TEXAS – A US judge in Texas on Friday suspended the two-decade-old approval of the abortion pill mifepristone while a legal challenge proceeds, dealing another setback to abortion rights in the United States.

Adding to the volatile legal landscape around abortion, a federal judge in Washington state on Friday issued a seemingly conflicting injunction that prevented federal regulators from altering access to the same abortion drug.

The 67-page ruling by US District Judge Matthew Kacsmaryk in Amarillo, Texas, will not take effect for one week, in order to give the Biden administration a chance to file an emergency appeal, which the US Justice Department said it will do.

Judge Kacsmaryk’s ruling is a preliminary injunction that would essentially ban sales of mifepristone while the case by anti-abortion groups before him continues.

The judge, who was appointed to the bench by then President Donald Trump, a Republican, has not yet made a final ruling on the merits of the challenge.

But in his ruling, he found that the lawsuit is substantially likely to succeed. He said the US Food and Drug Administration (FDA) had ignored risks in approving the drug.

“The court does not second-guess FDA’s decision-making lightly,” he wrote. “But here, FDA acquiesced on its legitimate safety concerns – in violation of its statutory duty – based on plainly unsound reasoning and studies that did not support its conclusions.”

The case was brought by four anti-abortion groups headed by the recently formed Alliance for Hippocratic Medicine and four anti-abortion doctors who sued the FDA in November.

They contend the agency used an improper process when it approved mifepristone in 2000 and did not adequately consider the drug’s safety when used by girls under the age of 18 to terminate a pregnancy.

“By illegally approving dangerous chemical abortion drugs, the FDA put women and girls in harm’s way, and it’s high time the agency is held accountable for its reckless actions,” said Mr Erik Baptist of the Alliance Defending Freedom, which filed the case.

President Joe Biden said in a statement released by the White House late on Friday: “The court in this case has substituted its judgment for FDA, the expert agency that approves drugs.

“If this ruling were to stand, then there will be virtually no prescription, approved by the FDA, that would be safe from these kinds of political, ideological attacks.”

‘Extreme anti-choice agenda’

The ruling will likely inflame the fraught US politics of abortion, which have divided the country since 2022’s US Supreme Court ruling that overturned a women’s constitutional right to the procedure.

“Democrats will do everything in our power to fight back to ensure access to safe and legal abortion is protected, and voters will hold every last Republican accountable for an extreme anti-choice agenda,” said Democratic National Committee chairman Jaime Harrison.

Since the Supreme Court ruling, 12 of the country’s 50 states now ban abortion outright, while many others prohibit it after a certain length of pregnancy, according to the Guttmacher Institute, a research organisation that supports abortion rights.

Mifepristone is part of a two-drug regimen, administered in combination with misoprostol, for medication abortions in the first 10 weeks of pregnancy. The drugs account for more than half of all abortions in the US. Some abortion providers have said that if mifepristone is unavailable, they would switch to a misoprostol-only regimen for a medication abortion, which is not as effective. It is not yet clear how widely available it would be.

The Biden administration, responding to the lawsuit, has said the drug’s approval was well supported by science, and that the challenge comes much too late.

While conservative states have banned abortion, others have moved to protect access.

Also on Friday, US District Court Judge Thomas Rice in Spokane, Washington, in a separate lawsuit, issued a preliminary order blocking the FDA from making any changes to the current availability of mifepristone. His ruling applied to the 17 states that sued.

Associate Professor Greer Donley of the University of Pittsburgh’s law school said there was “definitely a direct conflict” between the Texas and Washington orders, which could bring the case before the US Supreme Court more quickly.

The Justice Department had argued that a ruling in favour of the plaintiffs in Texas would undercut trust in the FDA, the agency that signs off on the safety of food products and drugs, and would increase the burden on surgical abortion clinics already overcrowded with women coming from states that now ban the procedure.

US Vice-President Kamala Harris called the ruling a “dangerous precedent”. “This decision undermines the FDA’s ability to approve safe and effective medications... based on science, not politics,” she said in a statement released by the White House late on Friday.

By choosing to sue in Amarillo, the plaintiffs ensured that the case would go before Judge Kacsmaryk, a conservative former Christian activist.

The appeal will go to the New Orleans-based 5th US Circuit Court of Appeals, which has a conservative reputation, with more than two-thirds of its judges appointed by Republican presidents. The next stop after the 5th Circuit would be the US Supreme Court, with its six-three conservative majority.

Mifepristone is available under the brand name Mifeprex and as a generic. Mifeprex maker Danco Laboratories on Friday filed a notice that it would appeal against Judge Kacsmaryk’s decision.

The FDA in January said the government for the first time will allow mifepristone to be dispensed at retail pharmacies. REUTERS