Bayer’s hot flash drug posts promising results while awaiting FDA nod
Bayer’s drug candidate to ease menopausal hot flashes was deemed safe and effective for long-term use in study results released this week as the German pharma giant awaits delayed approval by U.S. regulators. Photo by RDNE Stock project/Pexels
German pharma giant Bayer this week published the full results of a major clinical study demonstrating the long-term safety and efficacy of its hot flash drug elinzanetant as it awaits delayed approval decisions by U.S. regulators.
The Phase 3 study’s findings, released Monday in JAMA Internal Medicine, found that elinzanetant met goals set for effectiveness in relieving moderate-to-severe “vasomotor symptoms,” or VMS, such as hot flashes and sleep disruptions over a period of 52 weeks — doubling the timeline established in earlier studies.
The researchers also found the drug was safe after participants took it for a year, bolstering widespread hopes that, once it is approved by the Food and Drug Administration, elinzanetant could be a blockbuster drug in the United States and a “game-changer” for women who want or need an alternative to estrogen replacement therapy to combat VMS.
Bayer touts it as the first such drug that targets both the neurokinin-1 and 3 (NK-1 and 3) receptors in the hypothalamus region of the brain. They are estrogen-sensitive neurons that react to a decrease of the hormone, such as during menopause, by becoming enlarged and disrupting the body’s heat control mechanisms, thus triggering episodes of VMS.
The company has already gained approvals in Britain and Canada, where the drug is marketed as under the brand name Lynkuet, and Bayer is betting it can grab a hefty share of the estimated $8.6 billion global menopausal hot flashes market from rival Veozah, made by Japan’s Astellas, which gained FDA. approval two years ago and is being extensively marketed in television ads and elsewhere.
Elinzanetant’s path to the U.S. market, however, was hit by delays in July when Bayer announced the expected FDA review of its New Drug Application had been pushed back three months to late October.
The company said the delay was not related to concerns about the drug’s efficacy or safety, triggering speculation that extensive staffing cuts at the agency under the Trump administration are slowing down the new drug approval process.
This week’s results from the “OASIS 3” clinical trial officially confirmed guidance issued by Bayer last year in which the pharma giant touted continued “positive results” regarding both the efficacy and safety of elinzanetant, building on similar outcomes from the earlier OASIS 1 and 2 studies.
The company pointedly noted that no incidences of liver damage were observed — that finding comes months after the FDA issued its most serious “black-box warning” to competitor Veozah due to rare but potentially severe liver risks.
OASIS 3 study co-author Richard Anderson, a professor of clinical reproductive science at the University of Edinburgh in Scotland, said the latest results are good news for women who are seeking non-hormonal relief from their VMS symptoms.
“While hormone treatment is effective in controlling menopausal symptoms for many women, many cannot or do not want to take hormones,” he told UPI.
“A safe and effective alternate would be of great value, and the emerging data on elinzanetant suggest that it may be just that: highly effective, and acting very quickly to help with these often debilitating symptoms. So far, the data on safety also look reassuring.”
The authors reported that among a group of 628 women with a mean age 54.7 years, those taking the drug daily saw a nearly 80% reduction in the frequency of moderate-to-severe episodes of VMS compared to those taking a placebo — comparable to the effectiveness of estrogen therapy.
Importantly, participants in the treatment arm also reported fewer sleep disturbances and improved quality-of-life scores, which is what separates elinzanetant from fezolinetant, the active ingredient used in Veozah, according to OASIS 3 co-author Dr. JoAnn Pinkerton, the Mamie A. Jessup Professor of Obstetrics and Gynecology at the University of Virginia.
“We really think that this product does differentiate itself from fezolinetant in potentially providing additional improvements in sleep and quality of life-mood issues,” Pinkerton told UPI.
“As a physician, I see many untreated women whose hot flashes are disruptive, and if they’re severe, they can disrupt their daily lives and affect their work productivity and relationships. We really need treatment options that are effective, but many of the non-hormonal options we’ve had to date are just not that effective.
“What I think is really exciting is that elinzanetant, if it’s approved, is going to provide another option for these women, and it can be a first-line treatment for those with moderate-to-severe hot flashes due to menopause,” added Pinkerton, who is also the emeritus executive director and past president of The Menopause Society.
The unmet need for more non-hormonal options to treat hot flashes is clear, agreed Dr. Stephanie Trentacoste McNally, a gynecologist at Long Island Jewish Medical Center in New York and an associate professor at Hofstra University’s Zucker School of Medicine.
McNally, who was not connected with the OASIS 3 study, noted that VMS affects more than 85% of women during their menopausal transition, and that these changes can affect daily living for several years after the final menstrual period, particularly for women who have moderate-to-severe cases.
“Currently, the FDA has approved only two non-hormonal medication for vasomotor symptoms,” she told UPI. “With the introduction of elinzanetant, it would provide another alternative medication for women experiencing these symptoms — particularly for women who cannot take hormonal therapy.”
Moreover, she added, the drug’s unique ability to target both neurokinin-1 and neuorkinin-3 receptors “may provide additional benefits,” as well as providing enhanced safety.
“In this randomized, placebo-controlled study, not only were there statistically significant reduction in symptoms, this dual antagonist medication was not associated with hepatotoxicity, endometrial hyperplasia or significant changes in bone density, suggesting a more favorable long-term safety profile than other medications,” McNally said.
Another expert gynecologist, Dr. Susan Loeb-Zeitlin, director of Women’s Midlife Center at Weill Cornell Medicine and New York-Presbyterian Hospital, also voiced optimism about the potential of elinzanetant in the wake of the study results.
“Hormone therapy is the mainstay treatment for menopausal hot flashes, but there are many people for whom the use of hormones is contraindicated. such as women with breast cancer, heart disease, history of stroke, and other medical conditions,” she said.
“Since menopause is receiving so much attention right now, women are seeking ways to treat their symptoms.”
Fezolinetant has been an effective alternative for the treatment of hot flashes, “but there was case of liver toxicity noted in a patient who received the medication. Elizanetant has not been shown to cause hepatotoxicity. It also has been shown to improve sleep,” she added.
Astellas, meanwhile, reported in April that its 2024 fiscal year sales of Veozah were $230 million, which came up short of expectations, but projected FY 2025 sales to rise to $340 million amid continued U.S. television advertising pushes.
Astellas Chief Commercial and Medical Affairs Officer Claus Zieler told analysts in a July 30 earnings call that he “welcomes” the entry of Bayer with another NK antagonist drug.
“It’s not exactly the same target that their molecule has versus the NK3 that we target very, very specifically,” he said, adding, “We know that that market is very large. We also know that that market takes time to develop. With two companies communicating and educating in this marketplace, I think this market will grow more quickly than if one company does it alone.
“You have to see, in my mind, the entry of Bayer both as a competition to our position with Veozah, but also as a benefit for the development of the market as a whole,” Zieler said.