CNN
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An experimental once-daily pill that does not contain hormones significantly reduced the number of hot flashes in menopausal women and improved their sleep compared to a placebo, according to two new studies conducted by pharmaceutical company Bayer.

The drug, called elinzanetant, works by blocking the brain chemicals responsible for hot flashes and night sweats — what doctors call vasomotor symptoms — in women whose ovaries have slowed production of the hormones estrogen and progesterone. This marks a phase in a woman’s life called menopause, which usually occurs sometime between the ages of 40 and 50.

The U.S. Food and Drug Administration last year approved a similar drug called fezolinetant, which is sold under the name Veozah.

Such medications are new options for women in a phase of their lives when their bodies are adjusting to a new hormonal normal. This transition can bring with it a variety of symptoms, including mood swings, brain fog, libido changes, and insomnia.

Some women find the symptoms bothersome but do not interfere with their daily lives. For others, however, they can be very debilitating and many doctors are reluctant to offer the traditional treatment, hormone replacement therapy, for fear that it could increase the risk of stroke, cancer and heart disease.

“Very few women get any kind of help,” said Dr. Stephanie Faubion, director of the Mayo Clinic Center for Women’s Health.

At the peak of its use in the 1990s, about 40% of postmenopausal women took hormone replacement therapy (HRT), Faubion said. But after a large government study found an increased risk of heart disease and cancer, In connection with the use of hormone replacement therapy in women, the use of hormones for menopausal symptoms fell to around 4%, Faubion said in a commentary on the studies.

Recent studies, including several new analyses of data from the government trial, have shown that hormone replacement therapy (HRT) is not associated with increased health risks for women when used close to menopause and for a limited period of time. Still, many doctors remain skeptical.

In addition, survivors of hormone-sensitive cancers, such as some breast cancers, cannot take hormones to relieve menopausal symptoms. For them, the new non-hormonal drugs are a good alternative, said Faubion, who was not involved in the new trials. But Veozah, the already approved drug, is expensive. Veozah has a list price of $550 per month, and many insurers are unwilling to cover it. Bayer, the company that makes elinzanetent, has not yet said how much it would charge for its drug.

Faubion says she tried to prescribe Veozah for some patients, but their insurance companies required them to try at least two different, less expensive medications before they would reimburse the drug.

“They have to jump through hoops. And I’ve prescribed it before,” Faubion said. She’s not sure if her patients actually took the Veozah. “I don’t know if they actually got the prescription or if they gave up before they got it.”

Both fezolinetant and elinzanetant are among the first drugs to take advantage of a previously unknown signaling pathway in the brain that appears to control hot flashes.

When estrogen levels drop during menopause, nerves in the hypothalamus – a tiny, almond-sized area deep in the brain that helps regulate the body’s thermostat, among other things – become hyperactive, producing an excess of chemical signals called neurokinins. Both new drugs block the entrances to cells where certain neurokinins dock, reducing their ability to stimulate the brain and trigger hot flashes.

“These neurons are super interesting because they are also linked to mood, sleep and appetite. And we know that this is a big part of what happens in women in midlife. They have hot flashes, their mood is terrible, they don’t sleep and they “Weight gain,” Faubion said. It’s not yet clear whether targeting these neurons could help with problems other than hot flashes.

Hot flashes are exactly what they sound like – a sudden feeling of intense heat, usually concentrated in the face, chest and head. It can also cause intense sweating and flushing that may last for several minutes. When this happens at night, it is called night sweats. Women going through menopause may experience this occasionally or several times a day, which can be extremely bothersome.

The approximately 400 women who participated in two related studies published Thursday in JAMA, Symptoms were moderate to severe, which researchers defined as more than 50 hot flashes per week and an average of 14 to 16 per day.

In each trial, researchers gave half of the women the experimental drug, while the other half received a placebo that had no effect. Neither the researchers nor the women knew who was taking the drug or the placebo. The women kept daily diaries to document their symptoms. After 12 weeks, the women who had received the placebo were switched to the study drug and continued taking the drug for another 14 weeks.

After four weeks of taking elinzanetant where women had about eight fewer hot flashes per day – about half the number they reported before the study began, while women taking the placebo reported about four fewer hot flashes per day, a decrease of about a third. The difference was statistically significant, meaning it was probably not due to chance. After 12 weeks, women taking elinzanetant reported having an average of about 10 fewer hot flashes per day, compared with an average change of about seven hot flashes per day in the placebo group. Women taking the drug also reported that their hot flashes were less intense and that they slept better.

At the end of the study, which lasted 26 weeks, more than 80% of women taking elinzanetant had experienced at least a 50% reduction in their hot flashes. The results of both studies were very similar, which gave the researchers confidence in their findings.

The most common side effects in women taking the drug were headache and fatigue.

In a recent press release, Bayer said the company has already submitted its study data to the FDA for approval.

Faubion said it appears to be a very promising drug. How accessible it will be remains to be seen.

“More options for women is a good thing,” Faubion said.