Clinical Research Directory

Inclusion Criteria: * Participant has a body mass index ≥ 17 kg/m\^2 and ≤ 38 kg/m\^2 at screening visit. * Participant must be seeking treatment or relief for VMS associated with menopause and confirmed as menopausal, defined as meeting 1 of the following criteria for natural or surgical menopause at the screening visit: * Spontaneous amenorrhea for ≥ 12 consecutive months * Spontaneous amenorrhea for ≥ 6 months with biochemical criteria of menopause (FSH \> 40 IU/L); or * Having had bilateral oophorectomy ≥ 6 weeks prior to the screening visit (with or without hysterectomy). * FSH \> 40 IU/L if participants received hysterectomy but still have an ovary/ovaries. * Within the 10 days prior to start of active treatment, participant must have a minimum average of 7 moderate to severe hot flashs (VMS) per day (data must be available for at least 7 of the last 10 days prior to treatment). * Participant is in good general health as determined on the basis of medical history and general physical examination, performed at the screening visit; hematology and biochemistry parameters, pulse rate and/or blood pressure, and ECG within the reference range for the population studied, or showing no clinically relevant deviations. * Participant has a negative urine pregnancy test at screening; this is not required for participants who have had a total hysterectomy. * Participant has a negative serology panel (i.e., negative hepatitis B surface antigen \[HBsAg\], negative hepatitis C virus antibody \[HCVAb\] and negative human immunodeficiency virus antibody \[HIVAb\] screens) at screening. * Participant agrees not to participate in another interventional study while participating in the present study. Exclusion Criteria: * Participant has known substance abuse or alcohol addiction within 6 months of screening. * Participant has a history of malignancy with the exception of at least 5 years post treatment and without known recurrence. * Participant has a current malignancy, with the exception of non-metastatic basal cell carcinoma of the skin. * Participant has a history within the last 6 months prior to screening of undiagnosed uterine bleeding. * 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) or malignancy that could confound interpretation of the study outcome. * Participant has a history of suicide attempt or suicidal behavior within the last 12 months or has suicidal ideation within the last 12 months, or who is at significant risk to commit suicide. * Participant has previously been enrolled in a clinical trial with fezolinetant or other neurokinin (NK) receptor antagonists. * Participant uses a prohibited therapy (strong and moderate CYP \[cytochrome P450\] 1A2 inhibitors, systemic hormone replacement therapy \[HRT\], or hormonal contraceptive, or any treatment for VMS \[prescription, over the counter, off-label or herbal\]) or is not willing to wash-out and discontinue use of such drugs for the full duration of study conduct. * Participant has received any investigational therapy within 35 days or 5 half-lives, whichever is longer, prior to screening. * Participant has uncontrolled hypertension defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure as ≥ 90 mmHg based on an average of 2 to 3 readings within the screening period. * Participants with a medical history of hypertension who are well controlled may be enrolled. * Participants who do not meet these criteria may be re-assessed after initiation or review of antihypertensive measures. * Participant has active liver disease, jaundice, elevated liver aminotransferases (alanine aminotransferase \[ALT\] or aspartate aminotransferase \[AST\]), elevated total bilirubin (TBL) or direct bilirubin (DBL), elevated international normalized ratio (INR) or elevated alkaline phosphatase (ALP). Patients with mildly elevated ALT or AST up to 1.5 x upper limit of normal (ULN) can be enrolled if TBL are normal. Patients with mildly elevated ALP (up to 1.5 x ULN) can be enrolled if cholestatic liver disease is excluded and no cause other than fatty liver is diagnosed. Patients with Gilbert's syndrome with elevated TBL may be enrolled as long as hemolysis is ruled-out (i.e., DBL, hemoglobin and reticulocytes are normal). * Participant has creatinine \> 1.5 × ULN; or estimated glomerular filtration rate using the Modification of Diet in Renal Disease formula ≤ 30 mL/min per 1.73 m\^2 at screening. * Participant has any condition which makes the participant unsuitable for study participation. * Participant has known or suspected hypersensitivity to fezolinetant or any components of the formulation used. * Participant is unable or unwilling to complete the study procedures.