This phase 3 study tested estetrol against a placebo to see if it could help with vasomotor symptoms like hot flashes. The research included 640 women aged 40 to 65 years who had or had not had a hysterectomy. Participants took either 15 mg or 20 mg of estetrol or a placebo for 12 weeks.
The results showed a significant reduction in both the frequency and severity of moderate to severe vasomotor symptoms. At week 4, the 15 mg dose reduced weekly frequency by 9.63 units and the 20 mg dose by 14.94 units. By week 12, reductions were even larger, with the 20 mg dose showing a drop of 22.49 units.
Safety data indicated that adverse events occurred in 51.6% to 57.3% of women taking estetrol, compared to 20.6% on placebo. Serious adverse events were not reported. Discontinuation rates were low, around 6.6% to 7.5% for the drug doses versus 2.3% for placebo. The medication was considered well tolerated. This evidence supports the use of estetrol for managing symptoms in symptomatic postmenopausal women.