FDA career scientists raised red flags about the drug’s safety and efficacy, even as the agency and the White House are under pressure to expand contraceptive options in a highly charged political environment around access to abortion, which has dramatically shrunk since the Supreme Court overturned Roe v. Wade last year. FDA approval would be a major step forward for the decades-long campaign to have the U.S. join dozens of other countries where hormonal contraceptives are available without a prescription.

“The FDA has been put in a very difficult position of trying to determine whether it is likely that women will use this product safely and effectively in the nonprescription setting,” said Karen Murry, deputy director of the FDA’s office of nonprescription drugs. FDA staff don’t vote at advisory committee meetings.

“When a development program is proposed for a nonprescription drug, we can’t just approve it based on the experience in the prescription setting without the applicant doing adequate studies,” she added.

Ahead of the meeting, HRA Pharma conducted a clinical trial to assess whether consumers could identify if they should take the pill, and if so, could they correctly take it at around the same time every day. The trial initially included more than 1,700 participants and ultimately followed 883 participants who logged electronically when they took the pills.

HRA Pharma concluded that most consumers, including adolescents and people with limited health literacy, would take the pill as instructed or use alternative contraception if they didn’t.

But FDA scientists had concerns over HRA’s data, including that patient-reported diaries are often unreliable. Many study participants, for example, reported taking more pills than were available. HRA Pharma attributed this to likely user error, while FDA scientists said it could be a sign of serious misuse of the pill.

“I can’t think of a study that has 30 percent invalid data … it’s really very extraordinary,” said Theresa Michele, the director of the FDA’s office of nonprescription drugs.

Arthur Stone, professor of psychology, economics and public policy at the University of Southern California who presented on behalf of HRA Pharma, said the over-reporting had to do with the study’s design. The study’s e-diary did not prompt users to log daily whether they took a pill and allowed users to back-fill data for several days, possibly resulting in participants overstating the number of pills taken.

The agency also said that there was a risk that people with contraindications, such as a history of breast cancer or unexplained vaginal bleeding, might take the pill, or that adolescents or people with low health literacy would try to use the pill as an emergency contraception.

Ultimately, the advisers disagreed and concluded that the benefits of the pill outweighed the risks — particularly given that health care providers know patients often don’t precisely follow instructions on prescription drugs.

“If [consumers] don’t use it appropriately, the safety profile is such that there is very little to no risk,” said Leslie Walker-Harding, a pediatrician and chief academic officer and senior vice president of Seattle Children’s Hospital who voted on the recommendation.

Abbey Berenson, a professor of obstetrics, gynecology and pediatrics at the University of Texas Medical Branch who also voted, argued that typical use of hormonal birth control isn’t perfect, even when patients get the pill from health care providers. “It is very difficult for people to long-term take birth control pills … at the same time every day.”

In FDA presentations to the experts, agency scientists also pointed out that Opill was approved for prescription use in the early 1970s, which may not reflect current populations nor the current standards used to approve drugs.

Advisers did not agree. “The standards for approving Opill would be different today, yes, but that is true for many drugs — including other oral contraceptives,” said Suzanne Robotti, president of the MedShadow Foundation and a voting consumer representative.

Jack Resneck, president of the American Medical Association who did not attend the meeting, told POLITICO he was “very, very pleased” with the advisory committees’ unanimous vote.

“These are medications that we know are safe and effective from decades of use by millions of women in countries around the world,” he said. “There’s a particularly acute need for this right now in the post-Dobbs era, as the consequences of unintended pregnancies are even more substantial than they had been before.”

What’s next: The committees’ recommendation is not binding, though the FDA often follows what the experts conclude. The FDA is expected to decide whether Opill should be over the counter this summer.

Alice Miranda Ollstein contributed to this report.