Ultra-low dose estradiol and dydrogesterone for the treatment of menopausal symptoms in a pooled, multi-ethnic population

•Estradiol 0.5 mg/dydrogesterone 2.5 mg reduced menopausal vasomotor symptoms.•This ultra-low dose was associated with fewer hot flushes per day (vs placebo).•Women receiving the ultra-low-dose estradiol/dydrogesterone reported improved health-related quality of life.•Combined estradiol 0.5 mg/dydrogesterone 2.5 mg was well tolerated at this dosage.•The efficacy of this ultra-low dose was consistent across a multi-ethnic population. Evidence suggests ethnicity-specific differences in postmenopausal symptoms, highlighting the need for therapies that are efficacious across different ethnicities. We evaluated the efficacy of an ultra-low dose combination of 0.5 mg estradiol and 0.25 mg dydrogesterone (E 0.5 mg/D 2.5 mg) in alleviating vasomotor symptoms across a multi-ethnic population. Data from two controlled trials were pooled to form a dataset of 583 postmenopausal women from across Europe and China. Participants were randomized to receive treatment with E 0.5 mg/D 2.5 mg or placebo for 12 weeks. The main efficacy variable was absolute change in the number of hot flushes from baseline to end of treatment. Health-related quality of life and safety were also assessed. Change in the number of hot flushes per day was greater with E 0.5 mg/D 2.5 mg versus placebo (mean difference − 1.5, 95 % confidence interval − 2.1, −1.0; p