Dose-Finding Safety and Efficacy Trial of Org50081 (Esmirtazapine) in the Treatment of Vasomotor Symptoms (46101/P06459/MK-8265-012)

Inclusion Criteria: * postmenopausal women, defined as: * 12 months of spontaneous amenorrhea; * OR 6 months of spontaneous amenorrhea with serum Follicle Stimulating Hormone (FSH) levels \>40 mIU/mL; * OR 6 weeks post surgical bilateral oophorectomy with or without hysterectomy. * In case the menopausal status of a subject was unclear because of a hysterectomy, the serum FSH level had to be \>40 mIU/mL. If the date of the last menstruation was not clear because of perimenopausal hormone use, then the subject had to have a serum FSH level \>40 mIU/mL after completion of a washout period (see exclusion criteria below); be \>= 40 and \<= 65 years of age; * have a body mass index (BMI) \>= 18 and \<= 32 kg/m\^2; * minimum of 7 moderate to severe hot flushes per day or 50 per week, as quantified from daily diary recordings during at least 7 days preceding randomization to trial medication; * able to handle the electronic diary device after training and having at least 80% compliance on complete daily diary entries during the period prior to randomization; * give voluntary written Informed Consent (IC) after the scope and nature of the investigation had been explained, before screening evaluations. Exclusion Criteria: * history or presence of any malignancy, except non-melanoma skin cancers * any clinically unstable or uncontrolled renal, hepatic, endocrine, respiratory, hematological, neurological, cardiovascular, or cerebrovascular disease that would put the subject at saf…