Bleeding profile and endometrial safety of continuous combined regimens 1 mg 17beta-estradiol/trimegestone versus 1 or 2 mg 17beta-estradiol/norethisterone acetate in postmenopausal women

Progestogens for endometrial protection in combined menopausal hormone therapy: A systematic review

Menopausal women with an intact uterus choosing estrogens for menopausal symptom relief require a progestogen for endometrial protection. The aim of this systematic review was to evaluate the risks of endometrial hyperplasia resp. malignancy with different progestogens used in combined MHT. Overall, 84 RCTs were included. We found that 1) most studies were done with NETA, followed by MPA, MP and DYD and LNG, 2) most progestogens were only available as oral formulations, 3) the most frequently studied progestogens (oral MP, DYD, MPA, oral and transdermal NETA, transdermal LNG) were assessed in continuously as well as in sequentially combined MHT regimens, 4) FDA endometrial safety criteria were only fulfilled for some progestogen formulations, 5) most studies demonstrated endometrial protection for the progestogen dose and time period examined. However, 6) study quality varied which should be taken into account, when choosing a combined MHT, especially if off-label-use is chosen.

Uterine bleeding with hormone therapies in menopausal women: a systematic review

Uterine bleeding is a common reason why women discontinue menopausal hormone therapy (HT). This systematic review compared bleeding profiles reported in studies for continuous-combined HT approved in North America and Europe for moderate to severe vasomotor symptoms in postmenopausal women with a uterus. Non-head-to-head studies showed that uterine bleeding varies by formulation and administration route, with oral having a better bleeding profile than transdermal formulations. Cumulative amenorrhea over a year ranged from 18 to 61% with oral HT and from 9 to 27% with transdermal HT, as reported for continuous-combined HT containing 17β-estradiol (E2)/progesterone (P4) (56%), E2/norethisterone acetate (NETA) (49%), E2/drospirenone (45%), conjugated equine estrogens/medroxyprogesterone acetate (18-54%), ethinyl estradiol/NETA (31-61%), E2/levonorgestrel patch (16%), and E2/NETA patch (9-27%). Amenorrhea rates and the mean number of bleeding/spotting days improved over time. The oral E2/P4 combination was amongst those with lower bleeding rates and may be an appropriate alternative for millions of women seeking bioidentical HT and/or those who have bleeding concerns with other HT.

Effectiveness, tolerability and acceptance of an oral estradiol/levonorgestrel formulation for the treatment of menopausal complaints: a non-interventional observational study over six cycles of 28 days

BACKGROUND

Use of hormone therapy for menopausal complaints is a subject of controversy and increased uncertainty and concerns. This non-interventional study aimed to investigate a marketed oral formulation containing 1 mg estradiol and 0.04 mg levonorgestrel for continuous treatment of menopausal symptoms for approximately 6 months in women visiting gynecological practices in Germany.

METHODS

Changes in the menopause rating scale (MRS) total and sub-domain scores after three and six 28-d cycles served as primary endpoint. Skin- and hair-related complaints, quality of sexual life and subjective satisfaction with the treatment were assessed. Adverse drug reactions (ADRs), adverse events (AEs) and vaginal bleeding were evaluated.

RESULTS

MRS scores improved significantly above 5 points of clinical relevance as compared to baseline (n = 736, p < 0.0001). Skin- and hair-related symptoms abated; quality of sexual life improved. AEs were registered in 9.9% of the participants. No unexpected ADRs were reported. Bleeding episodes consistently decreased; >75% of the subjects were amenorrheic throughout the study. Medication's effectiveness and tolerability was rated very good/good by >80% of the participants, who also continued treatment.

CONCLUSION

This estradiol/low-dose levonorgestrel formulation safely alleviates menopausal symptoms in peri- and postmenopausal women with add-on benefits regarding dermatological and sexual life complaints.

Discriminating the endogenous and exogenous urinary estrogens in human by isotopic ratio mass spectrometry and its potential clinical value

Estrogens were prohibited in the food producing animals by European Union (96/22/EC directive) and added to the Report on Carcinogens in United States since 2002. Due to very low concentration in serum or urine (~pg/mL), the method of control its abuse had not been fully developed. The endogenous estrogens were separated from urines of 18 adult men and women. The exogenous estrogens were chemical reference standards and over the counter preparations. Two patients of dysfunctional uterine bleeding (DUB) administered exogenous estradiol and the urines were collected for 72 h. The urinary estrogens were separated by high-performance liquid chromatography (HPLC) and confirmed. The exogenous and exogenous estrogens were analyzed by gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) to determine the (13)C/(12)C ratio (δ(13)C‰). The δ(13)C‰ values of reference standard of E1, E2, and E3 were -29.36±0.72, -27.98±0.35, -27.62±0.51, respectively. The δ(13)C‰ values of the endogenous E1, E2, and E3 were -21.62±1.07, -22.14±0.98, and -21.88±1.16, with P<0.01 (t-test). Two DUB patients' urinary estradiol δ(13)C‰ values was depleted to -28.02±0.33 after the administration. The progesterone, 17α-hydroxyprogesterone, pregnanediol, as well as desogestrel and ethinylestradiol from contraceptives were also determined. Stable carbon isotope analysis can distinguish the endogenous and exogenous urinary estrogen in human.

Hormone therapy in postmenopausal women and risk of endometrial hyperplasia

BACKGROUND

Reduced circulating estrogen levels around the time of the menopause can induce unacceptable symptoms that affect the health and well-being of women. Hormone therapy (both unopposed estrogen and estrogen/progestogen combinations) is an effective treatment for these symptoms, but is associated with risk of harms. Guidelines recommend that hormone therapy be given at the lowest effective dose and treatment should be reviewed regularly. The aim of this review is to identify the minimum dose(s) of progestogen required to be added to estrogen so that the rate of endometrial hyperplasia is not increased compared to placebo.

OBJECTIVES

The objective of this review is to assess which hormone therapy regimens provide effective protection against the development of endometrial hyperplasia or carcinoma.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched January 2012), The Cochrane Library (Issue 1, 2012), MEDLINE (1966 to January 2012), EMBASE (1980 to January 2012), Current Contents (1993 to May 2008), Biological Abstracts (1969 to 2008), Social Sciences Index (1980 to May 2008), PsycINFO (1972 to January 2012) and CINAHL (1982 to May 2008). Attempts were made to identify trials from citation lists of reviews and studies retrieved, and drug companies were contacted for unpublished data.

SELECTION CRITERIA

Randomised comparisons of unopposed estrogen therapy, combined continuous estrogen-progestogen therapy, sequential estrogen-progestogen therapy with each other or placebo, administered over a minimum period of 12 months. Incidence of endometrial hyperplasia/carcinoma assessed by a biopsy at the end of treatment was a required outcome. Data on adherence to therapy, rates of additional interventions, and withdrawals owing to adverse events were also extracted.

DATA COLLECTION AND ANALYSIS

In this update, 46 studies were included. Odds ratios (ORs) were calculated for dichotomous outcomes. The small numbers of studies in each comparison and the clinical heterogeneity precluded meta-analysis for many outcomes.

MAIN RESULTS

Unopposed estrogen is associated with increased risk of endometrial hyperplasia at all doses, and durations of therapy between one and three years. For women with a uterus the risk of endometrial hyperplasia with hormone therapy comprising low-dose estrogen continuously combined with a minimum of 1 mg norethisterone acetate (NETA) or 1.5 mg medroxyprogesterone acetate (MPA) is not significantly different from placebo at two years (1 mg NETA: OR 0.04; 95% confidence interval (CI) 0 to 2.8; 1.5 mg MPA: no hyperplasia events).

AUTHORS' CONCLUSIONS

Hormone therapy for postmenopausal women with an intact uterus should comprise both estrogen and progestogen to reduce the risk of endometrial hyperplasia.

Contraceptives with novel benefits

INTRODUCTION

Progesterone receptor (PR) agonists (progestins) and antagonists are developed for female contraceptives. However, non-contraceptive applications of newer progestins and PR modulators are being given more attention.

AREAS COVERED

The newer PR agonists including drospirenone, nomegestrol, trimegestone, dienogest and nestorone are being evaluated as contraceptives with health benefits because of their unique pharmacological properties. The selective PR modulators (SPRM; PR antagonists with PR agonistic properties) are under development not only for emergency contraception but also for other health benefits such as the treatment of endometritis and leiomyoma. After searching the literature from PubMed, clinicaltrials.gov and patent database, this review focuses on the effects and mechanisms of these progestins, and SPRMs as contraceptives with other health benefits.

EXPERT OPINION

PR agonists and antagonists that have novel properties may generate better contraceptive effects with other health benefits.

The endometrium--from estrogens alone to TSECs

This article reviews publications dating back more than a century describing investigations of the endometrium, including those examining the relationship between endometrial hyperplasia and carcinoma, the influence of estrogens on the endometrium, and strategies for protecting the endometrium from unopposed estrogen stimulation. Endometrial hyperplasia and carcinoma studies date from before 1900. The influence of endogenous estrogens on the endometrium became evident with observations of endometrial hyperplasia and/or carcinoma in women with estrogen-secreting tumors or polycystic ovarian disease. Later, observational studies and randomized, controlled trials suggested a relationship between unopposed estrogens and endometrial cancer and hyperplasia. The first, and to date only, effective clinical strategy for protecting the endometrium from unopposed estrogen stimulation has been the use of progestins. A new approach for endometrial protection in menopausal therapy is the pairing of a selective estrogen receptor modulator (SERM) with estrogen(s), also known as a tissue selective estrogen complex (TSEC). Effective protection of the endometrium as well as treatment of menopausal symptoms and prevention of osteoporosis would be key elements for a clinically useful TSEC.

Hormone therapy in postmenopausal women and risk of endometrial hyperplasia

BACKGROUND

Declining circulating estrogen levels around the time of the menopause can induce unacceptable symptoms that affect the health and well being of women. Hormone therapy (both unopposed estrogen and estrogen/progestogen combinations) is an effective treatment for these symptoms, but is associated with risk of harms. Guidelines recommend that hormone therapy be given at the lowest effective dose and treatment should be reviewed regularly. The aim of this review is to identify the minimum dose(s) of progestogen required to be added to estrogen so that the rate of endometrial hyperplasia is not increased compared to placebo.

OBJECTIVES

The objective of this review is to assess which hormone therapy regimens provide effective protection against the development of endometrial hyperplasia and/or carcinoma.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched January 2008), The Cochrane Library (Issue 1, 2008), MEDLINE (1966 to May 2008), EMBASE (1980 to May 2008), Current Contents (1993 to May 2008), Biological Abstracts (1969 to 2008), Social Sciences Index (1980 to May 2008), PsycINFO (1972 to May 2008) and CINAHL (1982 to May 2008). Attempts were made to identify trials from citation lists of reviews and studies retrieved, and drug companies were contacted for unpublished data.

SELECTION CRITERIA

Randomised comparisons of unopposed estrogen therapy, combined continuous estrogen-progestogen therapy and/or sequential estrogen-progestogen therapy with each other or placebo, administered over a minimum period of twelve months. Incidence of endometrial hyperplasia/carcinoma assessed by a biopsy at the end of treatment was a required outcome. Data on adherence to therapy, rates of additional interventions, and withdrawals due to adverse events were also extracted.

DATA COLLECTION AND ANALYSIS

In this substantive update, forty five studies were included. Odds ratios were calculated for dichotomous outcomes. The small numbers of studies in each comparison and the clinical heterogeneity precluded meta analysis for many outcomes.

MAIN RESULTS

Unopposed estrogen is associated with increased risk of endometrial hyperplasia at all doses, and durations of therapy between one and three years. For women with a uterus the risk of endometrial hyperplasia with hormone therapy comprising low dose estrogen continuously combined with a minimum of 1 mg norethisterone acetate or 1.5 mg medroxyprogesterone acetate is not significantly different from placebo (1mg NETA: OR=0.04 (0 to 2.8); 1.5mg MPA: no hyperplasia events).

AUTHORS' CONCLUSIONS

Hormone therapy for postmenopausal women with an intact uterus should comprise both estrogen and progestogen to reduce the risk of endometrial hyperplasia.

Preclinical and clinical properties of trimegestone: a potent and selective progestin

Trimegestone (TMG) is a novel, 19-norpregnane progestin with potent and selective properties. In preclinical studies, TMG has been shown to provide high endometrial selectivity. Further, TMG has high affinity and selectivity for the progesterone receptor and lacks the agonist effects of other steroid hormones. In clinical studies, TMG has been shown to have high endometrial safety and an improved bleeding profile along with improved tolerability compared with other progestins. In addition, TMG also does not impede the beneficial effects of estrogen, especially on bone, and does not compromise quality of life. The preclinical findings of lack of mineralocorticoid activity of TMG were supported in clinical findings, with neutral effect on body weight. Similarly, the smaller effect of TMG on the GABA-ergic (gamma-aminobutyric acid) system in preclinical studies is consistent with the improvement of central nervous system-related effects on depressed mood and sleep quality in clinical studies. Low-dose estradiol/TMG regimens provide rapid relief from menopausal symptoms, reducing the number and severity of hot flushes as effectively as 2 mg 17beta-estradiol/1 mg norethisterone acetate. Therefore, it may be concluded that TMG provides a clinically proven option in hormone therapy for both clinicians and patients.

Hormone replacement therapy in postmenopausal women: endometrial hyperplasia and irregular bleeding

BACKGROUND

The decline in circulating oestrogen around the time of the menopause often induces unacceptable symptoms that affect the health and well being of women. Hormone replacement therapy (both unopposed oestrogen and oestrogen and progestogen combinations) is an effective treatment for these symptoms. In women with an intact uterus, unopposed oestrogen may induce endometrial stimulation and increase the risk of endometrial hyperplasia and carcinoma. The addition of progestogen reduces this risk but may cause unacceptable symptoms, bleeding and spotting which can affect adherence to therapy.

OBJECTIVES

The objective of this review is to assess which hormone replacement therapy regimens provide effective protection against the development of endometrial hyperplasia and/or carcinoma with a low rate of abnormal vaginal bleeding.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched January 2003), The Cochrane Library (Issue 2, 2003), MEDLINE (1966 to January 2003), EMBASE (1980 to January 2003), Current Contents (1993 to January 2003), Biological Abstracts (1969 to 2002), Social Sciences Index (1980 to January 2003), PsycINFO (1972 to February 2003) and CINAHL (1982 to January 2003). The search strategy was developed by the Cochrane Menstrual Disorder and Subfertility Group. Attempts were also made to identify trials from citation lists of review articles and drug companies were contacted for unpublished data. In most cases, the corresponding author of each included trial was contacted for additional information.

SELECTION CRITERIA

The inclusion criteria were randomised comparisons of unopposed oestrogen therapy, combined continuous oestrogen-progestogen therapy and sequential oestrogen-progestogen therapy with each other and placebo administered over a minimum treatment period of six months. Trials had to assess which regimen was the most protective against the development of endometrial hyperplasia/carcinoma and/or caused the lowest rate of irregular bleeding.

DATA COLLECTION AND ANALYSIS

Sixty RCTs were identified. Of these 23 were excluded and seven remain awaiting assessment. The reviewers assessed the thirty included studies for quality, extracted the data independently and odds ratios for dichotomous outcomes were estimated. Outcomes analysed included frequency of endometrial hyperplasia or carcinoma, frequency of irregular bleeding and unscheduled biopsies or dilation and curettage, and adherence to therapy.

MAIN RESULTS

Unopposed moderate or high dose oestrogen therapy when compared to placebo was associated with a significant increase in rates of endometrial hyperplasia with increasing rates at longer duration of treatment and follow up. Odds ratios ranged from (1 RCT; OR 5.4, 95% CI 1.4 to 20.9) for 6 months of treatment to (4 RCTs; OR 9.6, 95% CI 5.9 to 15.5) for 24 months treatment and (1 RCT; OR 15.0, 95% CI 9.3 to 27.5) for 36 months of treatment with moderate dose oestrogen (in the PEPI trial, 62% of those who took moderate dose oestrogen had some form of hyperplasia at 36 months compared to 2% of those who took placebo). Irregular bleeding and non adherence to treatment were also significantly more likely under these unopposed oestrogen regimens that increased bleeding with higher dose therapy. Although not statistically significant, there was a 3% incidence (2 RCTs) of hyperplasia in women who took low dose oestrogen compared to no incidence of hyperplasia in the placebo group. The addition of progestogens, either in continuous combined or sequential regimens, helped to reduce the risk of endometrial hyperplasia and improved adherence to therapy. At longer duration of treatment, continuous therapy was more effective than sequential therapy in reducing the risk of endometrial hyperplasia. There was evidence of a higher incidence of hyperplasia under long cycle sequential therapy (progestogen given every three months) compared to monthly sequential therapy (progestogen given every month). No increase in endometrial cancer was seen in any of t in any of the treatment groups during the duration (maximum of six years) of these trials. During the first year of therapy irregular bleeding and spotting was more likely in continuous combined therapy than sequential therapy. However, during the second year of therapy bleeding and spotting was more likely under sequential regimens.

REVIEWERS' CONCLUSIONS

There is strong and consistent evidence in this review that unopposed oestrogen therapy, at moderate and high doses, is associated with increased rates of endometrial hyperplasia, irregular bleeding and consequent non adherence to therapy. The addition of oral progestogens administered either sequentially or continuously is associated with reduced rates of hyperplasia and improved adherence to therapy. Irregular bleeding is less likely under sequential than continuous therapy during the first year of therapy but there is a suggestion that continuous therapy over long duration is more protective than sequential therapy in the prevention of endometrial hyperplasia. Hyperplasia is more likely when progestogen is given every three months in a sequential regimen compared to a monthly progestogen sequential regimen.