based public health regulatory agency."
"Mifepristone, or the early-abortion pill, is as significant a technological advance for women's health as the birth-control pill was 40 years ago," said Gloria Feldt, president of Planned Parenthood Inc. "It will enable them, if they choose to terminate a pregnancy, to do that earlier (and) to do it without surgery. For many women, that is a very positive thing."
The drug has been in the approval process for almost a decade. It has been available in France since 1988 and has since become commonplace in much of Western Europe, China and Israel.
The U.S. version of the pill, however, would be subject to regulations unusual for standard prescription drugs, sources said. It could be prescribed only by doctors who perform abortions, rather than, as is usual, by any physician. In addition, the prescribing doctor will be required to have admitting privileges at a hospital within one hour of his or her office.
RU-486 would also contain a ``black box'' warning, sources said, a stern caution reserved for powerful drugs like thalidomide, which is known to cause birth defects, and the narcotics that are used to ease cancer patients' pain.
Danco was in frantic negotiations with the FDA over the past few weeks, even as late as Wednesday night, to complete its plans to package and distribute the pill.
With the presidential race in full swing, the drug's approval could become an explosive issue. Vice President Al Gore has said he would not block its distribution. Gov. George W. Bush of Texas has said he is opposed to it. Anti-abortion activists have said they will file a lawsuit blocking its distribution if RU-486 is approved.
Approval had been expected in February but was postponed after the FDA released a statement saying that certain questions ``need to be resolved before final manufacturing approval can be granted.'' A deadline of Sept. 30 was set for a final decision.
The pill has been vehemently opposed by anti-abortion groups, whose protests have contributed to the drug's lengthy approval process.
The French company that makes the pill, Roussel-Uclaf, refused to sell it in the United States, fearing boycotts and violence. No U.S. pharmaceutical would touch it either.
Roussel-Uclaf handed the rights to RU-486 to the Population Council, a New York-based nonprofit international abortion rights group. The council funded clinical trials on women in the United States and gathered studies showing that almost half a million women in Europe have taken it safely. The studies do show that it has some side effects, including bleeding, cramping, nausea and diarrhea.
The Population Council sought FDA approval in March 1996. The agency ruled that it was safe and effective, but it had questions about how it would be marketed and distributed, and concerns related to the heated political atmosphere surrounding abortion and abortion clinics.
At the time, the Population Council had difficulties securing a manufacturing partner. Eventually, it struck up a partnership with Danco, a somewhat secretive company run by a former executive of the drug giant Merck & Co. Danco would sell RU-486 directly to abortion doctors and clinics.
RU-486 induces abortion by blocking receptors of the hormone progesterone, which plays an important role in developing a fetus. Another drug, misoprostol, is then taken to cause contractions, in which the fetus is expelled.
RU-486 would be administered in a doctor's office, then misoprostol would be taken at home. Studies have shown this combination to have been effective 95 percent of the time in producing early abortions.