A sign on an insurance store advertises Obamacare in San Ysidro
A sign on an insurance store advertises Obamacare in San Ysidro, San Diego, California, U.S., October 26, 2017. Reuters

A federal judge in Texas on Thursday blocked Obamacare's mandate that health insurance plans cover preventive care, including screenings for cancer, diabetes and depression and pre-exposure prophylaxis against HIV (PrEP) at no cost to patients.

U.S. District Judge Reed O'Connor in Fort Worth, Texas, previously found that the PrEP mandate violated a federal religious freedom law and that other no-cost preventive care mandates were based on recommendations by an illegally appointed task force.

The judge has now blocked the federal government from enforcing the mandates, a victory for conservative businesses and individuals that sued to challenge them in 2020.

The U.S. Department of Health and Human Services (HHS), which administers the Affordable Care Act (ACA), as Obamacare is formally called, did not immediately respond to a request for comment.

More than 150 million people were eligible for preventive care free of charge as of 2020 under the ACA, according to data from HHS. If O'Connor's ruling is not paused or overturned on appeal, insurers will be able to charge patients copays and deductibles for such services.

Lisa Lacasse, president of the American Cancer Society Cancer Action Network, said that could have "huge implications" and make it more difficult to catch treatable cancers early.

"We cannot emphasize enough how important screenings are for early detection of cancer," she said.

"Allowing personal or political bias to interfere with the practice of medicine will cause harm to our patients," the American College of Obstetricians and Gynecologists said in a statement. "No-copay coverage of critical preventive care like HIV prevention is intended to increase access in order to keep people healthier."

The legal challenge was brought by eight individuals and two businesses, all from Texas. They argued that the free PrEP requirement requires business owners and consumers to pay for services that "encourage homosexual behavior, prostitution, sexual promiscuity and intravenous drug use" despite their religious beliefs.

They also said that the advisory body that recommends what preventive care should be covered without cost, the Preventive Services Task Force, is illegal because its members are not directly appointed by the president, which they argue is required by the U.S. Constitution.

The task force's recommendations, which also include screening for health risks like preeclampsia in pregnant women and for sexually transmitted infections, automatically become mandatory under the Affordable Care Act.

The conservative America First Legal Foundation is helping to represent the plaintiffs. The group was founded by Stephen Miller, who served as an adviser to Republican President Donald Trump.

O'Connor previously drew attention in 2018 for ruling the entire Affordable Care Act, the signature achievement of Democratic then-President Barack Obama, was unconstitutional in a decision that was later overturned.

The PrEP drugs approved in the United States to prevent HIV infection, which can cause AIDS, are made by Gilead Sciences Inc and by ViiV Healthcare, a joint venture of GSK Plc, Pfizer Inc and Shionogi & Co Ltd. The companies did not immediately comment.