E4Relief (Response to Estetrol in Life Improvement for MEnopausal-associated Hot Flushes)

Inclusion Criteria: * Women presenting at least 7 moderate to severe hot flushes/day or at least 50 moderate to severe hot flushes/week in the week preceding randomization. * Body Mass Index (BMI) between 18.0 and 35.0 kg/m², inclusive. * Post-menopausal status. * Intact uterus. * Negative pregnancy test. * Good physical and mental health. * Subject has provided signed and dated written informed consent before admission to the study. * Subject is able to understand and comply with the protocol requirements, instructions, and protocol-stated restrictions. Exclusion Criteria: * Uterine disease or any medical conditions associated with an increase in endometrial thickness. * Any history of malignancy with the exception of basal cell (excluded if within the prior 2 years) or squamous cell (excluded if within the prior one year) carcinoma of the skin. Any clinically significant findings at the breast examination and/or on mammography suspicious of breast malignancy that would require additional clinical testing to rule out breast cancer. * Abnormal cervical Pap smear. * Systolic blood pressure (BP) outside the range 90 to 140 mmHg, diastolic BP outside the range 60 to 90 mmHg, and/or heart rate outside the range 40 to 100 bpm. * Any clinically significant abnormality identified on the screening 12-lead ECG. * History of venous or arterial thromboembolic disease, history of known coagulopathy or abnormal coagulation factors. * Diabetes mellitus with poor glycaemic control. * Dyslipoproteinaemia at screening. * Smoking \>10 cigarettes/day. * Presence or history of gallbladder disease, unless cholecystectomy has been performed. * Systemic lupus erythematosus. * Multiple sclerosis. * Acute or chronic liver disease. * Acute or chronic renal impairment. * Uncontrolled thyroid disorders. * Use of oestrogen or progestin containing drug(s). * Use of non-hormonal treatments to reduce hot flushes. * History or presence of allergy or intolerance to any component of the investigational product. * History of alcohol or substance abuse or dependence in the 12 months before screening as determined by the Investigator. * Sponsor, CRO or Investigator's site personnel or their relatives directly affiliated with this study. * Subjects with known or suspected history of a clinically significant systemic diseases, unstable medical disorders, life-threatening disease or current malignancies that would pose a risk to the subject in the opinion of the Investigator. * Participation in another investigational drug clinical study within 1 month (30 days) or have received an investigational drug within the last 3 months (90 days) prior to study entry. * Is judged by the Investigator to be unsuitable for any reason.