Pharmacokinetics of estradiol valerate and medroxyprogesterone acetate in different age groups of postmenopausal women

The impact of medroxyprogesterone acetate on lipid profiles in Women: A time and dose-response meta-analysis of randomized controlled trials

BACKGROUND

The effect of MPA on the lipid profile and CVD risk is still controversial; hence, this comprehensive dose-response meta-analysis of randomized controlled trials was conducted to assess the effect of MPA on lipid profiles in women.

METHODS

A comprehensive search was conducted in the following databases: Web of Science, Scopus, PubMed/Medline, and Embase, up to October 20, 2023. A random-effects meta-analysis approach based on the DerSimonian and Laird method was used to compute the combined estimates of the intervention's impact on the lipid profile.

RESULTS

35 eligible studies with 58 arms were included in our meta-analyses analysis. Combined effect sizes suggested a significant effect of MPA on total cholesterol (TC) levels (WMD: -3.43 mg/dL, 95 % CI: -5.38 to -1.48, p < 0.001), HDL-C levels (WMD: -3.34 mg/dL, 95 % CI: -3.77 to -2.91, p < 0.001), and triglyceride (TG) levels (WMD: -9.13 mg/dL, 95 % CI: -10.92 to -7.33, p < 0.001). The subgroup meta-analysis revealed a more substantial reduction in TC in studies with dosages > 2.5 mg/day (WMD: -4.10 mg/dL), mean participant age lower than 60 years (WMD: -3.80 mg/dL), mean BMI lower than 25 kg/m2 (WMD: -5.61 mg/dL), duration of intervention of 12 months or more (WMD: -3.98 mg/dL), and when the baseline TC value was equal to or greater than 200 mg/dL (WMD: -4.13 mg/dL).

CONCLUSIONS

The current meta-analysis showed a statistically significant decrease in TC, TG, and HDL-C levels and a non-significant increase in LDL-C levels after MPA administration in women.

Estradiol and Spironolactone Plasma Pharmacokinetics Among Brazilian Transgender Women Using HIV Pre-Exposure Prophylaxis: Analysis of Potential Interactions

BACKGROUND AND OBJECTIVE

An important barrier to HIV prevention among transgender women (TGW) is the concern that oral pre-exposure prophylaxis (PrEP) negatively affects the efficacy of feminizing hormone therapy (FHT). We aimed to assess the impact of PrEP on FHT pharmacokinetics (PK) among TGW from Brazil.

METHODS

We performed a drug-drug interaction sub-study among TGW enrolled in a daily oral PrEP demonstration study (PrEParadas, NCT03220152). Participants had a first PK assessment (PK1) 15 days after FHT (estradiol valerate 2-6 mg plus spironolactone 100-200 mg) initiation and then started PrEP (tenofovir disoproxil fumarate 300 mg/emtricitabine 200 mg). A second PK evaluation was performed 12 weeks later (PK2). Blood samples were collected prior and after the directly observed dosing (0, 0.5, 1, 2, 4, 6, 8, and 24 hours). Pharmacokinetic parameters of estradiol, spironolactone, and metabolites were estimated by non-compartmental analysis (Monolix 2021R2, Lixoft®) and compared as geometric mean ratios (GMRs, 90% confidence interval [CI]).

RESULTS

Among 19 TGW who completed the substudy, median age was 26 years (interquartile range: 23-27.5). Estradiol area under the plasma concentration-time curve (AUCτ) and trough concentrations did not differ between PK1 and PK2 evaluations (GMR [90% CI]: 0.89 [0.76-1.04] and 1.06 [0.94-1.20], respectively). Spironolactone and canrenone AUCτ were statistically lower at PK2 than PK1 (0.76 [0.65-0.89] and 0.85 [0.78-0.94], respectively). Canrenone maximum concentration was also lower at PK2 than PK1 (0.82 [0.74-0.91]).

CONCLUSION

Estradiol PK was not influenced by PrEP concomitant use. The small differences observed in some spironolactone and canrenone PK parameters should not prevent the concomitant use of estradiol-based FHT and PrEP.

TRIAL REGISTRATION

This trial (NCT03220152) was registered on July 18, 2017.

Methods and considerations for the use of hormonal contraceptives in rat models of neurobehavior

Hormonal contraceptives (HCs), prescribed to millions of women around the world, alter the ovarian hormonal cycle resulting in neurobehavioral changes in HC users. Human epidemiological and experimental data has characterized some of these effects with oftentimes conflicting or irreproducible results, reflecting a dearth of research considering different compositions, routes of administration, or time-courses of HC use. Non-human animal research can model these effects and help elucidate the underlying mechanisms by which different HCs modulate neurobehavioral outcomes. Still, animal models using HCs are not well-established. This may be because the pharmacological profile of HCs - including the metabolism, receptor binding affinity, and neuromodulatory effects - is dynamic and not always clearly translatable between animals and humans. The current review addresses these issues and provides basic methods and considerations for the use of HCs in animal models of neurobehavior to help advance the field of behavioral neuroendocrinology and inform decisions regarding to women's health.

Pharmacotherapeutic options for the treatment of menopausal symptoms

Introduction: Menopausal symptoms can be very overwhelming for women. Over the years, many pharmacotherapeutic options have been tested, and others are still being developed. Hormone therapy (HT) is the most efficient therapy for managing vasomotor symptoms and related disturbances. The term HT comprises estrogens and progestogens, androgens, tibolone, the tissue-selective estrogen complex (TSEC), a combination of bazedoxifene and conjugated estrogens, and the selective estrogen receptor modulators, such as ospemifene. Estrogens and progestogens and androgens may differ significantly for chemical structure and can be delivered through different routes, thereby displaying various pharmacological and clinical properties. Tibolone, TSEC and SERM also exhibit unique pharmacodynamics that can be exploited to obtain distinctive therapeutic effects. Non-hormonal options fall mainly into the selective serotonin reuptake inhibitor (SSRI) and selective noradrenergic reuptake inhibitor (SNRI), GABA-analogue drug classes.Areas covered: Herein, the authors describe the pharmacokinetics and pharmacodynamics of hormonal (androgens, estrogens, progestogens, tibolone, TSEC, SERMs) and non-hormonal (SSRIs, SNRIs, Gabapentin, Pregabalin, Oxybutynin, Neurokinin antagonists) treatments for menopausal symptoms and report essential clinical trial data in humans.Expert opinion: Patient tailoring of treatment is key to managing symptoms of menopause. Physicians must have in-depth knowledge of the pharmacology of compounds to tailor therapy to the individual patient's characteristics and needs.

Relationships between body mass index with oral estradiol dose and serum estradiol concentration in transgender adults undergoing feminising hormone therapy

AIM

Feminising hormone therapy with estradiol is used to align an individual's physical characteristics with their gender identity. Given considerable variations in doses of estradiol therapy administered as gender-affirming hormone therapy (GAHT), we aimed to assess if body mass index (BMI) correlated with estradiol dose/concentration and assess the correlation between estradiol dose and estradiol concentrations.

METHODS

In a retrospective cross-sectional study, we analysed transgender individuals attending a primary or secondary care clinic in Melbourne, Australia who were prescribed oral estradiol valerate for at least 6 months and had estradiol dose and concentration available. Estradiol concentration was measured by immunoassay. Outcomes were the correlation between estradiol dose and BMI, and estradiol dose and estradiol concentration.

RESULTS

Data were available for 259 individuals {median age 25.8 [interquartile range (IQR) 21.9, 33.5] years}. Median duration of estradiol therapy was 24 (15, 33) months. Median estradiol concentration was 328 (238, 434) pmol/l [89 (65, 118) pg/ml] on 6 (4, 8) mg estradiol valerate. Median BMI was 24.7 (21.8, 28.6) kg/m². There was a weak positive correlation between estradiol dose and estradiol concentration (r = 0.156, p = 0.012). There was no correlation between BMI and estradiol concentration achieved (r = -0.063, p = 0.413) or BMI and estradiol dose (r = 0.048, p = 0.536). Estradiol concentrations were within the target range recommended in consensus guidelines in 172 (66%) individuals.

CONCLUSION

Estradiol dose was only weakly correlated with estradiol concentration, suggesting significant interindividual variability. Prescription of estradiol dose should not be based upon an individual's BMI, which did not correlate with estradiol concentration achieved. In all, 66% of individuals achieved estradiol concentrations recommended in Australian consensus guidelines with a relatively high oral estradiol dose.

Reprint of "Use of medroxyprogesterone acetate for hormone therapy in postmenopausal women: Is it safe?"

Medroxyprogesterone acetate (MPA) has been in clinical use for over 30 years, and was generally considered to be safe until the results of long-term studies of postmenopausal hormone therapy (HT) using treatment with conjugated equine estrogens (CEE) combined with MPA and CEE alone suggested that MPA, and perhaps other progestogens, may play a role in the increased risk of breast cancer and cardiovascular diseases. This review examines critically the safety of MPA in terms of breast cancer and cardiovascular disease risk, and its effects on brain function. Research into mechanisms by which MPA might cause adverse effects in these areas, combined with the available clinical evidence, suggests a small increase in relative risk for breast cancer and stroke, and a decline in cognitive function, in older women using MPA with an estrogen for postmenopausal HT. However, short-term (less than 5 years) use of MPA with an estrogen in the years immediately after the onset of menopause for the management of vasomotor symptoms does not appear to be associated with any increased risk of these disorders.

Use of medroxyprogesterone acetate for hormone therapy in postmenopausal women: is it safe?

Medroxyprogesterone acetate (MPA) has been in clinical use for over 30 years, and was generally considered to be safe until the results of long-term studies of postmenopausal hormone therapy (HT) using treatment with conjugated equine estrogens (CEE) combined with MPA and CEE alone suggested that MPA, and perhaps other progestogens, may play a role in the increased risk of breast cancer and cardiovascular diseases. This review examines critically the safety of MPA in terms of breast cancer and cardiovascular disease risk, and its effects on brain function. Research into mechanisms by which MPA might cause adverse effects in these areas, combined with the available clinical evidence, suggests a small increase in relative risk for breast cancer and stroke, and a decline in cognitive function, in older women using MPA with an estrogen for postmenopausal HT. However, short-term (less than 5 years) use of MPA with an estrogen in the years immediately after the onset of menopause for the management of vasomotor symptoms does not appear to be associated with any increased risk of these disorders.

Reproducibility of proteomic profiles over 3 years in postmenopausal women not taking postmenopausal hormones

Most proteomics studies examine one blood specimen per participant; however, it is unknown how well measures at one time point reflect an individual's long-term proteome pattern. Therefore, we examined the stability of the proteome over 3 years in postmenopausal women not taking hormones for at least 3 months using surface-enhanced laser desorption and ionization time-of-flight mass spectrometry. Using the Nurses' Health Study blood cohort, we randomly selected 60 women from a subset providing 2 to 3 blood samples over 3 years. Four different protein chip surfaces/plasma fractions were examined: unfractionated plasma on a CM10 and H50 chip, pH >/= 9, plasma fraction on a CM10 chip, and the organic fraction on the H50 chip, all with a low- and high-energy transfer protocol. Participant and quality control samples were aligned to a reference sample and then peak intensity was assessed for all peaks identified in the reference sample. The average coefficient of variation (CV) of the peak intensity within conditions ranged from 16% (H50, organic, low protocol) to 63% (CM10, pH > or = 9, high protocol). Generally, the CV and mean peak intensity of the quality control samples were inversely correlated (median -0.48). The mean intraclass correlation (ICC) within conditions ranged from 0.37 (H50, unfractionated, low protocol) to 0.68 (CM10, unfractionated, high protocol). For a signal-to-noise cutoff of 2.0, we observed 334 peaks, of which 241 (72%) had an ICC of > or =0.40. Although we observed a large range of CVs and ICCs, sufficient numbers of peaks had reasonable ICCs to suggest that protein peak reproducibility over 3 years was reasonable among postmenopausal women not taking hormones.

Medroxyprogesterone Abrogates the Inhibitory Effects of Estradiol on Vascular Smooth Muscle Cells by Preventing Estradiol Metabolism

Sequential conversion of estradiol (E) to 2/4-hydroxyestradiols and 2-/4-methoxyestradiols (MEs) by CYP450s and catechol- O -methyltransferase, respectively, contributes to the inhibitory effects of E on smooth muscle cells (SMCs) via estrogen receptor–independent mechanisms. Because medroxyprogesterone (MPA) is a substrate for CYP450s, we hypothesized that MPA may abrogate the inhibitory effects of E by competing for CYP450s and inhibiting the formation of 2/4-hydroxyestradiols and MEs. To test this hypothesis, we investigated the effects of E on SMC number, DNA and collagen synthesis, and migration in the presence and absence of MPA. The inhibitory effects of E on cell number, DNA synthesis, collagen synthesis, and SMC migration were significantly abrogated by MPA. For example, E (0.1μmol/L) reduced cell number to 51±3.6% of control, and this inhibitory effect was attenuated to 87.5±2.9% by MPA (10 nmol/L). Treatment with MPA alone did not alter any SMC parameters, and the abrogatory effects of MPA were not blocked by RU486 (progesterone-receptor antagonist), nor did treatment of SMCs with MPA influence the expression of estrogen receptor-α or estrogen receptor-β. In SMCs and microsomal preparations, MPA inhibited the sequential conversion of E to 2–2/4-hydroxyestradiol and 2-ME. Moreover, as compared with microsomes treated with E alone, 2-ME formation was inhibited when SMCs were incubated with microsomal extracts incubated with E plus MPA. Our findings suggest that the inhibitory actions of MPA on the metabolism of E to 2/4-hydroxyestradiols and MEs may negate the cardiovascular protective actions of estradiol in postmenopausal women receiving estradiol therapy combined with administration of MPA.

The effect of conjugated equine oestrogen on diabetes incidence: the Women's Health Initiative randomised trial

AIMS/HYPOTHESIS

Recent clinical trials have found that the combination of conjugated equine oestrogen (CEO) and medroxyprogesterone has a protective effect on the incidence of type 2 diabetes. To determine the effect of CEO alone on the incidence of diabetes mellitus in postmenopausal women, we analysed the results of the Women's Health Initiative oestrogen-alone trial.

METHODS

The Women's Health Initiative is a randomised, double-masked trial comparing the effect of daily 0.625 mg CEO with placebo during 7.1 years of follow-up of 10,739 postmenopausal women who were aged 50-79 years and had previously had a hysterectomy. Diabetes incidence was ascertained by self-report of treatment with insulin or oral hypoglycaemic medication. Fasting glucose, insulin and lipoproteins were measured in an 8.6% random sample of study participants, at baseline and at 1, 3 and 6 years.

RESULTS

The cumulative incidence of treated diabetes was 8.3% in the oestrogen-alone group and 9.3% in the placebo group (hazard ratio 0.88, 95% CI 0.77-1.01, p=0.072). During the first year of follow-up, a significant fall in insulin resistance (homeostasis model assessment of insulin resistance) in actively treated women compared with the control subjects (Year 1 baseline between-group difference -0.53) was seen. However, there was no difference in insulin resistance at the 3- or 6-year follow-up.

CONCLUSIONS/INTERPRETATION

Postmenopausal therapy with oestrogen alone may reduce the incidence of treated diabetes. The effect is smaller than that seen with oestrogen plus progestin. CEO should not, however, be used with the intention of preventing diabetes, as its well-described adverse effects preclude long-term use for primary prevention.

Pharmacology of estrogens and progestogens: influence of different routes of administration

This review comprises the pharmacokinetics and pharmacodynamics of natural and synthetic estrogens and progestogens used in contraception and therapy, with special consideration of hormone replacement therapy. The paper describes the mechanisms of action, the relation between structure and hormonal activity, differences in hormonal pattern and potency, peculiarities in the properties of certain steroids, tissue-specific effects, and the metabolism of the available estrogens and progestogens. The influence of the route of administration on pharmacokinetics, hormonal activity and metabolism is presented, and the effects of oral and transdermal treatment with estrogens on tissues, clinical and serum parameters are compared. The effects of oral, transdermal (patch and gel), intranasal, sublingual, buccal, vaginal, subcutaneous and intramuscular administration of estrogens, as well as of oral, vaginal, transdermal, intranasal, buccal, intramuscular and intrauterine application of progestogens are discussed. The various types of progestogens, their receptor interaction, hormonal pattern and the hormonal activity of certain metabolites are described in detail. The structural formulae, serum concentrations, binding affinities to steroid receptors and serum binding globulins, and the relative potencies of the available estrogens and progestins are presented. Differences in the tissue-specific effects of the various compounds and regimens and their potential implications with the risks and benefits of hormone replacement therapy are discussed.