Zuranolone: What to know about the breakthrough postpartum depression treatment just approved by the FDA

Zuranolone, trade name Zurzuvae—a steroid that works to rapidly repair dysregulated neuronal networks in the brain—is only the second drug approved for the condition, thought to affect one in seven women. The other, Zulresso (brexanolone), was approved by the FDA in 2019. But it’s administered via IV over time and requires a hospital admission, making it inaccessible to many women.

Such a barrier doesn’t exist with the newly approved drug, taken at home once daily for two weeks. For many women, one or two courses of the medication over a year will be enough to send them into remission and keep them there, Dr. Kristina Deligiannidis—director of women’s behavioral health at Zucker Hillside Hospital in Queens, N.Y., and lead clinical trial investigator for the drug—told Fortune on Wednesday, ahead of the FDA’s decision.

“Postpartum depression is a serious and potentially life-threatening condition in which women experience sadness, guilt, worthlessness—even, in severe cases, thoughts of harming themselves or their child. And because postpartum depression can disrupt the maternal-infant bond, it can also have consequences for the child’s physical and emotional development,” Dr. Tiffany R. Farchione, director of the Division of Psychiatry in the FDA’s Center for Drug Evaluation and Research, said in a late Friday statement.

“Having access to an oral medication will be a beneficial option for many of these women coping with extreme—and sometimes life-threatening—feelings.”

Improvement in just 3 days

In trials, zuranolone showed a “rapid reduction of depressive symptoms starting as early as day three—after two doses of medicine—and showed continued improvement through day 15,” Deligiannidis said, adding that the drug continues to work even after patients stop taking it, for 45 days in all.

The fast-acting, temporary nature of the drug stands in contrast to standard-of-care antidepressants that might otherwise be prescribed. Such medications—typically SSRIs, or selective serotonin reuptake inhibitors, which increase serotonin levels in the brain—usually take four to six weeks to begin to work, and two to three months to fully kick in, according to Deligiannidis.

Women with postpartum depression are busy sustaining a new life, their own life, and perhaps the lives of other children as well. They can’t wait months for relief, she said: “Especially for women with severe postpartum depression, this could be a life-saving option.”

“It’s like Z-Pak for depression,” Dr. Craig Chepke, medical director of Excel Psychiatric Associates in Huntersville, N.C., and occasional consultant for Zuranolone developer Sage Therapeutics, told Fortune on Wednesday.

He referenced azithromycin, a quick-acting five-day course of pills for bacterial infections like bronchitis and pneumonia often prescribed by general practitioners.

“This is exactly how primary care providers would love to treat depression,” he said of the new drug. “It fits with the model they’re used to. I think they’re going to feel more comfortable, that it’s just like treating a UTI or a sinus infection, and think, ‘I can do that.’”

Because Zuranolone works differently than standard depression treatments, and much more quickly, “it offers a lot of hope for people who haven’t done well in the past,” he added.

No weight gain or reduction in libido, trials show

Clinical trials showed that patients on zuranolone didn’t experience weight gain or reduced sex drive—side effects typical of SSRIs that are often “deal killers” for patients.

Side effects of the new drug may include drowsiness, dizziness, diarrhea, fatigue, the common cold, and urinary tract infections, according to a news release issued Friday by the FDA. But side effects “can’t last longer than two weeks, because you only take it for two weeks,” Chepke noted. “It changes the calculus for a lot of people who would otherwise quit medication.”

Because zuranolone is a controlled substance, the U.S. Drug Enforcement Administration now has 90 days to assign a schedule to it. Earlier this week, Chepke predicted it would be designated a Schedule IV drug, or one with a low potential for abuse and dependence like Xanax, Valium, Ativan, and Ambien.

From there, he anticipated it would soon be in the hands of prescribers and patients, where it’s sorely needed.

Depression is still widely thought of as a nuisance condition in which “you get down from time to time, but your pick yourself up by the bootstraps,” he said. “Even in churches, there’s the notion of ‘too blessed to be stressed.’ It’s as if it’s not a big deal. But it is a big deal. And we need better treatment options to help.”

On Wednesday, Deligiannidis was hopeful word of the FDA’s approval would come before the end of the work week, and with it, a wave of press that encourages new mothers to seek the help they deserve—for their sake, and for their sake of their children.

“Depression can increase the risk for poor birth outcomes,” and such negative outcomes can continue after a child is born, she said.

“For mom’s sake, for baby’s sake, for the family’s sake, we want women to discuss their symptoms with a trusted healthcare provider ASAP.”

Drug not yet approved for major depressive disorder

Sage Therapeutics had also applied for approval to use the drug in cases of major depressive disorder. The federal agency on Friday did not issue a ruling on such use.

In 2021, an estimated 8% of American adults—21 million—had at least one major depressive episode, according to the U.S. National Institutes of Health. If approved for major depressive disorder as well, the drug could shift the paradigm on depression from a chronic condition that requires lifelong medication to an acute illness that, for many, necessitates just a short course of drugs during flares, experts told Fortune.