What this trial studies
Hot flashes are the most common reason women going through menopause seek medical attention. Hormone replacement therapy, or HRT, is most often prescribed to treat hot flashes. However, HRT can't be used by all women or for as long as may be needed. Researchers want to find other ways to treat hot flashes.
Conditions in scope
- Hot Flashes
Interventions
- Fezolinetant (Drug) — oral
- Placebo (Drug) — oral
Who can join
Women only · Ages 40 Years to 65 Years
Inclusion criteria
- Participant confirmed as menopausal per one of the following criteria at the screening visit (visit 1):
- Spontaneous amenorrhea for \>/=12 consecutive months;
- Spontaneous amenorrhea for \>/=6 months with biochemical criteria of menopause (follicle-stimulating hormone (FSH) \> 40 IU/L);
- Having had bilateral oophorectomy \>/=6 weeks prior to the screening visit (visit 1) (with or without hysterectomy); or
- Having had hysterectomy without bilateral oophorectomy with the biochemical criteria of menopause (FSH \> 40 IU/L).
- Participant must be seeking treatment or relief for vasomotor symptoms (VMS) associated with menopause and meet some set criteria related to hot flash(es) (HFs) (VMS) prior to randomization.
- Participant agrees not to participate in another interventional study while participating in the present study.
Exclusion criteria
- Participant has a history of an undiagnosed uterine bleeding within the 6 months prior to the screening visit (visit 1).
- Participant has a current malignant tumor or history (except for a participant who has not received treatment for malignant tumors for at least 5 years before informed consent acquisition and was not considered to have recurrence) of a malignant tumor except for non-metastatic basal cell carcinoma of the skin.
- Participant has a medical condition or chronic disease (including history of neurological \[including cognitive\], hepatic, renal, cardiovascular, gastrointestinal, pulmonary \[e.g., moderate asthma\], endocrine, or gynecological disease) that could confound interpretation of the study outcome.
- Participant uses a prohibited therapy (hormone therapy, hormone replacement therapy (HRT), hormonal contraceptive, any treatment for menopausal symptoms \[prescription medications, over-the-counter, or herbal/Kampo medicines\] or strong or moderate cytochrome P450 1A2 (CYP1A2) inhibitors) and is not willing to wash out or discontinue use of such drugs from screening visit (visit 1) through the follow-up visit (visit 6) or it is not medically appropriate to discontinue such drugs for the duration of the study.
- Participant has been randomized/registered in a clinical study with fezolinetant previously or had previous exposure to marketed fezolinetant elsewhere.
- Participant has a present or previous history of participation in this study.
- Participant has received any investigational therapy within 28 days or 5 half-lives, whichever is longer, prior to screening (visit 1).
- Participant has an unacceptable result from the transvaginal ultrasound (TVU) assessment at screening (i.e., full length of endometrial cavity cannot be visualized or presence of clinically significant abnormal findings).
Eligibility wording paraphrased from the public record. View the full criteria on ClinicalTrials.gov before contacting a site.
Where it’s happening
| City | State / Region | Facility | Site status |
|---|---|---|---|
| Chita-gun | Aichi-ken | Chita Kosei Hospital | Unknown |
| Kōnan | Aichi-ken | Konan Kosei Hospital | Unknown |
| Nagoya | Aichi-ken | Daido Clinic | Unknown |
| Nagoya | Aichi-ken | MEITETSU Hospital | Unknown |
| Toyota-shi | Aichi-ken | Toyota Kosei Hospital | Unknown |
| Chiba | Chiba | Chiba Aoba Municipal Hospital | Unknown |
| Funabashi-shi | Chiba | Aiiku Ladies Clinic | Unknown |
| Kashiwa-shi | Chiba | Tsujinaka Hospital Kashiwanoha | Unknown |
| Matsudo-shi | Chiba | Juno Vesta Clinic hatta | Unknown |
| Fukuoka | Fukuoka | Fukuoka Mirai Hospital | Unknown |
Showing the first 10 of 64 sites. See all sites on ClinicalTrials.gov.
Status & timeline
- Overall status: Completed
- Study type: Interventional
- Phase: PHASE3
- Start date: 2024-02-16
- Primary completion: 2025-10-22
- Last update posted: 2025-12-23
- First posted: 2024-01-16
Sponsor & contact
Lead sponsor: Astellas Pharma Inc (Industry)
For trial site contact information, use the official record at ClinicalTrials.gov. Contact details change frequently and the public record is the source of truth.
Outcome measures
Primary outcomes
- Mean change from baseline in the frequency of mild to severe vasomotor symptoms (VMS) (Baseline and Week 8)
Frequency of mild, moderate or severe VMS events will be calculated as the sum of mild, moderate or severe VMS events per day.
Related ClearedRx care
If you’re reading this trial because you have menopause symptoms now, you don’t have to wait for a trial to access evidence-based care. ClearedRx prescribes the same FDA-approved and compounded HRT products that have been studied in trials like this one for decades.
Important. Information from ClinicalTrials.gov as of May 8, 2026. Trial details (status, sites, contacts, eligibility, outcomes) change frequently — always check the official record at https://clinicaltrials.gov/study/NCT06206408 before contacting a site.
ClearedRx is not affiliated with this trial or its sponsor. We index public-domain ClinicalTrials.gov records to help patients find evidence-based context for menopause care decisions. ClearedRx itself is a telehealth menopause/HRT brand — we do not enroll patients in trials.