Do combinations of 1 mg estradiol and low doses of NETA effectively control menopausal symptoms?

This study compared two continuous-combined hormone replacement therapy (HRT) formulations, 1 mg estradiol (E2)/0.25 mg norethisterone acetate (NETA) and 1 mg E2/0.5 mg NETA, with placebo, with regard to the efficacy for vasomotor symptom relief in menopausal women.

A total of 119 women aged 45-61 years with moderate and severe hot flushes and with amenorrhea for at least 3 months were randomly assigned to 12 weeks' treatment with 1 mg E2/0.25 mg NETA, 1 mg E2/0.5 mg NETA or placebo. The number and severity of hot flushes, as well as any vaginal bleeding, were recorded on a daily basis. The Kupperman Menopausal Index, Greene Climacteric Scale and visual analog scales for various symptoms were assessed before and after treatment. Subpopulation analysis according to menopausal status was performed.

Both combinations significantly reduced the number and severity of hot flushes, compared to placebo. A reduction of approximately 85% in vasomotor symptomatology occurred in the two combination groups by week 4 of treatment, and this was further diminished throughout the study to approximately 97% reduction by week 12. At the end of the study, 85% of the women receiving 1 mg E2/0.5 mg NETA and 71% of the women receiving 1 mg E2/0.25 mg NETA were considered to the clinically adequate responders to treatment. Both combinations were associated with significant improvements, compared to placebo, in visual analog scales for overall general condition, Kupperman Menopausal Index, and Greene Climacteric vasomotor and psychological subscales. While both combinations resulted in similar bleeding profiles in postmenopausal women, the combination of 1 mg E2/0.5 mg NETA resulted in the lowest incidence of bleeding in late perimenopausal women.

The combinations of 1 mg E2/0.25 mg NETA and 1 mg E2/0.5 mg NETA rapidly relieve vasomotor symptoms and are efficacious in the majority of menopausal women, including those with severe hot flushes.