Endometrial safety of ultra-low-dose Vagifem 10 μg in postmenopausal women with vaginal atrophy

Endometrial safety of low-dose vaginal estrogens

ABSTRACT

It is estimated that up to 50% to 90% of postmenopausal women may experience genitourinary syndrome of menopause (GSM), which may have a detrimental impact on quality of life. One of the most effective modes of treatment of GSM is low-dose vaginal estrogens. Numerous studies have addressed the safety of these estrogens using endometrial biopsy and/or endometrial thickness on ultrasound. Based on these studies, the consensus is that low-dose vaginal estrogens do not substantially increase the risk of endometrial hyperplasia or cancer; however, the data are severely limited by short duration of follow-up. Although long-term trials are warranted, they are difficult to carry out, costly, and will not yield data for years. More immediate information regarding endometrial safety may be obtained from studies measuring endometrial tissue and serum concentrations of estradiol, estrone, and relevant equine estrogens after administration of different estrogen formulations and doses. This would allow us to understand better the metabolism of estrogens by the vagina and endometrium, and how much estrogen is reaching the endometrium. Here, we discuss metabolism, receptor binding, and signaling of estrogens in vaginal and endometrial tissue, and summarize the existing studies on the endometrial impact of low-dose vaginal estrogen treatment in postmenopausal women.

Safety of vaginal estrogens: a systematic review

OBJECTIVE

This systematic review included clinical trials of Food and Drug Administration-approved vaginal estrogens. The primary objective of this systematic review was to examine the comparative safety of the Food and Drug Administration-approved vaginal estrogen preparations among postmenopausal women.

METHODS

We performed a PubMed search of the primary literature from January 1, 1966 to July 16, 2019 for English-language clinical trials. Manual review of retrieved citations identified additional citations.

RESULTS

Of 882 retrieved citations, 75 clinical trials met inclusion criteria. Maximum trial duration was 52 weeks. None of the trials predesignated breast or endometrial cancer, cardiovascular events, or venous thromboembolism as primary outcomes. Studies were not designed to rule out an increase in endometrial carcinoma risk with long-term use of vaginal estrogen. There were few head-to-head comparisons. Fifty trials examined serum sex steroid and gonadotrophin levels; assay methodologies varied. Serum estradiol levels were 11 pg/mL at baseline or during placebo use and increased to a mean of 30 pg/mL after treatment. Estradiol levels were usually highest during the first 12 weeks of treatment, and were higher for estrogen creams than for inserts or rings. The 22 trials of endometrial thickness and the 15 trials of endometrial biopsy did not clearly demonstrate endometrial proliferation after vaginal estrogen treatment, but data were limited, and studies did not always perform systematic endometrial biopsy.

CONCLUSIONS

Newer low-dose estradiol rings, tablets, and inserts appear to induce the least increases in serum hormones, possibly indicating greater safety. Limited evidence in trials lasting up to 52 weeks suggest endometrial safety of vaginal estrogen use. Long-term trials are needed. : Video Summary:http://links.lww.com/MENO/A513.

Endometrial safety of low-dose vaginal estrogens in menopausal women: a systematic evidence review

OBJECTIVE

The aim of the study was to systematically review studies that evaluated endometrial hyperplasia or cancer incidence with unopposed vaginal estrogens.

METHODS

PubMed and EMBASE were searched from inception to August 2017 for relevant articles and abstracts. Bibliographies of review articles and abstracts of major women's health medical meetings were examined. Eligible studies (independently reviewed by 4 authors) had to report menopausal vaginal estrogen use and endometrial histology, or incidence of endometrial hyperplasia or cancer.

RESULTS

Of 5,593 abstracts from the literature search and 47 articles from other sources, 36 articles and 2 abstracts were eligible, describing 20 randomized controlled studies, 8 interventional studies, and 10 observational studies. Collectively, the studies did not support an increased risk of endometrial hyperplasia or cancer with low-dose vaginal estrogens. Rates of endometrial cancer and hyperplasia were 0.03% and 0.4%, respectively, from 20 randomized controlled trials (2,983 women) of vaginal estrogens. Overall, reports of endometrial hyperplasia were observed with various doses and durations and appeared sporadic (except 1.25 mg conjugated equine estrogens), consistent with endometrial hyperplasia rates in the general population. A Denmark registry study was an exception and may be of limited applicability to the United States. The Women's Health Initiative Observational Study showed no association (1.3 cases/1,000 women-years with vaginal estrogens versus 1.0/1,000 women-years for nonuse).

CONCLUSION

This systematic review supports the use of low-dose vaginal estrogens for treating vulvar and vaginal atrophy in menopausal women without a concomitant progestogen. This review does not support increased endometrial hyperplasia or cancer risk with low-dose, unopposed vaginal estrogens; however, longer-term, real-world data are needed.

Systemic estradiol levels with low-dose vaginal estrogens

OBJECTIVES

To critically evaluate published systemic estradiol levels during use of low-dose vaginal estrogens considering detection method and estrogen dose; describe challenges with accurately measuring estradiol; and determine the normal estradiol level range in postmenopausal women.

METHODS

PubMed was searched for studies reporting systemic estradiol levels with lower-dose vaginal estrogens (≤25 μg estradiol or 0.3 mg conjugated equine estrogens). Estradiol levels at baseline and during treatment, area under the curve, and maximum estradiol concentrations were summarized by dose within assay type. A proposed range of systemic estradiol in normal, untreated, postmenopausal women was estimated by conservatively pooling means and standard deviations from published studies.

RESULTS

Mean basal estradiol levels were 3.1 to 4.9 pg/mL using liquid or gas chromatography/mass spectroscopy (LC or GC/MS/MS) with a range of undetectable to 10.5 pg/mL using radioimmunoassay. Systemic estradiol levels with vaginal estrogens reflected their doses as measured with LC or GC/MS/MS in different studies: 7.1 to 9.1 pg/mL and 16.7 to 22.7 pg/mL with a 25-μg softgel capsule insert and a tablet insert, respectively; 4.6 to 7.4 pg/mL and 6.6 to 14.8 pg/mL with a 10-μg softgel capsule and a tablet insert, respectively; and 3.6 to 3.9 pg/mL with a 4-μg softgel capsule insert. A mean systemic estradiol concentration ranging from undetectable to 10.7 pg/mL is proposed as an estimate for basal estradiol levels in normal, untreated, postmenopausal women. Systemic estradiol absorption may be influenced by the placement of estradiol higher (as with an applicator) versus lower (as without an applicator) in the vagina, as estradiol transport to the uterus would be more likely further away than closer to the introitus.

CONCLUSION

Serum estradiol concentrations were generally lower when measured with more specific and sensitive assays. Estradiol absorption was dose-dependent, and may be influenced by dose, formulation, and positioning in the vagina. Very low systemic estradiol absorption with low/ultralow-dose vaginal estrogens may potentially decrease any adverse events that may be associated with higher doses of vaginal estrogens used for treating moderate to severe VVA due to less estradiol exposure.

BMS - Consensus statement

Urogenital atrophy is more common than it would first appear and women do not always seek advice and guidance. Confusion still exists between systemic hormone replacement therapy (HRT) and local estrogen preparations but new treatment modalities have emerged that extend the range of options beyond lubricants, moisturisers and vaginal estrogen preparations.

The REJOICE trial: a phase 3 randomized, controlled trial evaluating the safety and efficacy of a novel vaginal estradiol soft-gel capsule for symptomatic vulvar and vaginal atrophy

Supplemental Digital Content is available in the text

Objective:

To evaluate the safety and efficacy of TX-004HR vaginal estradiol soft-gel capsules for moderate-to-severe dyspareunia associated with postmenopausal vulvar and vaginal atrophy.

Methods:

In this randomized, double-blind, placebo-controlled, phase 3 study, postmenopausal women with a self-identified most bothersome symptom of dyspareunia received 4, 10, or 25 μg TX-004HR or placebo for 12 weeks. Four co-primary efficacy endpoints were change from baseline to week 12 in percentages of superficial and parabasal cells, vaginal pH, and severity of dyspareunia. Secondary endpoints included severity of vaginal dryness and vulvar and/or vaginal itching or irritation. Endometrial histology and adverse events (AEs) were included in the safety endpoints.

Results:

In all, 764 women were randomized (modified intent-to-treat population, n = 747; mean age 59 y). Compared with placebo, all three doses of TX-004HR significantly improved the four co-primary endpoints (P < 0.0001 for all, except dyspareunia with 4 μg, P = 0.0149). Changes in cytology, pH, and dyspareunia were also significant at weeks 2, 6, and 8. Vaginal dryness and vaginal itching/irritation improved. Sex hormone binding globulin concentrations did not change with treatment. TX-004HR was well-tolerated, with no clinically meaningful differences in treatment-emergent AEs versus placebo, and no treatment-related serious AEs or deaths.

Conclusions:

TX-004HR (4, 10, and 25 μg) was safe, well-tolerated, and effective for treating moderate-to-severe dyspareunia within 2 weeks with minimal systemic estrogen exposure. This novel product may be a potential new treatment option for women experiencing postmenopausal vulvar and vaginal atrophy.

Breast cancer, endometrial cancer, and cardiovascular events in participants who used vaginal estrogen in the Women's Health Initiative Observational Study

OBJECTIVE

To determine the association between use of vaginal estrogen and risk of a global index event (GIE), defined as time to first occurrence of coronary heart disease (CHD), invasive breast cancer, stroke, pulmonary embolism, hip fracture, colorectal cancer, endometrial cancer, or death from any cause.

METHODS

For this prospective observational cohort study, we used data from participants of the Women's Health Initiative Observational Study, who were recruited at 40 US clinical centers, aged 50 to 79 years at baseline and did not use systemic estrogen therapy during follow-up (n = 45,663, median follow-up 7.2 years). We collected data regarding incident CHD, invasive breast cancer, stroke, pulmonary embolism, hip fracture, colorectal cancer, endometrial cancer, death, and self-reported use of vaginal estrogen (cream, tablet). We used Cox proportional-hazards regression models to adjust for covariates.

RESULTS

Among women with an intact uterus, the risks of stroke, invasive breast cancer, colorectal cancer, endometrial cancer, and pulmonary embolism/deep vein thrombosis were not significantly different between vaginal estrogen users and nonusers, whereas the risks of CHD, fracture, all-cause mortality, and GIE were lower in users than in nonusers (GIE adjusted hazard ratio 0.68, 95% confidence interval 0.55-0.86). Among hysterectomized women, the risks of each of the individual GIE components and of the overall GIE were not significantly different in users versus nonusers of vaginal estrogen (GIE adjusted hazard ratio 0.94, 95% confidence interval 0.70-1.26).

CONCLUSIONS

The risks of cardiovascular disease and cancer were not elevated among postmenopausal women using vaginal estrogens, providing reassurance about the safety of treatment.

A low dose (6.5 mg) of intravaginal DHEA permits a strictly local action while maintaining all serum estrogens or androgens as well as their metabolites within normal values

OBJECTIVE

Serum concentrations of estradiol (E2) and testosterone (testo) measured by mass spectrometry-based assays should remain below the 95th centile measured at 9.3 pg/mL for E2 and 0.26 ng/mL for testo in normal postmenopausal women in order to avoid the risk of non-physiological systemic exposure to elevated serum concentrations of these two sex steroids.

METHODS

Serum E2 and testo, as well as dehydroepiandrosterone (DHEA) and nine of its other metabolites, were measured at 10 time intervals over 24 h on the first and seventh days of daily intravaginal administration of 0.50% (6.5 mg) DHEA by validated mass spectrometry-based assays.

RESULTS

No biologically significant change in the individual serum concentrations of E2, testo or DHEA was observed. Most importantly, estrone sulfate (E1-S) and the glucuronidated androgen metabolites also remained within normal values, thus confirming the absence of biologically significant systemic exposure in line with intracrinology. Using data from the literature, comparison is made with serum E2 above normal postmenopausal values following administration of 10-μg E2 tablets.

CONCLUSION

While the clinical program on vulvovaginal atrophy has shown the efficacy and safety of intravaginal 6.5 mg of DHEA (prasterone), the present data illustrate in detail the serum levels of the individual sex steroids and their metabolites derived from DHEA. The data obtained are in line with the physiology of intracrinology and confirm an action limited to the vagina as the serum concentrations of all sex steroids are maintained within the normal values of menopause, thus protecting the uterus and most likely other tissues.

The role of local estrogen therapy in the management of pelvic floor disorders

Pelvic floor disorders are common and bothersome problems that include a variety of conditions. These conditions greatly affect the performance of daily activities and social function such as work, traveling, physical exercise, sleep and sexual function. Aging is a well-known factor affecting the pelvic floor and lower urinary tract anatomy and function. It is clear that the pelvic organs and their surrounding muscular and connective tissue support are estrogen-responsive. Treatment of pelvic floor disorders requires significant health-care resources and their impact is likely to increase in the near future. This literature review aims to provide an overview of both research and clinical aspects of the pathophysiology of urogenital estrogen deficiency and the role of local estrogen therapy as part of the management strategy of different pelvic floor disorders. The safety and risk concerns regarding the use of local estrogen therapy are addressed as well.

Does vaginal estrogen treatment with support pessaries in vaginal prolapse reduce complications?

OBJECTIVE

Pelvic organ prolapse is often co-existant with atrophy of the genital tract in older women who tend to prefer vaginal pessaries for prolapse. Vaginal estrogen therapy is used by some along with a support pessary for prolapse with no robust evidence to back this practice. We aimed to evaluate differences in complications of support pessaries for vaginal prolapse in postmenopausal women, with and without vaginal estrogen use.

STUDY DESIGN

We prospectively assessed postmenopausal women attending the urogynaecology clinic for a pessary change. We asked them about the level of discomfort during pessary change (visual analogue scale for pain), discharge, bleeding and infection. Ethics approval was not required as this was a service evaluation project. Statistical analysis for relative risk was performed, including sub-group analysis for 'ring pessary' and 'non-ring group' (Shelf, Gellhorn, Shaatz).

RESULTS

Between July 2013 and December 2014, we assessed 120 postmenopausal women using support pessaries for prolapse. The mean age was 70 years; 45% of the patients used vaginal estrogen. There were no statistically significant differences in complications with or without vaginal estrogen use, although the trend was higher amongst non-users. The 'non-ring' sub-group not using vaginal estrogen had a higher risk of vaginal ulceration, bleeding and discharge.

CONCLUSION

Postmenopausal women may have lesser complications when using vaginal estrogen with a support pessary for prolapse, particularly with pessaries other than the ring. An adequately powered randomised controlled trial is needed to assess conclusively whether vaginal estrogen enhances comfort and reduces complications of support pessaries for prolapse.

Dehydroepiandrosterone intra vaginal administration for the management of postmenopausal vulvovaginal atrophy

The effects of intravaginal administration of dehydroepiandrosterone (DHEA) for the management of symptomatic vulvovaginal atrophy are reviewed. A literature search related to vulvovaginal atrophy, vaginal atrophy, atrophic vaginitis, estrogen, dehydroepiandrosterone, vulvar itching, burning, dryness, dyspareunia, and libido was performed. Relevant articles addressing the incidence, management, and outcome of DHEA therapy were identified and used for this Expert Opinion. DHEA compared to a placebo is an effective treatment improving symptoms of vaginal atrophy: dyspareunia, burning, itching, and dryness. Objective parameters of vaginal atrophy, specifically pH, vaginal maturation index (VMI), and investigator-evaluated changes in the vagina: moisture, epithelia integrity and color were improved compared to baseline and placebo. There were significant improvements in libido and dyspareunia with the intravaginal use of DHEA that contribute to improved quality of life for postmenopausal women. Dehydroepiandrosterone administered intravaginally on a daily basis is an effective treatment for symptoms, and signs of vulvovaginal atrophy along with libido in postmenopausal women. This article is part of a Special Issue entitled 'Essential role of DHEA'.

Urogenital atrophy

The British Menopause Society Council aims to aid health professionals in providing up to date and informed advice about post reproductive health. This guidance refers to the long-term, but often ignored condition of urogenital atrophy resulting from postmenopausal estrogen deficiency. Treatment should be based on up to date information and targeted to the needs of the individual woman. Non-estrogen- and estrogen-containing treatments are discussed.

Management of symptomatic vulvovaginal atrophy: 2013 position statement of The North American Menopause Society

OBJECTIVE

To update and expand the previous position statement of The North American Menopause Society (NAMS) on the management of symptomatic vulvovaginal atrophy (VVA) in postmenopausal women.

METHODS

NAMS searched PubMed for medical literature on VVA published since their 2007 position statement on the role of local vaginal estrogen for treatment of vaginal atrophy in postmenopausal women. A panel of acknowledged experts in the field of genitourinary health reviewed the literature to evaluate new evidence on local estrogen as well as on other management options available or in development for symptomatic VVA. The panel's conclusions and recommendations were reviewed and approved by the NAMS Board of Trustees.

RESULTS

Symptomatic VVA can significantly impair the quality of life (QOL) of postmenopausal women and may be underdiagnosed. In most cases, it can be managed successfully. A number of over-the-counter and government-approved prescription therapies available in the United States and Canada demonstrate effectiveness, depending on the severity of VVA symptoms. These include vaginal lubricants and moisturizers, vaginal estrogen, hormone therapy, and the selective estrogen-receptor modulator ospemifene (indicated for dyspareunia). Long-term studies on the endometrial safety of local estrogen and ospemifene are lacking. Changes in the vaginal microbiome have various effects on symptoms.

CONCLUSIONS

Clinicians can improve the sexual health and QOL of postmenopausal women by educating women about, diagnosing, and appropriately managing symptomatic VVA. Choice of therapy depends on the severity of symptoms, the effectiveness and safety of therapy for the individual patient, and patient preference. Estrogen therapy is the most effective treatment for moderate to severe symptoms, although a direct comparison of estrogen and ospemifene is not available. Nonhormonal therapies available without a prescription provide sufficient relief for most women with mild symptoms. When low-dose estrogen is administered locally, a progestogen is not indicated for women without a uterus and generally is not indicated for women with an intact uterus. However, endometrial safety has not been studied in clinical trials beyond 1 year. There are insufficient data to confirm the safety of local estrogen in women with breast cancer; management of VVA should take the woman's needs and the recommendation of her oncologist into consideration. Research on the vaginal microbiome may lead to other therapies in the future.

Reviewing the options for local estrogen treatment of vaginal atrophy

BACKGROUND

Vaginal atrophy is a chronic condition with symptoms that include vaginal dryness, pain during sex, itching, irritation, burning, and discharge, as well as various urinary problems. Up to 45% of postmenopausal women may be affected, but it often remains underreported and undertreated. This article aims to review the current recommendations for treatment of vaginal atrophy, and current data on the effectiveness and safety of local vaginal estrogen therapies.

METHODS

Literature regarding vaginal atrophy (2007-2012) was retrieved from PubMed and summarized, with emphasis on data related to the treatment of vaginal atrophy with local vaginal estrogen therapy.

RESULTS

Published data support the effectiveness and endometrial safety of low-dose local estrogen therapies. These results further support the general recommendation by the North American Menopause Society that a progestogen is not needed for endometrial protection in patients using low-dose local vaginal estrogen. Benefits of long-term therapy for vaginal atrophy include sustained relief of symptoms as well as physiological improvements (eg, decreased vaginal pH and increased blood flow, epithelial thickness, secretions).

CONCLUSION

Currently available local vaginal estrogen therapies are well tolerated and effective in relieving symptoms of vaginal atrophy. Recent data support the endometrial safety of low-dose regimens for up to 1 year.

The management of lower urogenital changes in the menopause

Currently, 25% of women seek the advice of a medical professional for symptoms related to the menopause. However, with an increasingly ageing and medically aware population, it is likely this proportion will grow. The main symptoms related to the menopause are systemic vasomotor and localized urogenital symptoms. Numerous forms of estrogen have been used to alleviate these symptoms. Further problems that increase during the menopause include incontinence, pelvic organ prolapse and recurrent urinary tract infections. This article reviews the process by which estrogen affects the tissues of the urogenital tract, what symptoms occur during this period and what modalities of treatments are available.

An overview of chronic vaginal atrophy and options for symptom management

During the menopausal transition and after menopause, up to 45 percent of women will develop vaginal atrophy as a consequence of decreased levels of circulating estrogen. Symptoms include vaginal dryness, itching, soreness, bleeding, increased susceptibility to infection and pain with sexual intercourse. Treatments are often underused because of patient and clinician lack of knowledge of available treatments, embarrassment about initiating a discussion of symptoms and reluctance to initiate hormonal therapy. Methods of symptom management include self-care with over-the-counter agents and prescription treatment with various forms of localized estrogen. Clinicians should consider each woman's unique situation and health history before recommending a management strategy.

Treatment of postmenopausal vaginal atrophy with 10-μg estradiol vaginal tablets

Postmenopausal estrogen deficiency can lead to symptoms of urogenital atrophy. Individuals with urogenital atrophy have symptoms that include vaginal dryness, vaginal and vulval irritation, vaginal soreness, pain and burning during urination (dysuria), increased vaginal discharge, vaginal odour, vaginal infections, recurrent urinary tract infections, pain associated with sexual activity (dyspareunia) and vaginal bleeding associated with sexual activity. Despite the frequency and effects of vaginal atrophy symptoms, they are often under-reported and, consequently, under-treated. Therefore, care of a menopausal woman should include a physical assessment of vaginal atrophy and a dialogue between the physician and the patient that explores existing symptoms and their effect on vulvovaginal health, sexuality and quality-of-life issues. The development of the ultra-low-dose 10-µg estradiol vaginal tablets is in line with the requirements of regulatory agencies and women's health societies regarding the use of the lowest effective hormonal dose. Because of its effectiveness and safety profiles, in addition to its minimal systemic absorption, the 10-µg estradiol vaginal tablet can offer greater reassurance to health-care providers and postmenopausal women with an annual estradiol administration of only 1.14 mg.

Endometrial cancer, types, prognosis, female hormones and antihormones

Endometrial cancer covers several different types, the most prevalent in the developed world being endometrioid adenocarcinoma, which is estrogen-dependent and has a better prognosis compared to the non-estrogen-dependent types, e.g. papillary serous adenocarcinoma and clear cell carcinomas. Prognosis is also dependent on tumor differentiation and stage, and treatment should be adjusted accordingly. In this paper, the different types of endometrial cancer, staging, prognosis, diagnosis, prevention, treatment and their relationship to estrogen and other female hormones are reviewed.

Efficacy and safety of ultra-low-dose Vagifem (10 mcg)

Vulvovaginal atrophy [VVA] is defined as inflammation of the vaginal epithelium due to atrophy secondary to decreased levels of circulating estrogen. There is currently only one approved method for the treatment of VVA, and that is the administration of exogenous estrogens. Overall, the ideal VVA treatment must have benefits, minimize risks, and enhance compliance in the patient while optimizing cost-effectiveness. Unfortunately, of the approximate 25% of symptomatic women that are thought to seek medical help, the proportion that receives hormone therapy may be small and its duration of use is short. Women have been very reluctant to take hormone therapy due to widely publicized results of the risks associated with hormone therapy. Thus, while menopausal hormone therapy was once accepted as the ideal approach for optimizing changes associated with menopause, prospective randomized clinical trials have challenged that view and have led to a marked decrease in the use of such therapy and increased search for low-dose therapies. This article will highlight the efficacy and safety of recently FDA-approved Vagifem (10 mcg) in treatment of VVA.

Recommendations for the management of postmenopausal vaginal atrophy

Unlike hot flushes and night sweats which resolve spontaneously in time, atrophic symptoms affecting the vagina and lower urinary tract are often progressive and frequently require treatment. The prevalence of vaginal dryness increases as a woman advances through the postmenopausal years, causing itching, burning and dyspareunia, and sexual activity is often compromised. But, despite the various safe and effective options, only a minority (about 25% in the Western world and probably considerably less in other areas) will seek medical help. Some of this reluctance is due to the adverse publicity for hormone replacement therapy (HRT) over recent years that has suggested an increased risk of breast cancer, heart disease and stroke. But, regardless of whether these scares are justified, local treatment of vaginal atrophy is not associated with these possible risks of systemic HRT. Other reasons for the continued suffering in silence may be cultural and an understandable reluctance to discuss such matters, particularly with a male doctor, but the medical profession must also take much of the blame for failing to enquire of all postmenopausal women about the possibility of vaginal atrophic symptoms. Vaginal dryness can be helped by simple lubricants but the best and most logical treatment for urogenital atrophy is to use local estrogen. This is safe, effective and with few contraindications. It is hoped that these guidelines and recommendations, produced to coincide with World Menopause Day 2010, will help to highlight this major cause of distress and reduced quality of life and will encourage women and their medical advisers all over the world to seek and provide help.