NEW YORK (Reuters Health) – The transdermal estradiol gel 0.1% (Divigel) is effective for relieving moderate to severe vasomotor symptoms associated with menopause regardless of the woman’s age and whether or not she’s had a hysterectomy or oophorectomy.

That’s according to a post hoc analysis of data from the phase III trial that led to the product’s approval by the US Food and Drug Administration 3 years ago.

Dr. Richard E. Hedrick with Hawthorne OB/GYN Associates in Winston-Salem, North Carolina and colleagues note in their report that current treatment guidelines for menopausal vasomotor symptoms suggest that estrogen therapy should be given at the lowest effective dose and for shortest possible.

Transdermal Divigel contains 1 mg estradiol per 1 g of gel, and is available in the US in 1.0, 0.5 and 0.25 g doses. The pivotal trial involved 488 women who had undergone menopause and were assigned to one of the three doses or placebo.

In the current analysis, Dr. Hedrick and colleagues stratified the results by the participants’ age — less than 50 years, 50 to 59, and 60 or older — and by their uterine and ovarian status (either intact or absent).

The investigators report in the journal Menopause online August 16 that none of these factors affected the efficacy of the gel.

Specifically, the team found, “When treatment groups were pooled, estradiol gel 0.1% reduced both the frequency and severity of moderate to severe vasomotor symptoms from baseline in postmenopausal women in each age group.”

Similarly, when dosage groups were pooled, the product significantly reduced the frequency and severity of symptoms regardless of uterine status and ovarian status.

In discussing the results, the authors note that treatment effects were appreciable in women over 50. “Interestingly,” they add, “estradiol gel 0.1% significantly relieved vasomotor symptoms in the oldest of women (60 y and older), suggesting that treatment initiated years beyond the menopausal transition remains efficacious in treating vasomotor symptoms.”

They conclude, “Transdermal estradiol gel 0.1% has expanded the non-oral, low-dose options for the individualization of estrogen therapy and offers the lowest therapeutic dose indicated for the treatment of moderate to severe vasomotor symptoms.”

Financial support for the current study came from Upsher-Smith Laboratories, Inc., Minneapolis, Minnesota, the manufacturer of Divigel.

Reference:

Estradiol gel 0.1% relieves vasomotor symptoms independent of age, ovarian status, or uterine status

Menopause 2010;17.