Vaginal Testosterone Shows Benefit in Postmenopausal Women

MIAMI — Postmenopausal women with frequent urinary tract infections benefited from vaginal testosterone (VT) cream, interim data from the randomized, double-blind placebo-controlled PIVoT trial suggested.

Women in the VT group saw improvements in vaginal health and sexual function scores at 9 months compared with placebo, although the placebo group’s sexual function scores also improved, reported Mariela Martinez, MD, MS, of Maimonides Medical Center in New York City, in a presentation at the Sexual Medicine Society of North America (SMSNA) annual meeting.

In the VT group, Vaginal Health Index (VHI) scores rose significantly from 14.65 to 17.50 (P=0.04) at 9 months. This increase in VHI scores did not occur in the placebo group.

At 9 months, Female Sexual Function Index (FSFI) scores rose from 11.17 to 13.52 in the VT group, and from 13.90 to 20.17 in the placebo group.

“We know that there are androgen receptors like testosterone receptors in the vaginal epithelium, but their function and how it works for sexual function is not known yet,” Martinez told MedPage Today. “So finding anything that has to do with vaginal health with the active ingredient that we’re looking at is actually something that was very surprising to us.”

The 44 women enrolled in the study had VHI and FSFI scores assessed at baseline and were placed randomly into control and placebo groups. Follow-up occurred at 1, 4, and 9 months.

Vaginal swabs were taken and vaginal exams were conducted at both baseline and follow-up, which were factored into VHI and FSFI scores at each stage. The VHI assesses vaginal elasticity, secretions, pH, epithelial mucosa, and hydration, with scores ranging between 5 and 25. The FSFI questionnaire evaluates desire, arousal, lubrication, orgasm, satisfaction, and pain, with a range of 2 to 36 points.

The VT arm saw improvements in FSFI components including desire (from 2.18 to 2.85), lubrication (1.74 to 2.175), orgasm (1.64 to 2.5), and pain (0.91 to 1.3) at month 9.

Women using placebo cream also had improvements in these areas, although the placebo group had higher FSFI scores at baseline (13.90, compared with 11.17 in the VT arm). This may be because there were more women in the treatment group lost to follow-up and fewer who were sexually active, Martinez said. In addition, “any sort of lubrication that they’re using regularly” may have helped the placebo group’s scores,” she noted.

Many women, including over half of those in the study population, are reluctant to treat vaginal atrophy and sexual dysfunction with estrogen because of perceptions that estrogen can increase breast cancer risk, Martinez observed. Vaginal testosterone may be an alternative patients might be more willing to maintain, even though much evidence supports the safety of using vaginal estrogen.

“It’s going to be another tool in our toolkit to offer to patients, because right now the offer we have is basically, ‘Here, take this estrogen cream, it doesn’t increase your risk of cancer,’ and that’s it,” Martinez said. “So it’s another tool that we can provide for patients, hopefully, in the future.”

Linda Vignozzi, MD, PhD, of the University of Florence in Italy, who wasn’t involved with the study, said the findings showed promise, building on earlier research she conducted in rats that suggested female testosterone wasn’t simply a precursor to estradiol in the vagina, but had its own distinct role.

“Testosterone is a very important hormone for female sexuality, and we are not to be afraid to give testosterone … because [the] vagina and clitoris are a good target for testosterone activity,” Vignozzi said. “I’m very partial to this work because it demonstrated that it functioned very well.”

The researchers looked at improvements in the rates of urinary tract infections and vaginal flora, but did not report those outcomes. The interim analysis also did not assess urinary incontinence, although Martinez said researchers would evaluate incontinence measures as part of the overall study.

Some patients were lost to follow-up throughout the study, and some follow-up appointments were still pending. Higher enrollment and longer treatment follow-up may paint a clearer picture of the effects of vaginal testosterone on sexual function in postmenopausal women, Martinez said.