Determinants of attained estradiol levels in response to oral estradiol plus progesterone therapy

OBJECTIVES

Among postmenopausal women taking hormone therapy (HT), the estradiol (E2) dose and E2 levels were differentially associated with change in metabolic measures. We evaluated determinants of attained E2 levels in response to HT.

METHODS

Postmenopausal women from the REPLENISH trial tested four formulations of oral combined E2 and progesterone compared with placebo. Mixed-effects linear models assessed characteristics associated with E2 levels among women with ≥80% HT compliance, adjusted for E2 dose and baseline E2 level.

RESULTS

Among 1173 postmenopausal women with mean (standard deviation) age 55 (4.3) years and 5.2 (4.8) years since menopause, higher treated E2 levels were significantly related to younger age, more recent menopause, and current alcohol use, while lower E2 levels were related to current smoking. Both age and time since menopause were significantly inversely associated with E2 levels; time since menopause had a stronger association with E2 levels. In the final multivariable model, E2 levels were positively associated with current alcohol use, and inversely associated with time since menopause and current smoking.

CONCLUSION

Adjusting for E2 dose and baseline E2 level, on-trial E2 levels were significantly associated with time since menopause, current smoking, and current alcohol use. Practitioners should consider these factors in individual women to achieve a desirable E2 level during HT.

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.

Association of oral estradiol dose/levels with coagulation measures in early/late postmenopausal women

Objective: This study evaluated associations of estradiol (E2) dose and serum E2 levels with coagulation/anti-coagulation measures in early (<6 years) compared with late (≥10 years) postmenopausal women.Methods: Postmenopausal women from the REPLENISH trial tested four formulations of oral combined E2 and progesterone compared with placebo. Mixed-effects linear models tested the association of E2 dose and serum E2 levels with the prothrombin time (PT), the activated partial thromboplastin time (APTT), antithrombin (ATHRM), fibrinogen (FIBRINO), protein C (PROTC), and protein S (PROTS), assessed five times over 12 months.Results: Among 1215 early and 297 late postmenopausal women, the E2 dose was statistically significantly inversely associated with the APTT in early postmenopause, PROTC in late postmenopause, and with the PT, ATHRM, and PROTS in both groups. Serum E2 levels were statistically significantly inversely associated with the APTT, PROTS, and FIBRINO in early postmenopause, the PT in late postmenopause, and ATHRM and PROTC in both groups. With longer time since menopause, the inverse E2 dose effect and serum E2 effects became stronger.Conclusion: Increasing E2 dose and serum E2 levels were associated with changes in coagulation/anti-coagulation measures. The associations were stronger among women ≥10 years since menopause when initiating E2. The timing of E2 therapy, E2 dose, and serum E2 levels relative to time since menopause may modify the venous thromboembolism risk.

Metabolic and cardiovascular effects of TX-001HR in menopausal women with vasomotor symptoms

Objective: This study aimed to evaluate the effects of TX-001HR (17β-estradiol [E2] and progesterone [P4] in a single oral capsule) on cardiometabolic markers and outcomes. Methods: Four E2/P4 doses (1 mg/100 mg, 0.5 mg/100 mg, 0.5 mg/50 mg, 0.25 mg/50 mg) were compared with placebo in menopausal women with vasomotor symptoms (VMS) and a uterus in the phase 3 REPLENISH (ClinicalTrials.gov, NCT01942668) trial. Changes in lipid and coagulation parameters and blood glucose from baseline at 6, 9, and 12 months as well as cardiovascular events are summarized. Results: A total of 1835 participants took ≥1 capsule of daily E2/P4; 1684 received E2/P4 and 151 received placebo. No clinically significant changes in lipid parameters, coagulation factors, or glucose were observed between treatment groups. Minimal increases of potential clinical importance were observed in total cholesterol, triglycerides, and glucose at month 12 with E2/P4 (1-4%, 6-11%, and 1%, respectively) and placebo (3%, 7%, and 2%, respectively). One episode of deep venous thrombosis and three cases of cardiovascular disease were observed, similar to expected rates of these events in the general population. Conclusions: In the REPLENISH trial, postmenopausal women with VMS treated with E2/P4 had no clinically meaningful effects on lipids, glucose, or coagulation parameters compared with placebo.

Evidence on the use of progesterone in menopausal hormone therapy

A need exists for a regulatory agency-approved hormone therapy (HT) with naturally occurring hormones combining progesterone (P4) and estradiol (E2), since no single product contains both endogenous hormones. Many women choose HT with P4 and millions of women around the world are using unapproved, poorly regulated compounded HT. The use of natural P4 in HT results, for the most part, in favorable outcomes without deleterious effects, as shown in clinical studies of postmenopausal women. Importantly, P4 used in HT prevents endometrial hyperplasia from estrogens while helping relieve vasomotor symptoms and improving quality-of-life measures. Additionally, risk of venous thromboembolism and breast cancer does not appear to increase with use of P4 plus estrogens as shown with synthetic progestins plus estrogens in large observations studies, and no detrimental effects of P4 in HT have been found on outcomes related to cardiovascular disease or cognition. A regulatory agency-approved HT with naturally occurring E2/P4 could be an option for the millions of women who desire a bioidentical product and/or are exposed to potential risks of inadequately studied and under-regulated compounded HT.

Pharmacokinetic studies of solubilized estradiol given vaginally in a novel softgel capsule

Objective To evaluate the bioavailability and safety of a novel vaginal capsule containing solubilized bioidentical 17β-estradiol for vulvar and vaginal atrophy and compare its pharmacokinetics with that of an approved vaginal estradiol tablet in healthy postmenopausal women.

Methods Two randomized, single-dose, two-way cross-over, relative bioavailability trials compared the pharmacokinetics of a solubilized vaginal estradiol softgel capsule (TX-004HR, test) with that of a vaginal estradiol tablet (Vagifem®, reference) in postmenopausal women (aged 40–65 years) at 10-μg and 25-μg doses. In each study, women were randomly assigned to receive a single dose of the test capsule or reference tablet, followed by a single dose of the alternate drug after a 14-day washout.

Results Thirty-five women completed the 10-μg study and 36 completed the 25-μg study. Significantly lower systemic levels of estradiol, estrone, and estrone sulfate at both doses of the test product were observed compared with equivalent doses of the reference product, with lower AUC_0-24 and C_max and earlier t_max. No adverse events were reported in either trial.

Conclusion TX-004HR, a novel estradiol vaginal softgel capsule, exhibited significantly lower systemic exposure than equivalent doses of an approved vaginal estradiol tablet at both 10-μg and 25-μg doses. Both doses of each product were safe and well-tolerated.

The utility of measuring anti-Müllerian hormone in predicting menopause

Menopause is a relevant phase in a woman's reproductive life. Accurate estimation of the time of menopause could improve the preventive management of women's health. Reproductive hormones reflect the activity of follicle pools and provide information about ovarian aging. Anti-Mu llerian hormone (AMH) is secreted from small antral follicles and its level is correlated to the ovarian reserve. AMH declines with age, and data suggest that it can provide information on menopausal age and reproductive lifespan. Serum AMH levels become low approximately 5 years before the final menstrual period and are undetectable in postmenopausal women. The majority of studies indicate that AMH is relatively stable throughout the menstrual cycle; however, there are interindividual variabilites of serum AMH concentration under different conditions. AMH is an independent predictor of time to menopause. AMH coupled with age for menopause prediction provides stronger information than using age alone. Ongoing research is focused on constructing a multivariate model including AMH values, genes related to follicular recruitment and maternal age of menopause that would predict more precisily time to menopause.

Cardiovascular safety of conjugated estrogens plus bazedoxifene: meta-analysis of the SMART trials

OBJECTIVES

Five randomized, phase-3 trials demonstrated the efficacy and safety of conjugated estrogens/bazedoxifene (CE/BZA) in treating menopausal symptoms and preserving bone. This pooled analysis of these studies describes the cardiovascular safety of CE/BZA.

METHODS

We pooled cardiovascular adjudicated safety data from healthy, non-hysterectomized, postmenopausal women who received ≥ 1 dose of CE 0.45 mg/BZA 20 mg (n = 1585), CE 0.625 mg/BZA 20 mg (n = 1583), any CE/BZA dose (n = 4868), or placebo (n = 1241) for up to 2 years in five trials. Venous thromboembolic events (VTEs), coronary heart disease (CHD), and cerebrovascular events were reviewed by three different independent adjudication committees and summarized using a meta-analytic approach.

RESULTS

The rate of VTEs per 1000 woman-years (95% confidence interval, CI) was 0.3 (0.0-2.0) in women taking CE 0.45 mg/BZA 20 mg, 0 (0.0-1.5) in those taking CE 0.625 mg/BZA 20 mg, 0.7 (0.0-1.5) among women taking any CE/BZA dose, and 0.6 (0.0-2.9) with placebo. The incidence of stroke per 1000 woman-years (95% CI) was 0.4 (0.0-2.4), 0.2 (0.0-1.9), 0.44 (0.0-1.1), and 0.0 (0.0-1.7), respectively. The CHD rate per 1000 woman-years was 2.6 (0.0-5.6), 1.4 (0.0-3.9), 2.4 (1.00-3.7) and 2.0 (0.0-5.2). Compared with placebo, relative risk (95% CI) with any CE/BZA dose was 0.5 (0.1-1.8) for VTE, 0.5 (0.1-2.6) for stroke, and 0.63 (0.23-1.74) for CHD.

CONCLUSIONS

Up to 2 years of CE 0.45 or CE 0.625 mg with BZA 20 mg had an acceptable cardiovascular safety profile, with rates of stroke and CHD comparable to placebo in healthy postmenopausal women. VTE risk was low.

Effects of bazedoxifene/conjugated estrogens on endometrial safety and bone in postmenopausal women

OBJECTIVES

Bazedoxifene/conjugated estrogens (BZA/CE) has demonstrated efficacy in improving vasomotor and vulvar/vaginal atrophy symptoms in postmenopausal women. This study evaluated the endometrial safety of BZA/CE and effects on bone mineral density (BMD) compared with CE/medroxyprogesterone acetate (MPA) and placebo.

METHODS

The Selective estrogens, Menopause, And Response to Therapy (SMART)-4 trial was a 1-year, multicenter, double-blind, randomized, placebo- and active-controlled, phase-3 study in non-hysterectomized, postmenopausal women (n = 1061; aged 40 -< 65 years). Subjects received BZA 20 mg/CE 0.45 or 0.625 mg, CE 0.45 mg/MPA 1.5 mg, or placebo daily. Primary endpoints were the incidence of endometrial hyperplasia and the change in lumbar spine BMD at 1 year. Secondary endpoints included the change in total hip BMD and rates of amenorrhea and breast pain.

RESULTS

At 1 year, no cases of endometrial hyperplasia were identified in the BZA 20-mg/CE 0.45-mg group, while three cases (1.1%) were confirmed for the BZA 20-mg/CE 0.625-mg group (95% one-sided confidence interval upper limit < 4%). Both BZA/CE doses significantly increased lumbar spine and total hip BMD versus placebo (p ≤ 0.001) and showed low incidences of bleeding and breast tenderness, similar to placebo and significantly lower than for CE 0.45 mg/MPA 1.5 mg (p < 0.05). BZA/CE treatment was generally safe and well tolerated.

CONCLUSIONS

BZA 20 mg/CE 0.45 and 0.625 mg significantly improved BMD while maintaining endometrial safety and showed a favorable safety/tolerability profile over 1 year. BZA/CE may be a promising therapy for treating menopausal symptoms and preventing osteoporosis in non-hysterectomized, postmenopausal women.

Bazedoxifene/conjugated estrogens for menopausal symptom treatment and osteoporosis prevention

Postmenopausal women with vasomotor and vaginal symptoms are commonly treated with estrogens or combined estrogen/progestin therapy (hormone therapy). However, hormone therapy is associated with some safety and tolerability concerns and its benefit/risk profile may vary for women based on their time since menopause. The tissue selective estrogen complex (TSEC) pairs a selective estrogen receptor modulator with one or more estrogens, with the goal of relieving menopausal symptoms and preserving bone mineral density without stimulating the breast or endometrium. Bazedoxifene/conjugated estrogens (BZA/CE) is the first TSEC in clinical development. BZA 20 mg/CE 0.45 and 0.625 mg have been shown in phase-3 clinical trials to significantly improve hot flushes and vulvar/vaginal atrophy measures in symptomatic postmenopausal women and to prevent bone loss in postmenopausal women at risk for osteoporosis while ensuring endometrial safety. These doses of BZA/CE have also demonstrated significant improvements in quality-of-life scores, sleep parameters, and treatment satisfaction compared with placebo. BZA 20 mg/CE 0.45 and 0.625 mg showed high cumulative rates of amenorrhea and low rates of breast pain, similar to those with placebo. The favorable treatment effects seen with BZA/CE were generally consistent in women < 5 or ≥ 5 years since menopause. Based on its demonstrated efficacy and safety in women both closer to or further from menopause, BZA/CE may be an appropriate alternative to hormone therapy for the treatment of menopausal symptoms and the prevention of osteoporosis.

Effects of bazedoxifene/conjugated estrogens on quality of life in postmenopausal women with symptoms of vulvar/vaginal atrophy

OBJECTIVE

To evaluate the effects of the tissue selective estrogen complex (TSEC) pairing bazedoxifene (BZA) with conjugated estrogens (CE) on sexual function and quality of life in postmenopausal women.

METHODS

In this 12-week, double-blind, placebo-controlled study, postmenopausal, non-hysterectomized women (n = 652) with symptoms of moderate to severe vulvar/vaginal atrophy were randomized to once-daily treatment with BZA 20 mg/CE 0.45 or 0.625 mg, BZA 20 mg, or placebo. The Arizona Sexual Experiences (ASEX) Scale, Menopause-Specific Quality of Life (MENQOL) questionnaire, and Menopause Symptoms Treatment Satisfaction Questionnaire (MS-TSQ) were secondary measures used to assess the effects of BZA/CE on sexual function, menopausal symptoms, and satisfaction with treatment, respectively.

RESULTS

At week 12, both BZA/CE doses were associated with significant improvement in ease of lubrication score from baseline compared with placebo (p < 0.05) on the ASEX scale, although there was no difference in the change in total score. The MENQOL questionnaire results at week 12 showed significant improvements in vasomotor function, sexual function and total scores with both BZA/CE doses vs. placebo or BZA 20 mg (p < 0.001). The MS-TSQ results showed that BZA/CE-treated subjects reported significantly greater overall satisfaction with treatment, as well as satisfaction with control of hot flushes during the day and night, effect on quality of sleep, and effect on mood or emotions, compared with subjects treated with placebo or BZA 20 mg (all p < 0.05).

CONCLUSION

Treatment with BZA/CE for 12 weeks was shown to significantly improve sexual function and quality-of-life measures in symptomatic postmenopausal women.

Effects of 17?-estradiol, progesterone, synthetic progestins, tibolone, and raloxifene on vascular endothelial growth factor and Thrombospondin-1 messengerRNA in breast cancer cells

To determine the effect of 17beta-estradiol, raloxifene, progesterone, medroxyprogesterone acetate (MPA), levonorgestrel (LNG), norethindrone (NET), tibolone and tibolone metabolites on vascular endothelial growth factor (VEGF) isoforms 121 and 165 and Thrombospondin-1 (TSp-1) messenger RNA (mRNA) in two breast cancer cell lines, MCF-7 and T47-D. MCF-7 and T47-D cells were cultured to 80% confluence, in vitro. After 24 h incubation in serum-free media, 1.0, 0.1, and 0.01 muM of 17beta-estradiol, raloxifene, raloxifene plus ICI 182780, tibolone, 3alpha-hydroxytibolone, and 3beta-hydroxytibolone were added to MCF-7 cells. Progesterone, MPA, LNG, NET, and Delta(4) tibolone at 1.0, 0.1, and 0.01 muM were added to T47-D cells. The cells plus steroids were incubated for a further 24 h. Total RNA was isolated using TRIZOL and reverse transcriptase-polymerase chain reaction was carried out using primers for VEGF, TSP-1, and cyclophilin, the latter as an internal control. Semiquantitative analysis was performed using 33P-CTP for radioactive labeling during the polymerase chain reaction. 17beta-estradiol, raloxifene, tibolone, 3alpha-hydroxytibolone, and 3beta-hydroxytibolone had no effect on VEGF mRNA in MCF-7 cells. Progesterone, MPA, LNG, and NET increased VEGF mRNA in T47-D cells. Delta(4) tibolone also increased VEGF mRNA but to a lesser extent than the progestogens. Raloxifene increased TSP-1 mRNA, this effect was not reversed by the addition of ICI 182780 to the media. 17beta-estradiol, raloxifene, tibolone and tibolone hydroxy-metabolites had no effect on VEGF mRNA in MCF-7 cells. Progesterone and progestins increased VEGF mRNA in T47-D breast cancer cells. Delta(4) tibolone was less effective than progestogens on this angiogenic gene in the T47-D cells. Raloxifene increased TSP-1. These differential effects may be related to breast cancer growth.

In search of candidate genes critically expressed in the human endometrium during the window of implantation

BACKGROUND

In this prospective randomized blinded clinical trial, we examined gene expression profiles of the human endometrium during the early and mid-luteal phases of the natural cycle.

METHODS

An endometrial biopsy was performed on day 16 (LH +3) or on day 21 (LH +8), followed by RNA extraction and microarray analysis using an Affymetrix HG-U95A microchip. Data analysis was carried out using pairwise multiple group comparison with the significance analysis of microarrays (SAM) software.

RESULTS

With a false discovery rate of 0, the analysis revealed that 107 genes were significantly and differently expressed (> or =2-fold) during the early versus the mid-luteal phase of the cycle. Forty-five of these genes have not been previously linked to endometrial receptivity. Validation of the microarray data was accomplished using semiquantitative RT-PCR. We demonstrated the presence of estrogen and progesterone response elements (ERE and PRE) by analysis of the 5'-flanking regions of a subset of differentially regulated genes.

CONCLUSIONS

Using a strict bioinformatics approach of microarray data, we demonstrated significant changes in candidate genes during the transition of the early to the mid-luteal phase of the human endometrium that may have functional significance for the opening and maintenance of the window of implantation.

Formation of (dA-dT)n cruciforms in Escherichia coli cells under different environmental conditions

We have detected cruciform formation of (dA-dT)n inserts in Escherichia coli cells by analyzing the superhelical density of isolated plasmid DNA samples and by probing intracellular DNA with chloroacetaldehyde. The plasmids we used were pUC19 containing inserts of (dA-dT)n. The cruciforms appeared after cells underwent different stresses: inhibition of protein synthesis, anaerbiosis, and osmotic shock. At the same time, all these stimuli led to an increase in superhelical density of the control pUC19 plasmid DNA. Therefore, we suggest that the increase in plasmid superhelicity in response to different environmental stimuli entails the appearance of cruciform structures. The use of the (dA-dT)n units of various lengths made it possible to estimate the superhelical density of the plasmid DNA in vivo.

Chemical probing of the homopurine.homopyrimidine tract in supercoiled DNA at single-nucleotide resolution

Local structure of the homopurine.homopyrimidine tract in a supercoiled plasmid pEJ4 was studied using chemical probes at single-nucleotide resolution. The conformation of the homopyrimidine strand was probed by osmium tetroxide, pyridine (Os,py) while that of the homopurine strand was tested by diethyl pyrocarbonate (DEPC), i.e. by probes reacting preferentially with single-stranded DNA. At weakly acidic pH values, a strong Os,py attack on three nucleotides at the centre of the (dC-dT)16 block and a weaker attack on two nucleotides at the end of the block were observed. DEPC modified adenines in the 5'-half of the homopurine strand. Os,py modification at the centre of the block corresponded to the loop of the hairpin formed by the homopyrimidine tract, while DEPC modification corresponded to the unstructured half of the homopurine strand in the model of protonated triplex H form of DNA.

A structural transition in d(AT)n.d(AT)n inserts within superhelical DNA

We have constructed plasmids carrying d(AT)n.d(AT)n inserts of different lengths. Two-dimensional gel electrophoresis patterns show that an increase in the negative superhelicity of these DNAs brings about a structural transition within the inserts, resulting in a reduction of the superhelical stress. However, this reduction corresponds to the expected values neither for cruciform nor the Z form. Those DNA topoisomers in which the structural transition had occurred proved to be specifically recognizable by single-strand-specific endonuclease S1, with the cleavage site situated at the centre of the insert. These data, as well as kinetic studies, suggest that the cloned d(AT)n.d(AT)n sequences adopt a cruciform rather than the Z-form structure. We discuss plausible reasons of the discrepancy between the observed superhelical stress release and that expected for the transition of the insert to the cruciform state.

The absence of cruciform structures from pAO3 plasmid DNA in vivo

We extracted pAO3 plasmid DNA from E. coli cells, having "frozen" the transition between cruciform and double-helical conformations in DNA. The characteristic feature of the DNA isolation procedure is that all steps were carried out at temperature between 0 and 4 C and no phenol deproteinization was used, since it has been discovered that phenol destabilizes cruciform structures in pAO3 DNA. Two-dimensional gel electrophoresis has revealed no cruciform structures in the pAO3 DNA preparations obtained this way, although the superhelical density of DNA was sufficient for them. Cruciform structures are absent from intracellular pAO3 DNA at all growth stages of the bacterial culture: stationary and logarithmic, and under the induction of pAO3 DNA replication in chloramphenicol-treated cells.