A Study to Learn More About How Well Elinzanetant Works and How Safe it is for the Treatment of Vasomotor Symptoms (Hot Flashes) That Are Caused by Hormonal Changes Over 52 Weeks in Women Who Have Been Through the Menopause (OASIS-3)

A Double-blind, Randomized, Placebo-controlled Multicenter Study to Investigate Efficacy and Safety of Elinzanetant for the Treatment of Vasomotor Symptoms Over 52 Weeks in Postmenopausal Women

Researchers are looking for a better way to treat women who have hot flashes after they have been through the menopause. Hot flashes are caused by the hormonal changes that happen when a woman's body has been through the menopause. Menopause is when women stop having a menstrual cycle, also called a period. During the menopause, the ovaries increasingly produce less sex hormones as a result of the natural ageing process and related hormonal adjustments. The decline in hormone production can lead to various symptoms which, in some cases, can have a very adverse effect on a menopausal woman's quality of life.

The study treatment, elinzanetant, was developed to treat symptoms caused by hormonal changes. It works by blocking a protein called neurokinin from sending signals to other parts of the body, which is thought to play a role in starting hot flashes. There are treatments for hot flashes in women who have been through the menopause, but may cause medical problems for some people.

In this study, the researchers will learn how well elinzanetant works compared to a placebo in women who have been through the menopause and have hot flashes. A placebo is a treatment that looks like a medicine but does not have any medicine in it. To compare these study treatments, the participants will record information about their hot flashes in an electronic diary. The researchers will study the number of hot flashes the participants have and how severe they are. They will study the results from before treatment and after 12 weeks of treatment.

The participants in this study will take two capsules of either elinzanetant or the placebo once a day. The participants will take the study treatments for 52 weeks.

During the study, the participants will visit their study site approximately 11 times and perform 2 visits by phone. Each participant will be in the study for approximately 62 weeks.

During the study, the participants will:

• record information about their hot flashes in an electronic diary
• answer questions about their symptoms

The doctors will:

• check the participants' health
• take blood samples
• ask the participants questions about what medicines they are taking and if they are having adverse events An adverse event is any medical problem that a participant has during a study. Doctors keep track of all adverse events that happen in studies, even if they do not think the adverse events might be related to the study treatments.

Study Overview

• Status: Completed
• Conditions: Hot Flashes; Vasomotor Symptoms Associated With Menopause
• Intervention / Treatment: Drug: Elinzanetant (BAY3427080); Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 628
• Phase: Phase 3

Contacts and Locations

Study Locations

• Belgium
  • Bruxelles - Brussel, Belgium, 1000
    • CHU Saint-Pierre/UMC Sint-Pieter
  • Ghent, Belgium, 9000
    • UZ Gent
  • Leuven, Belgium, 3000
    • UZ Leuven Gasthuisberg
  • Liège, Belgium, 4000
    • CHU de Liege | CHR Citadel - Department of Gyneacology and Obstetrics
  • Tienen, Belgium, 3300
    • Femicare vzw | Tienen, BE
• Bulgaria
  • Dupnitsa, Bulgaria, 2600
    • Medical Centre Asklepii OOD | Dupnitsa, Bulgaria
  • Pleven, Bulgaria, 5800
    • Multiprofile Hospital for Active Treatment | Avis Medica - Obstetrics and Gynecology
  • Plovdiv, Bulgaria, 4002
    • Spec.Hospital for obstetrics and gynecology Selena OOD
  • Plovdiv, Bulgaria, 4000
    • Multiprofile Hospital for Active Treatment Plovdiv | Obstetrics and Gynecology
  • Samokov, Bulgaria, 2000
    • Multiprofile Hospital for Active Treatment Samokov | Gynecology Department
  • Sofia, Bulgaria, 1431
    • Diagnostic-Consultative Center Alexandrovska | Sofia, Bulgaria
  • Sofia, Bulgaria, 1233
    • Specialized Hospital for Active Treatment of Oncological Diseases Sofia Region | Oncological Gynecology Department
  • Sofia, Bulgaria, 1330
    • Multiprofile Hospital for Active Treatment for Women's Health Nadezhda | Department of Obstetrics and Gynecology
  • Sofia, Bulgaria, 1606
    • Medical Center Panacea OOD | Sofia, Bulgaria
  • Stara Zagora, Bulgaria, 6000
    • Multiprofile Hospital for Active Treatment Niamed OOD | Department of Obstetrics and Gynecology
  • Varna, Bulgaria, 9000
    • SBAGAL Dr. Dimitar Stamatov | Varna, Bulgaria
• Canada
  • Québec, Canada, G2J 0C4
    • Alpha Recherche Clinique | Lebourgneuf
  • Nova Scotia
    • Halifax, Nova Scotia, Canada, B3K 6R8
      • IWK Health Centre | Department of Obstetrics and Gynaecology
  • Ontario
    • Burlington, Ontario, Canada, L7M 4Y1
      • Manna Research (Burlington North)
    • Nepean, Ontario, Canada, K2J 4A7
      • Manna Research (Ottawa)
    • Ottawa, Ontario, Canada, K1H 7W9
      • Ottawa Hospital-Riverside Campus
    • Scarborough Village, Ontario, Canada, M1P 2T7
      • Viable Clinical Research | Mississauga, Canada
  • Quebec
    • Lévis, Quebec, Canada, G6W 0M5
      • Manna Research (Quebec)
    • Pointe-Claire, Quebec, Canada, H9R 4S3
      • Manna Research (Montreal)
• Denmark
  • Gandrup, Denmark, 9362
    • Sanos Clinic | Gandrup, Denmark
  • Herlev, Denmark, 2730
    • Sanos Clinic | Herlev, Denmark
  • Vejle, Denmark, 7100
    • Sanos Clinic | Syddanmark, Vejle, Denmark
• Finland
  • Helsinki, Finland, 29
    • HUS / Naistenklinikka
  • Joensuu, Finland, 80100
    • Pihlajalinna Lääkärikeskus Oy, Savo-Karjala
  • Kuopio, Finland, 70100
    • Mehilainen | Mehilainen Kuopio
  • Oulu, Finland, 90100
    • Lääkärikeskus Gyneko, Gynaecological Medical Center | Oulu, Finland
  • Tampere, Finland, 33100
    • Terveystalo | Terveystalo Tampere Research Unit
• Poland
  • Bialystok, Poland, 15-224
    • Gabinet Ginekologiczny Janusz Tomaszewski
  • Katowice, Poland, 40-156
    • CLINICAL MEDICAL RESEARCH Sp. z o. o.
  • Katowice, Poland, 40-748
    • Vita Longa Sp. z o.o.
  • Katowice, Poland, 40-611
    • Centrum Medyczne Angelius Provita
  • Szczecin, Poland, 71-500
    • Twoja Przychodnia - Szczecinskie Centrum Medyczne
  • Warsaw, Poland, 02-679
    • Centrum Badawcze Wspolczesnej Terapii
• Spain
  • Barcelona, Spain, 8041
    • Hospital de la Santa Creu i Sant Pau | Gynecology Department
  • Madrid, Spain, 28009
    • Instituto Palacios | Investigation Research Unit - Gynecology department
  • Madrid, Spain, 28040
    • Hospital Clinico San Carlos | Women´s Health Institute
  • Madrid, Spain, 28041
    • Hospital Universitario 12 de Octubre | Department of Obstetrics and Gynecology
  • Seville, Spain, 41013
    • Virgen del Rocio University Hospital | Gynecology Unit
  • Valencia, Spain, 46010
    • Hospital Clinico Universitario | Gynecology and Obstetrics Department
  • Madrid
    • Aravaca, Madrid, Spain, 28023
      • Hospital Universitario La Zarzuela - Ginecologia
• United Kingdom
  • Blackpool, United Kingdom, FY2 0JH
    • MAC Clinical Research | Lancashire - Clinical Research Centre
  • Glasgow, United Kingdom, G4 0SF
    • NHS Greater Glasgow and Clyde | Glasgow Royal Infirmary - Gynaecology
  • Liverpool, United Kingdom, L8 7SS
    • Liverpool Women's NHS Foundation Trust | Liverpool Women's Hospital - Gynaecology
  • London, United Kingdom, W12 0NN
    • Imperial College Healthcare NHS Trust| Queen Charlotte's and Chelsea Hospital - Gynaecology
  • Manchester, United Kingdom, M13 9NQ
    • MAC Clinical Research | Greater Manchester Early Phase - Clinical Research Centre
• United States
  • Alabama
    • Mobile, Alabama, United States, 36608
      • Mobile ObGyn, P.C. | Mobile, AL
  • Arizona
    • Mesa, Arizona, United States, 85206
      • Mesa Obstetricians and Gynecologists | Research Department
  • California
    • Garden Grove, California, United States, 92844
      • National Institute of Clinical Research - Garden Grove
    • Huntington Beach, California, United States, 92647
      • Marvel Clinical Research | Huntington Beach, CA
    • Pomona, California, United States, 91767
      • Empire Clinical Research | Pomona, CA
  • Connecticut
    • New London, Connecticut, United States, 06320
      • Coastal Connecticut Research | New London, CT
  • District of Columbia
    • Washington D.C., District of Columbia, United States, 20036
      • IntimMedicine | Washington, DC
  • Florida
    • Boca Raton, Florida, United States, 33486
      • Boca Midwifery
    • Boynton Beach, Florida, United States, 33435
      • Helix Biomedics LLC | Boynton Beach, FL
    • Jacksonville, Florida, United States, 32207
      • UF Health Women's Specialists - Emerson
    • Palm Harbor, Florida, United States, 34684
      • Suncoast Clinical Research - Palm Harbor
    • Sarasota, Florida, United States, 34239
      • Physician Care Clinical Research LLC | Sarasota, FL
    • Trinity, Florida, United States, 34655
      • Suncoast Clinical Research - New Port Richey
  • Georgia
    • College Park, Georgia, United States, 30349
      • Paramount Research Solutions | College Park Location
  • Indiana
    • Brownsburg, Indiana, United States, 46112
      • Investigators Research Group, Llc
  • Louisiana
    • Metairie, Louisiana, United States, 70001
      • Southern Clinical Research Associates
    • Zachary, Louisiana, United States, 70791
      • Southern Clinical Research, LLC
  • Maryland
    • Baltimore, Maryland, United States, 21287
      • Johns Hopkins Hospital - Gynecology and Obstetrics
  • Montana
    • Great Falls, Montana, United States, 59405
      • Boeson Research | Great Falls, MT
    • Missoula, Montana, United States, 59804
      • Boeson Research | Missoula, MT
  • Nevada
    • Las Vegas, Nevada, United States, 89119
      • AMR - Las Vegas
    • Las Vegas, Nevada, United States, 89113
      • Affiliated Clinical Research, Inc. | Las Vegas, NV
    • North Las Vegas, Nevada, United States, 89030
      • Elite Clinical Network (ECN) | Las Vegas Clinical Trials, LLC
  • North Carolina
    • Raleigh, North Carolina, United States, 27612
      • M3 Wake Research | Raleigh, NC
  • Ohio
    • Columbus, Ohio, United States, 43213
      • ClinOhio Research Services, LLC. | Columbus, OH
    • Englewood, Ohio, United States, 45322
      • HWC Women's Research Center | Englewood, OH
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19114
      • Clinical Research Philadelphia | Philadelphia, PA
  • South Carolina
    • Myrtle Beach, South Carolina, United States, 29572
      • Venus Gynecology, LLC | Myrtle Beach, SC
  • Texas
    • Houston, Texas, United States, 77030
      • Advances in Health, INC. | Houston, TX
    • Houston, Texas, United States, 77054
      • UTHealth Womens Research Program | Memorial City
    • Hurst, Texas, United States, 76054
      • Elligo Health Research | Medical Colleagues of Texas
    • Katy, Texas, United States, 77493
      • Elligo Health Research | Protenium Clinical Research
    • League City, Texas, United States, 77573
      • Maximos Ob/Gyn
  • Virginia
    • Norfolk, Virginia, United States, 23507
      • Eastern Virginia Medical School | OB/GYN Clinical Research Center
    • Norfolk, Virginia, United States, 23502
      • Tidewater Clinical Research - Norfolk
  • Washington
    • Seattle, Washington, United States, 98105
      • Seattle Clinical Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Postmenopausal, defined as:

  1. at least 12 months of spontaneous amenorrhea prior to signing of informed consent, or
  2. at least 6 months of spontaneous amenorrhea prior to signing of informed consent with serum follicle-stimulating hormone (FSH) levels > 40 mIU/mL and a serum estradiol concentration of < 30 pg/mL, or
  3. at least 6 months after hysterectomy at signing of informed consent with serum FSH levels > 40 mIU/mL and a serum estradiol concentration of < 30 pg/mL, or
  4. surgical bilateral oophorectomy with or without hysterectomy at least 6 weeks prior to signing of informed consent.
• Moderate to severe hot flash (HF) associated with the menopause and seeking treatment for this condition.
• Participant has completed Hot Flash Daily Diary (HFDD) for at least 11 days during the two weeks preceding baseline visit and is showing eligibility with respect to previous inclusion criterion during this time period.

Exclusion Criteria:

• Any clinically significant prior or ongoing history of arrhythmias, heart block and QT prolongation either determined through clinical history or on ECG evaluation.
• Any active ongoing condition that could cause difficulty in interpreting vasomotor symptoms (VMS) such as: infection that could cause pyrexia, pheochromocytoma, carcinoid syndrome.
• Current or history (except complete remission for 5 years or more) of any malignancy (except basal and squamous cell skin tumors). Women receiving adjuvant endocrine therapy (e.g. tamoxifen, aromatase inhibitors, GnRH analogues) cannot be enrolled in this study.
• Uncontrolled or treatment-resistant hypertension. Women with mild hypertension can be included in the study if they are medically cleared prior to study participation.

• Untreated hyperthyroidism or hypothyroidism.

  • Treated hyperthyroidism with no abnormal increase of thyroid function laboratory parameters and no relevant clinical signs for > 6 months before signing of informed consent is acceptable.
  • Treated hypothyroidism with normal thyroid function test results during screening and a stable (for ≥ 3 months before signing of informed consent) dose of replacement therapy is acceptable.
• Any unexplained post-menopausal uterine bleeding
• Clinically relevant abnormal findings on mammogram.
• Abnormal liver parameters.
• Disordered proliferative endometrium, endometrial hyperplasia, polyp, or endometrial cancer diagnosed based on endometrial biopsy during screening.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Participants will receive matching placebo orally once daily.	Drug: Placebo; Matching placebo orally once daily.
Experimental: Elinzanetant (BAY3427080); Participants will receive 120 mg elinzanetant orally once daily.	Drug: Elinzanetant (BAY3427080); 120 mg elinzanetant orally once daily

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Change in Frequency of Moderate to Severe Hot Flashes (HFs) From Baseline to Week 12 (Assessed by Hot Flash Daily Diary [HFDD])	The HFDD items assess the number of mild, moderate, and severe HF experienced during the day and during the night. Mild HF are defined as a "sensation of heat without sweating", moderate HF are defined as a "sensation of heat with sweating, but able to continue activity", and severe HF are defined as a "sensation of heat with sweating, causing cessation (stopping) of activity".	Baseline to Week 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Change in Patient-reported Outcomes Measurement Information System Sleep Disturbance Short Form 8b (PROMIS SD SF 8b) Total T-score From Baseline Over Time.	The PROMIS SD SF 8b includes 8 items assessing sleep disturbance over the past 7 days. Items assess sleep quality, sleep depth and restoration associated with sleep, perceived difficulties with getting to sleep or staying asleep and perceptions of the adequacy of and satisfaction with sleep. Participants respond to the items on a 5-point scale from "not at all", "never" or "very poor" to "very much", "always" or "very good". Four of the items are scored reversely. Individual item scores are aggregated to total raw scores which range from 8 to 40. Total raw scores are converted into T-scores for comparison with population norms, with a mean of 50 and standard deviation of 10. T-scores range from 28.9 to 76.5. For both raw and T-scores higher scores indicate greater severity of sleep disturbance. According to available score cut points from PROMIS developers, T-scores can be interpreted as indicating mild (55-59), moderate (60-69), or severe (>70) sleep disturbance.	Baseline to Week 56
Mean Change in Menopause Specific Quality of Life Scale (MENQOL) Total Score From Baseline Over Time	The MENQOL questionnaire is comprised of 29 items assessing the presence of menopausal symptoms and the impact of menopause on health-related quality of life over the past week. The items assess four domains of symptoms and functioning: Vasomotor functioning, psychosocial functioning, physical functioning, and sexual functioning. For each item, the participant indicates if they have experienced the symptom (yes/no). If they select yes, they rate how bothered they were by the symptom using a six-point verbal descriptor scale, with response options ranging from 0 'not at all bothered' to 6 'extremely bothered'. Based on the individual responses, item scores, domain scores, and a total MENQOL score are calculated. Each score ranges from 1-8, higher scores indicate greater bother.	Baseline to Week 56

Collaborators and Investigators

• Sponsor: Bayer

Publications and helpful links

General Publications

• Panay N, Joffe H, Maki PM, Nappi RE, Pinkerton JV, Simon JA, Soares CN, Thurston RC, Francuski M, Caetano C, Genga K, Haberland C, Haseli Mashhadi N, Laapas K, Parke S, Seitz C, Schwarz J, Zuurman L. Elinzanetant for the Treatment of Vasomotor Symptoms Associated With Menopause: A Phase 3 Randomized Clinical Trial. JAMA Intern Med. 2025 Nov 1;185(11):1319-1327. doi: 10.1001/jamainternmed.2025.4421.

Helpful Links

• Click here to find further information and, after study completion, the study results according to Bayer's transparency standards

Study record dates

Study Major Dates

• Study Start (Actual): August 27, 2021
• Primary Completion (Actual): March 29, 2023
• Study Completion (Actual): February 12, 2024

Study Registration Dates

• First Submitted: August 27, 2021
• First Submitted That Met QC Criteria: August 27, 2021
• First Posted (Actual): September 1, 2021

Study Record Updates

• Last Update Posted (Actual): December 1, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Menopause
• Additional Relevant MeSH Terms: Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hot Flashes
• Other Study ID Numbers: 21810; 2021-000059-38 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

IPD Plan Description

Availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA "Principles for responsible clinical trial data sharing". This pertains to scope, timepoint and process of data access. As such, Bayer commits to sharing upon request from qualified researchers patient-level clinical trial data, study-level clinical trial data, and protocols from clinical trials in patients for medicines and indications approved in the US and EU as necessary for conducting legitimate research. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014.

Interested researchers can use www.vivli.org to request access to anonymized patient-level data and supporting documents from clinical studies to conduct research. Information on the Bayer criteria for listing studies and other relevant information is provided in the member section of the portal.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No