"Female sexual dysfunction- low libido, slow arousal, difficulty reaching orgasms and painful intercourse - is a problem that many menopausal women view as a normal part of aging and have simply decided to accept. Where men have the choice of the little blue pill, there is a lack of treatment options for women," said Subir Roy, M.D., principal investigator on the study and Professor of Obstetrics and Gynecology at the Keck School of Medicine of the University of Southern California. "The results presented today might be the first step in providing a new solution for post-menopausal women, since preliminary results show that HRT from a patch had positive effects on mood and libido, leading to more orgasms."
Although millions of postmenopausal women complain of decreased sex drive after menopause, there are currently no treatment methods for female sexual dysfunction. Preliminary research studies have indicated that testosterone and/or androgen supplements can have beneficial effects on women?s sex drive, but none are currently approved by the Food and Drug Administration (FDA) for use in women.
"Administering testosterone or androgen therapies in women is very tricky. Since we don?t have data on long-term effects and correct dosing, we often see unwanted side effects such as excessive hair growth and acne," said Dr. Roy.
"What makes our results so exciting is they indicate that HRT, when administered via a patch, allows a woman?s body to better utilize the androgens, including testosterone, she already has, resulting in improved libido."
To combat the physiologic effects of menopause, such as hot flashes and vaginal dryness, oral hormone replacement therapy (HRT), which usually involves a combination of estrogen and a synthetic version of progesterone, has traditionally been the first line treatment for women.
"The key to this study is understanding how the body responds to the different routes of HRT administration. HRT taken orally tends to reduce androgens that are later transformed by the body into testosterone. Furthermore, oral HRT increases sex-hormone binding globulin (SHBG), leading to lower amounts of free testosterone available. These lowered levels of androgens, including free testosterone, are associated with decreased libido in postmenopausal women. The results of our study showed that patch users, in comparison to oral HRT users, have higher levels of androgens, including free testosterone, and a greater degree of sexual satisfaction," said Dr. Roy.
While many different brands of oral HRT are available to women, at the present time, only one combination estrogen/progestin patch has been FDA-approved in the U.S.- CombiPatch®, the product used in the transdermal arm of this study.
"The stereotype of older people not being interested in having good sex just isn?t true," said Terry Linehan, a study participant from Los Angeles, California. "A satisfying sex life is very important to most marriages, no matter what your age. I wasn?t looking for a miracle pill or a quick fix; I just hoped that if the reason behind my low libido was due to my hormone levels that I could help find a way to regulate the problem."
"Since our study group, which consisted of 23 postmenopausal women with no mood or affective disorder, was very small, these results are only preliminary," said Dr. Roy. "Nevertheless, this is an exciting first step in validating that transdermal HRT could, and possibly should, be considered a first-line treatment for postmenopausal women with or without female sexual dysfunction, before attempting androgen or testosterone therapies. Larger and longer investigations, which are underway, will be able to verify what our results suggest."
Future trials to further investigate these findings are planned to be supported in part by Novogyne Pharmaceuticals, marketer of CombiPatch. Novogyne Pharmaceuticals is a joint venture between Novartis Pharmaceuticals Corporation and Noven Pharmaceuticals, Inc.