Efficacy of continuous sequential transdermal estradiol and norethindrone acetate in relieving vasomotor symptoms associated with menopause.

Objective: This study was undertaken to evaluate the efficacy and tolerability of a combination estradiol plus norethindrone acetate transdermal delivery system given in a continuous sequential regimen with transdermal estradiol versus placebo in the treatment of vasomotor symptoms of menopause.

Methods: This was a 12-week double-blind trial of 220 healthy postmenopausal women with > or = 8 moderate to severe hot flushes and sweating episodes per day. Women were randomly assigned to wear transdermal placebo patches or a transdermal patch releasing 50 microg/d 17beta-estradiol alone (Vivelle) for days 1 to 14 of each cycle and a combination patch releasing 50 microg/d 17beta-estradiol plus 1 of 3 dosage levels (140, 250, or 400 microg/d) of norethindrone acetate (CombiPatch) for days 15 through 28.

Results: There was a significant (P <.001) reduction by the second week in the mean number of daily hot flushes from baseline to end point with all 3 doses of estradiol plus norethindrone acetate compared with placebo. Significant (P <.001) reductions in the mean intensity of hot flushes and sweating were also noted with estradiol plus norethindrone acetate compared with placebo. The incidences of adverse events with all 3 doses of estradiol plus norethindrone acetate and with placebo were comparable.

Conclusions: An estradiol plus norethindrone acetate transdermal delivery system administered in a continuous sequential regimen with transdermal estradiol was well tolerated and effective for the treatment of moderate to severe vasomotor symptoms in postmenopausal women.