Progestational and androgenic receptor binding affinities and in vivo activities of norgestimate and other progestins

A mouse model of oral contraceptive exposure: Depression, motivation, and the stress response

Hormonal contraceptives, including oral contraceptives (OCs), regulate hormonal cycles and broadly affect physiological processes, including stress responsivity. Whereas many users describe overall improved mood, up to 10 % of OC users experience adverse effects, including depression and anxiety. Given the link between regulation of hypothalamic-pituitary-adrenal (HPA) axis, stress exposure, and risk for depression, it is likely that OC-effects on stress mediate increased risk or increased resilience to these disorders. In this study, we developed and characterized a tractable mouse model of OC exposure with which to identify the mechanisms underlying OC modulation of brain, behavior, and mood. Specifically, we aimed to determine whether translationally relevant doses of OC-hormones in mice mimic changes in stress responsivity observed in humans taking OCs and describe behavioral changes during OC exposure. Young adult female C57Bl/6 N mice received daily ethinyl estradiol (EE) and levonorgestrel (LVNG) in 10 % sucrose, EE and drospirenone (DRSP) in 10 % sucrose, or 10 % sucrose alone. Translationally relevant doses of EE + LVNG-exposure, but not EE + DRSP, suppressed the acute stress response, consistent with effects observed in human OC users. EE + LVNG caused a specific anhedonia-like effect, without broad changes in stress-coping behavior, other depression-like behaviors, or anxiety-like behaviors. The suppression of regular estrous cycling, together with the blunting of the corticosterone response to acute stress, demonstrate the utility of this model for future studies to identify the mechanisms underlying OC interactions with stress, motivation, and risk for depression.

SYF2 suppression mitigates neurodegeneration in models of diverse forms of ALS

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease caused by many diverse genetic etiologies. Although therapeutics that specifically target causal mutations may rescue individual types of ALS, such approaches cannot treat most patients since they have unknown genetic etiology. Thus, there is a critical need for therapeutic strategies that rescue multiple forms of ALS. Here, we combine phenotypic chemical screening on a diverse cohort of ALS patient-derived neurons with bioinformatic analysis of large chemical and genetic perturbational datasets to identify broadly effective genetic targets for ALS. We show that suppressing the gene-encoding, spliceosome-associated factor SYF2 alleviates TDP-43 aggregation and mislocalization, improves TDP-43 activity, and rescues C9ORF72 and causes sporadic ALS neuron survival. Moreover, Syf2 suppression ameliorates neurodegeneration, neuromuscular junction loss, and motor dysfunction in TDP-43 mice. Thus, suppression of spliceosome-associated factors such as SYF2 may be a broadly effective therapeutic approach for ALS.

Hormonal contraceptives, stress, and the brain: The critical need for animal models

Hormonal contraceptives are among the most important health and economic developments in the 20thCentury, providing unprecedented reproductive control and a range of health benefits including decreased premenstrual symptoms and protections against various cancers. Hormonal contraceptives modulate neural function and stress responsivity. These changes are usually innocuous or even beneficial, including their effects onmood. However, in approximately 4-10% of users, or up to 30 million people at any given time, hormonal contraceptives trigger depression or anxiety symptoms. How hormonal contraceptives contribute to these responses and who is at risk for adverse outcomes remain unknown. In this paper, we discussstudies of hormonal contraceptive use in humans and describe the ways in which laboratory animal models of contraceptive hormone exposure will be an essential tool for expanding findings to understand the precise mechanisms by which hormonal contraceptives influence the brain, stress responses, and depression risk.

Effects of oral contraceptives on spatial cognition depend on pharmacological properties and phase of the contraceptive cycle

The central nervous system effects of oral contraceptives (OCs) are not well-documented. In a set of 3 studies, we investigated a specific cognitive function, mental rotation, in healthy women currently using OCs for contraceptive purposes (n = 201) and in medication-free controls not using OCs (n = 44). Mental rotation was measured using a well-standardized and extensively validated psychometric test, the Vandenberg Mental Rotations Test (MRT). In an initial study (Study 1), current OC users (n = 63) were tested during the active or inactive phases of the contraceptive cycle in a parallel-groups design. Studies 2 and 3 were based on an archival dataset (n = 201 current OC users) that consisted of data on the MRT collected in real-time over a 30-year period and compiled for purposes of the present work. The OCs were combined formulations containing ethinyl estradiol (10-35 ug/day) plus a synthetic progestin. All 4 families of synthetic progestins historically used in OCs were represented in the dataset. Cognitive performance was evaluated during either active OC use ('active phase') or during the washout week of the contraceptive cycle ('inactive phase') when OC steroids are not used. The results showed a significant phase-of-cycle (POC) effect. Accuracy on the MRT was mildly diminished during the active phase of OC use, while scores on verbal fluency and speeded motor tasks were modestly improved. The POC effect was most evident in women using OCs that contained first- or second-generation progestins (the estrane family of progestins or OCs containing levonorgestrel), but not in women using OCs containing recently developed progestins and lower doses of ethinyl estradiol. Using independently established ratings of the estrogenic, androgenic, and progestogenic intensities of the different OC formulations, each brand of OC was classified according to its distinct endocrine profile. Multiple regression revealed that the effects of OC use on the MRT could be predicted based on the estrogenic strength of the contraceptives used. Estrogenic potency, not androgenic or anti-androgenic effects of the OC pill, may underlie the effects of OC usage on spatial cognition.

Determining the Exposure Threshold for Levonorgestrel Efficacy Using an Integrated Model Based Meta-Analysis Approach

Combined oral contraceptive pills are the most commonly used hormonal contraceptives for the prevention of unintended pregnancies in United States. They consist of a progestin (e.g., levonorgestrel (LNG)) and an estrogen component, typically ethinyl estradiol (EE). In addition to adherence issues, drug-drug interactions (DDIs) and obesity (women with body mass index (BMI) ≥ 30 kg/m² ) are prime suspects for decreased LNG efficacy. Therefore, we developed an integrated physiologically-based pharmacokinetic modeling and model-based meta-analysis approach to determine LNG's efficacy threshold concentrations and to evaluate the impact of DDIs and obesity on the efficacy of LNG-containing hormonal contraceptives (HCs). Based on this approach, co-administration of strong CYP3A4 inducers and LNG-containing HCs (LNG150: LNG 150 µg + EE 30 µg and LNG100: LNG 100 µg + EE 20 µg) resulted in a predicted clinically relevant decrease of LNG plasma exposure (women with BMI < 25 kg/m² : 50-65%; obese women: 70-75%). Following administration of LNG150 or LNG100 in the presence of a CYP3A4 inducer, there was an increase in mean Pearl Index of 1.2-1.30 and 1.80-2.10, respectively, in women with BMI < 25 kg/m² (incidence rate ratios (IRRs): 1.7-2.2), whereas it ranged from 1.6-1.80 and 2.40-2.85 in obese women (IRR: 2.2-3.0), respectively. Our results suggest that the use of backup or alternate methods of contraception is not necessarily required for oral LNG + EE formulations except within circumstances of both obesity and strong CYP3A4 inducer concomitance following administration of LNG100.

The new low-dose transdermal contraceptive system (Twirla®): results from preclinical and Phase III trials

A new low-dose, once-a-week contraceptive transdermal delivery system (TDS) with 2.3-mg ethinyl estradiol (EE) and 2.6-mg levonorgestrel (LNG; Twirla^®) has recently been approved by the US FDA for contraception of women with BMI <30 kg/m². The rationale for developing this new patch, the preclinical study results and the results from two innovative Phase III clinical trials demonstrate that this patch has an acceptable Pearl index (4.3%) for its indicated users and has safety and tolerability comparable to other similar dose oral combined hormonal contraceptives. This new TDS provides an improvement over the existing TDS products, with significantly lower steady-state estrogen exposure, a level equal to that with 30-µg EE containing oral contraceptives.

Pharmacokinetics, metabolism and serum concentrations of progestins used in contraception

Many different forms of hormonal contraception are used by millions of women worldwide. These contraceptives differ in the dose and type of synthetic progestogenic compound (progestin) used, as well as the route of administration and whether or not they contain estrogenic compounds. There is an increasing awareness that different forms of contraception and different progestins have different side-effect profiles, in particular their cardiovascular effects, effects on reproductive cancers and susceptibility to infectious diseases. There is a need to develop new methods to suit different needs and with minimal risks, especially in under-resourced areas. This requires a better understanding of the pharmacokinetics, metabolism, serum and tissue concentrations of progestins used in contraception as well as the biological activities of progestins and their metabolites via steroid receptors. Here we review the current knowledge on these topics and identify the research gaps. We show that there is a paucity of research on most of these topics for most progestins. We find that major impediments to clear conclusions on these topics include a lack of standardized methodologies, comparisons between non-parallel clinical studies and variability of data on serum concentrations between and within studies. The latter is most likely due, at least in part, to differences in intrinsic characteristics of participants. The review highlights the importance of insight on these topics in order to provide the best contraceptive options to women with minimal risks.

The paradigm of norgestimate: a third-generation testosterone-derivative progestin with a peripheral anti-androgenic activity and the lowest risk of venous thromboembolism

INTRODUCTION

Norgestimate (NGM) is a testosterone derivative with peculiar receptor activities.

AREAS COVERED

This is a narrative review of the available data on the pharmacotherapy of NGM in combined hormonal contraceptives (CHCs) in terms of contraceptive efficacy, venous thromboembolism (VTE) risk, safety, tolerability and bleeding patterns. A comprehensive literature review was conducted in August 2020 using PubMed with the keyword 'norgestimate'.

EXPERT OPINION

NGM shows a mild estrogenic activity associated with anti-mineralocorticoid and anti-androgenic properties, largely responsible for the cardiovascular safety profile. The anti-androgenic property depends on the androgen receptor (AR) nuclear translocation (AR trafficking and its subnuclear distribution), the inhibition of 5α-reductase activity (it possesses higher activity compared to other available progestins), and the increase on sexual hormone binding globulin (SHBG) levels if combined with an estrogenic counterpart. NGM is one of the molecules that best modulates the power of ethinyl-estradiol on the thromboembolic risk, being associated with the lowest VTE risk between different CHCs. NGM has the advantage of retaining peripheral anti-androgenic activity, demonstrated by the impact on lipid and glucose metabolism, and it should be preferred if compared with other similar progestins of the same class of risk which are much more androgenic, such as levonorgestrel.

Ethinyl estradiol and levonorgestrel alter cognition and anxiety in rats concurrent with a decrease in tyrosine hydroxylase expression in the locus coeruleus and brain-derived neurotrophic factor expression in the hippocampus

In the United States, more than ten million women use contraceptive hormones. Ethinyl estradiol and levonorgestrel have been mainstay contraceptive hormones for the last four decades. Surprisingly, there is scant information regarding their action on the central nervous system and behavior. Intact female rats received three weeks of subcutaneous ethinyl estradiol (10 or 30μg/rat/day), levonorgestrel (20 or 60μg/rat/day), a combination of both (10/20μg/rat/day and 30/60μg/rat/day), or vehicle. Subsequently, the rats were tested in three versions of the novel object recognition test to assess learning and memory, and a battery of tests for anxiety-like behavior. Serum estradiol and ovarian weights were measured. All treatment groups exhibited low endogenous 17β-estradiol levels at the time of testing. Dose-dependent effects of drug treatment manifested in both cognitive and anxiety tests. All low dose drugs decreased anxiety-like behavior and impaired performance on novel object recognition. In contrast, the high dose ethinyl estradiol increased anxiety-like behavior and improved performance in cognitive testing. In the cell molecular analyses, low doses of all drugs induced a decrease in tyrosine hydroxylase mRNA and protein in the locus coeruleus. At the same time, low doses of ethinyl estradiol and ethinyl estradiol/levonorgestrel increased galanin protein in this structure. Consistent with the findings above, the low dose treatments of ethinyl estradiol and combination ethinyl estradiol/levonorgestrel reduced brain-derived neurotrophic factor mRNA in the hippocampus. These effects of ethinyl estradiol 10μg alone and in combination with levonorgestrel 20μg suggest a diminution of norepinephrine input into the hippocampus resulting in a decline in learning and memory.

A prospective, randomized, pharmacodynamic study of quick-starting a desogestrel progestin-only pill following ulipristal acetate for emergency contraception

STUDY QUESTION

Is there a pharmacodynamic interaction between ulipristal acetate (UPA) 30 mg for emergency contraception and a daily progestin-only contraceptive pill, desogestrel (DSG) 0.75 mg, when initiated the next day?

SUMMARY ANSWER

In this study, DSG impaired the ability of UPA to delay ovulation, but UPA had little impact on the onset of contraceptive effects due to DSG.

WHAT IS KNOWN ALREADY

UPA is a progesterone receptor modulator used for emergency contraceptive (EC) at the dose of 30 mg. UPA delays ovulation by at least 5 days when administered in the mid to late follicular phase. In theory, potent progestins could reactivate progesterone signaling that leads to follicle rupture, thereby impacting the effectiveness of UPA as EC. In addition, UPA could alter the onset of the contraceptive effect of progestin-containing contraceptives started immediately after UPA.

STUDY DESIGN, SIZE, DURATION

A single-blind (for observer), placebo-controlled, partial crossover study was conducted in two sites [Dominican Republic (DR) and the Netherlands (NDL)] over 11 months from October 2012 to September 2013. Healthy female volunteers participated in two of the three treatment cycles separated by a washout cycle. Treatment combinations studied were as follows: (i) a single 30 mg dose of UPA followed by 75 µg per day DSG for 20 days, (ii) a single 30 mg dose of UPA followed by 20 days of placebo matching that of DSG (PLB2) or (iii) one tablet of placebo-matching UPA (PLB1) followed by 75 µg per day DSG for 20 days. Participants were randomized to one of the three treatment sequences (UPA + DSG/UPA + PLB2, PLB1 + DSG/UPA + DSG and UPA + PLB2/PLB1 + DSG) when a lead follicle was ≥ 14 to <16 mm diameter on transvaginal ultrasound imaging (TVU).

PARTICIPANTS/MATERIAL, SETTING, METHODS

A total of 71 women were included, and 49 were randomized to a first treatment combination of the three period sequences (20 in the DR and 29 in the NDL); 41 of the 49 continued and completed two treatment combinations (20 in the DR and 21 in the NDL).

MAIN RESULTS AND THE ROLE OF CHANCE

Initiating DSG treatment the day after UPA significantly reduced the ovulation delaying effect of UPA (P = 0.0054). While ovulation occurred in only one of the 29 UPA-only cycles (3%) in the first 5 days, it occurred in 13 of the 29 (45%) UPA + DSG cycles.

LIMITATIONS, REASONS FOR CAUTION

This was a small, descriptive, pharmacodynamic study in which some findings differed by study site. Distinguishing between a cystic corpus luteum and a luteinized unruptured follicle (LUF) by TVU was difficult in some cases; however, the investigators reached consensus, when the study was still blinded, regarding ovulation based on hormone levels and careful review of daily TVU images.

WIDER IMPLICATIONS OF THE FINDINGS

Initiating the use of a DSG progestin-only pill (POP) immediately after UPA reduces the ability of UPA to delay ovulation and thus may decrease its efficacy as EC. If starting a DSG POP after using UPA for EC, and possibly any progestin-only method, consideration should be given to delaying for at least 5 days after UPA intake in order to preserve the ovulation delaying effects of UPA.

Quantification of 17-desacetyl norgestimate in human plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and its application to bioequivalence study

A rapid and sensitive ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed and validated for the estimation of 17-desacetyl norgestimate in human plasma using solid-phase extraction technique. 17-desacetyl norgestimate D6 was used as the internal standard. Simple gradient chromatographic conditions and mass spectrometric detection enabled accurate and precise measurement of 17-desacetyl norgestimate at sub-picogram levels. The proposed method was validated for a linear range of 20–5000 pg/mL with a correlation coefficient ≥0.9988. The intra-run and inter-run precision and accuracy were within 10%. The overall recoveries for 17-desacetyl norgestimate and 17-desacetyl norgestimate D6 were 96.30% and 93.90%, respectively. The total run time was 4.5 min. The developed method was applied for the determination of the pharmacokinetic parameters of 17-desacetyl norgestimate following a single oral administration of a norgestimate and ethinyl estradiol 0.250 mg/0.035 mg tablets in 35 healthy female volunteers.

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Simple and rapid estimation of norgestimate metabolite in human plasma.

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Sensitive method for 17-desetyl norgestimate estimation with limit of quantification 20 pg/mL.

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Better cleanup using solid phase extraction method.

Potency of progestogens used in hormonal therapy: toward understanding differential actions

Progestogens are widely used in contraception and in hormone therapy. Biochemical and molecular biological evidence suggests that progestogens differ widely in their affinities and transcriptional effects via different steroid receptors, and hence cannot be considered as a single class of compounds. Consistent with these observations, recent clinical evidence suggests that, despite their similar progestogenic actions, these differences underlie different side-effect profiles for cardiovascular disease and susceptibility to infectious diseases. However, choice of progestogen for maximal benefit and minimal side-effects is hampered by insufficient comparative clinical and molecular studies to understand their relative mechanisms of action, as well as their relative potencies for different assays and clinical effects. This review evaluates the usage, meaning and significance of the terms affinity, potency and efficacy in different models systems, with a view to improved understanding of their physiological and pharmacological significance. This article is part of a Special Issue entitled 'Menopause'.

Functional role of progestin and the progesterone receptor in the suppression of spermatogenesis in rodents

Synthetic progestins such as levonorgestrel (LNG) are used in combination with testosterone (T) in male contraceptive clinical trials to suppress gonadotropins secretion, but whether progestins have additional direct effects on the testis are not known. This study aimed to examine the effect of a potent progestin, (LNG), alone or in combination with testosterone (T) on spermatogenesis in adult rats, and to evaluate the functional role of the progesterone receptors (PRs) in the testis. In comparison with a low dose of LNG treatment in adult rats for 4 weeks, T and T + LNG treatment decreased testicular sperm count to 64.1 and 40.2% of control levels respectively. LNG induced germ cell apoptosis at stages I-IV and XII-XIV; T increased apoptosis at stages VII-VIII; LNG + T treatment induced greater germ cell apoptosis at a wider range of seminiferous epithelial stages. RT-PCR and Western Blots showed that PR was present in testes and up-regulated during suppression of spermatogenesis induced by testicular hormonal deprivation. PR knockout (PRKO) mice had larger testes, greater sperm production, increased numbers of Sertoli and Leydig cells. Suppression of gonadotropin and intratesticular T by GnRH-antagonist treatment induced PR promoter driven LacZ expression in Leydig cells of PRKO mice. This suggests that GnRH-antagonist treatment while inducing germ cell apoptosis also up-regulates PR. We conclude that (i) LNG + T induced greater suppression of spermatogenesis through increase in germ cell apoptosis involving a wider range of seminiferous epithelial stages than either treatment alone, (ii) up-regulation of PR was associated with inhibition of spermatogenesis, (iii) PR knockout mice showed increased sperm production suggesting that testicular PR activated events play a physiological and pharmacological inhibitory role in the testis. These data support the hypothesis that in addition to its known suppressive effects on gonadotropins, progestins may have direct inhibitory actions on the testis.

BAY 1002670: a novel, highly potent and selective progesterone receptor modulator for gynaecological therapies

STUDY QUESTION

Does the novel progesterone receptor (PR) modulator BAY 1002670, based on its preclinical pharmacological profile, offer a potential novel treatment option for uterine fibroids?

SUMMARY ANSWER

The newly synthesized BAY1002670 has proved to be a very potent, highly selective PR modulator in all in vitro and in vivo pharmacodynamics assays performed: it exhibits marked efficacy in an innovative humanized fibroid disease model, suggesting BAY 1002670 to be a very promising treatment option for uterine fibroids.

WHAT IS KNOWN ALREADY

PR inhibiting ligands have shown clinical utility in a range of potential indications and applications. Despite the emergence of the first PR antagonist >30 years ago, no agent of this compound class has been authorized in any indication for long-term application. Among other reasons, suboptimal selectivity and safety profiles of previous candidates have led to discontinuation and modification of development programmes.

STUDY, DESIGN, SIZE, DURATION

The preclinical studies include relevant in vitro and in vivo assays to clarify the properties of the PR modulator BAY 1002670 as well as a fibroid xenograft study to show directly the efficacy of BAY 1002670 on the human target tissue.

PARTICIPANTS/MATERIAL, SETTING, METHODS

BAY 1002670 was tested for binding and transactivational activity towards different human steroid receptors. Activity of the compound in the corresponding in vivo models (rat, rabbit) was assessed. Furthermore, BAY 1002670 was tested in a disease model for uterine fibroids utilizing primary human tumour tissues as xenograft in immunodeficient mice treated with estradiol (E2) and progesterone (P).

MAIN RESULT AND THE ROLE OF CHANCE

BAY1002670 in subnanomolar concentrations exhibits a highly selective binding profile and antagonistic activity for the PR. These properties are also reflected in its action in two progesterone-dependent animal models that assess the termination of pregnancy and endometrial transformation. Favourable selectivity towards other nuclear hormone receptors was demonstrated. No in vivo activity was found at the glucocorticoid, estrogenic and mineralocorticoid receptors with only weak anti-androgenic activity. In a human fibroid xenograft model BAY 1002670 showed a marked dose-dependent reduction of fibroid tumour weight gain of 95% at a dose of 3 mg/kg/day (P < 0.005).

LIMITATIONS AND REASON FOR CAUTION

Selectivity and potency of BAY 1002670 have only been determined in vitro and in animal models so far.

WIDER IMPLICATIONS OF THE FINDING

The PR modulator BAY 1002670 might offer a treatment option not only for uterine fibroids but also for other gynaecological indications.

STUDY FUNDING/COMPETING INTEREST

The studies took place at Bayer Pharma AG. All authors are employees of Bayer Pharma AG. No external funding declared.

Progestogens used in postmenopausal hormone therapy: differences in their pharmacological properties, intracellular actions, and clinical effects

The safety of progestogens as a class has come under increased scrutiny after the publication of data from the Women's Health Initiative trial, particularly with respect to breast cancer and cardiovascular disease risk, despite the fact that only one progestogen, medroxyprogesterone acetate, was used in this study. Inconsistency in nomenclature has also caused confusion between synthetic progestogens, defined here by the term progestin, and natural progesterone. Although all progestogens by definition have progestational activity, they also have a divergent range of other properties that can translate to very different clinical effects. Endometrial protection is the primary reason for prescribing a progestogen concomitantly with postmenopausal estrogen therapy in women with a uterus, but several progestogens are known to have a range of other potentially beneficial effects, for example on the nervous and cardiovascular systems. Because women remain suspicious of the progestogen component of postmenopausal hormone therapy in the light of the Women's Health Initiative trial, practitioners should not ignore the potential benefits to their patients of some progestogens by considering them to be a single pharmacological class. There is a lack of understanding of the differences between progestins and progesterone and between individual progestins differing in their effects on the cardiovascular and nervous systems, the breast, and bone. This review elucidates the differences between the substantial number of individual progestogens employed in postmenopausal hormone therapy, including both progestins and progesterone. We conclude that these differences in chemical structure, metabolism, pharmacokinetics, affinity, potency, and efficacy via steroid receptors, intracellular action, and biological and clinical effects confirm the absence of a class effect of progestogens.

Occurrence, fate and removal of synthetic oral contraceptives (SOCs) in the natural environment: a review

Synthetic oral contraceptives (SOCs) are a group of compounds with progestagenic and/or androgenic activities, with some also possessing estrogenic activities. Recent research has documented that some of these emerging contaminants have adverse effects on aquatic organisms at very low concentrations. To facilitate the evaluation of their latent risks, published works on their occurrence and fate in the environment are reviewed. Androgenic/progestagenic relative potencies or relative binding affinity of these SOCs as well as their physicochemical properties and toxicity are summarized. Appropriate analytical methods are outlined for various environmental sample types, including methods of sample preparation and limit of detection/quantification (LOD/LOQ). Finally results on their occurrence and fate in wastewater treatment plants (WWTPs) and other environments are critically examined.

New-D-homoandrost-4,6-diene derivatives as potent progesterone receptor antagonist

The aim of this study was to synthesize three different D-homoandrostadiene derivatives (2-4) and study their biological activity. We carried out in vivo and in vitro experiments using female cycling mice, which were synchronized for estrus with luteinizing hormone-releasing hormone (LHRH) and injected with the steroidal compounds. It was also determined the binding of these compounds to the progesterone receptors (PR). Since these steroids have a new D-homoandrostandienone skeleton in their molecular structure, it was of interest also to study their binding to the androgen receptors (AR). After LHRH treatment, the mice of the control group showed the presence of 14+/-4 corpus lutea in the ovary whereas the animals treated with steroids 2-4, with RBAs of 100%, exhibited 11+/-7, 12+/-2, and 10+/-4 respectively. As a result of this study, it is evident that these steroids did not inhibit the ovulation in these animals. The uterus of the control group, showed the typical progestational activity with an enlarged endometrial thickness with a secretory activity. However, the endometrium of the mice treated with steroids 2-4 did not show an enlargement of the endometrium and no secretory activity could be detected. This fact indicates that compounds 2-4 had antagonistic activity in this tissue. The overall data show that steroids 2-4 are antagonists of the PR. However, they do not bind to the AR. These results also demonstrate that 2-4 have an antiprogestational activity in vivo, but do not decrease the number of corpus lutea in the ovary of mice treated with LHRH.

Synthesis and biological effect of halogen substituted phenyl acetic acid derivatives of progesterone as potent progesterone receptor antagonists

In this paper, we report the relative binding affinities to the progesterone receptor (PR) of several progesterone derivatives containing an acetoxyphenyl substituent at C-17 and their structure-bioactivity relationship. The inhibitory effect to ovulation as well as their function as interrupters of endometrial maturation is also described. The biological activity of the novel steroids was determined in vivo and in vitro experiments using female cycling mice, which were synchronized for estrus with luteinizing hormone-releasing hormone (LHRH) and injected with the steroidal compounds. The cytosol used for the determination of the PR, was obtained from the uteri of adult estrogen-primed rabbits and the androgen (AR), mineralocorticoid (MR) and glucocorticoid (GR) receptors were determined in the cytosolic fractions from the prostate of castrated rats and from the kidneys and livers of adenalectomized male rats. We evaluated six related steroidal compounds 8a-8f differing in the nature of the 17alpha ester side chain for the inhibition of [3H] R5020 binding to the PR. The IC50 values for the displacement of [3H] R5020 binding to the PR and its relative binding affinities (RBAs) were determined. Progesterone and R5020 had similar IC(50) values; steroids 8a, 8f and 8c bind to the progesterone receptor with RBAs of 100%, whereas 8e, 8b and 8d have RBA values <100%. These data indicate that there is a relationship between the structure of these steroids and their binding activity to the progesterone receptors. Having demonstrated in this study that steroids 8a-8f bind to the PR, we also evaluated the receptor's selectivity, since some progesterone derivatives bind to AR, MR, GR receptors. We demonstrated that the tested steroids did not bind to the AR, MR, GR, since none of the steroids inhibited the labeled mibolerone, aldosterone or dexamethasone binding to the AR, MR or GR, respectively. These results show that the novel compounds have certain selectivity for the PR. After LHRH treatment, the mice of the control group showed the presence of ova in the oviduct, whereas the animals treated with steroids 8a, 8f, 8e and 8c with RBAs of 92-100%, did not exhibit any ovum in the oviducts. As a result of this study, it is evident that the novel steroids 8a, 8f, 8e and 8c inhibited the ovulation in these animals at dose of 0.22 mg/kg. After the treatment with LHRH, the uterus of the control group showed the typical progestational activity with an enlarged endometrial thickness with secretory activity. However, the endometrium of the mice treated with steroids 8a, 8f, 8e and 8c (with RBAs of 92-100%) neither did show any enlargement of the endometrium, nor a secretory activity could be detected. The diameter of the uterus was also significantly reduced compared to those of the control group, thus indicating that compounds 8a, 8f, 8e and 8c had antagonistic activity in this tissue. The overall data showed that steroids 8a, 8f, 8e and 8c have a high and selective binding activity to the PR. Furthermore there is a relationship between the structure of these steroids and their binding activity, since the presence of fluorine atom in meta position in the acetoxyphenyl substituent at C-17, improved the binding activity as compared to that for the ortho and para positions. These data also demonstrated that 8a-8f have an anti-progestational activity in vivo, and therefore they have better characteristics than the compounds previously reported.

The influence of oral contraceptives on athletic performance in female athletes

It is now estimated that the prevalence of oral contraceptive use in athletic women matches that of women in the general population. The oral contraceptive pill (OCP) reduces cycle-length variability and provides a consistent 28-day cycle by controlling concentrations of endogenous sex hormones. The OCP is administered in three different forms that differ widely in chemical constitution and concomitant effects on the human body. As fluctuation in sex steroids are believed to be a possible causal factor in performance and exercise capacity, it is imperative to understand the effect of administering the various types of OCP on women. However, the research into oral contraceptives and exercise performance is not consistent. The type of OCP administered (monophasic, biphasic or triphasic), as well as the type and dose of estrogen and progestogen within, will have varying effects on exercise. To date, research in the area of oral contraceptives and exercise capacity is sparse and much has been plagued by poor research design, methodology and small sample size. It is clear from the research to date that more randomised clinical trials are urgently required to assess the array of OCP formulations currently available to women and their concomitant effect on health and exercise capacity. Therefore, the purpose of this article is to critically appraise the literature to date and to provide a current review of the physiological scientific knowledge base in relation to the OCP and exercise performance. In addition, methodological control, design and conduct will be considered with future areas of research highlighted.

Androgenicity of the progestin in oral contraceptives does not affect maximal leg strength

PURPOSE

This study was conducted to examine androgenicity of the progestin in oral contraceptive pills and its effect on maximal leg strength in females.

METHODS

Twelve participants who were using a monophasic pill containing 30 microg ethinylestradiol plus either 150 microg levonorgestrel (LEV) or 250 microg norgestimate (NOR) for at least the last 6 months were recruited (mean+/-SEM; LEV: age, 19.8+/-0.3 years; stature, 1.67+/-0.17 m; mass, 65.9+/-1.9 kg; NOR: age, 20.6+/-0.2 years; stature, 1.65+/-0.17 m; mass, 64.6+/-2.4 kg). Three maximal isokinetic extension and flexion tests were performed on three occasions (Days 3-6, 11-14 and 18-21 of the pill cycle) to assess peak extension and peak flexion torque (in Newton meters).

RESULTS

No significant (p>.05) differences were found in the LEV and NOR groups in peak extension torque (F=0.719; p=.416) or peak flexion torque (F=0.291, p=.601) throughout the pill cycle and between groups.

CONCLUSION

In this small study, the androgenicity of the progestin in the contraceptive pill had no significant association with maximal strength in these female athletes.

Polycystic ovary syndrome, oral contraceptives and metabolic issues: new perspectives and a unifying hypothesis

In the chronic treatment of polycystic ovary syndrome (PCOS), oral contraceptive pills (OCPs) are commonly used to induce regular menses, protect the endometrium and ameliorate androgenic symptoms. However, the long-term safety of OCP use in PCOS has not been established, and the literature reveals conflicting data concerning the metabolic effects of OCPs in this patient population, with outcomes ranging from improvement of glucose tolerance to the development of frank diabetes. This article presents new perspectives and a unifying hypothesis concerning the effects of OCPs on carbohydrate metabolism in PCOS and attempts to explain the divergent findings in published reports.

Oral contraceptives and mood in women with and without premenstrual dysphoria: a theoretical model

Despite numerous studies on the topic, there is no consensus to date on the effects of oral contraceptives on mood or the mechanism(s) by which they exert these effects. This review article presents a theoretical model to explain the way in which oral contraceptives may affect mood. Specifically, it is argued that progestins exert differential effects on endogenous levels of neurosteroids, thereby altering mood. After providing an overview of the effects of estrogen, progesterone, and progesterone's metabolites on cortical excitability and the role of neurosteroids in depression and premenstrual dysphoria, this article reviews the research that has been conducted on the relationship between oral contraceptives and neurosteroids. Finally, suggestions for future research are made with the dual aim of improving existing studies on the relationship between oral contraceptives and mood and further investigating the possibility that fluctuations in neurosteroid levels are responsible for the effects of oral contraceptives on mood.

A multicentre study investigating subcutaneous etonogestrel implants with injectable testosterone decanoate as a potential long-acting male contraceptive

BACKGROUND

The combination of etonogestrel implants with injectable testosterone decanoate was investigated as a potential male contraceptive.

METHODS

One hundred and thirty subjects were randomly assigned to three treatment groups, all receiving two etonogestrel rods (204 mg etonogestrel) and 400 mg testosterone decanoate either every 4 weeks (group I, n = 42), or every 6 weeks (group II, n = 51) or 600 mg testosterone decanoate every 6 weeks (group III, n = 37) for a treatment period of 48 weeks.

RESULTS

One hundred and ten men completed 48 weeks of treatment. Sperm concentrations of <1 x 10(6)/ml were achieved in 90% (group I), 82% (group II) and 89% (group III) of subjects by week 24. Suppression was slower in group II, which also demonstrated more frequent escape from gonadotrophin suppression than groups I and III. Peak testosterone concentrations remained in the normal range throughout in all groups. Mean trough testosterone concentrations were initially subphysiological but increased into the normal range during treatment. Mean haemoglobin levels increased in group I, and a non-significant increase in weight and decline in high-density lipoprotein cholesterol was observed in all groups. Fourteen subjects discontinued treatment due to adverse events.

CONCLUSIONS

Subcutaneous etonogestrel implants in combination with injectable testosterone decanoate resulted in profound suppression of spermatogenesis that could be maintained for up to 1 year. Efficacy of suppression was less in group II, probably due to inadequate testosterone dosage. This combination has potential as a long-acting male hormonal contraceptive.

Androgenic progestins in oral contraceptives and the risk of epithelial ovarian cancer

OBJECTIVE

Oral contraceptives (OCs) have been consistently linked to reduced risk of ovarian cancer. Oral contraceptive formulations display varying degrees of androgenicity. Data linking androgens to ovarian cancer suggest that OC androgenicity may impact efficacy in preventing ovarian cancer. The authors investigated whether OC efficacy might differ according to androgenicity by using data from a large, population-based, case-control study (the Steroid Hormones and Reproductions [SHARE] Study).

METHODS

Detailed data on OC formulation was obtained by an in-person interview for 568 cases and 1,026 controls. Multivariable logistic regression was used to assess the association of OC androgenicity with ovarian cancer while controlling for the known potential confounders of age, parity, family history of ovarian cancer, and tubal ligation.

RESULTS

Androgenic and nonandrogenic OCs conferred a similar and significant reduction in ovarian cancer risk (odds ratio 0.52, 95% confidence interval 0.35-0.76 and odds ratio 0.59, 95% confidence interval 0.45-0.78, respectively). No differences in duration of use, age at first use, and time since last use were found between androgenic and nonandrogenic formulations.

CONCLUSION

In general, the androgenicity of an OC does not alter chemopreventive efficacy.

LEVEL OF EVIDENCE

II-2.

Adolescents' experience with the combined estrogen and progestin transdermal contraceptive method Ortho Evra

BACKGROUND

The new combined estrogen & progestin contraceptive patch Ortho Evra was approved by the FDA in December 2001. To date, there is a paucity of data regarding its use in the adolescent age group. We examined adolescents' experience with this new contraceptive method.

METHODS

Using a questionnaire designed by the authors, care providers in a hospital based adolescent clinic interviewed and reviewed the charts of adolescent girls who had initiated Ortho Evra in 2002-2003.

RESULTS

Twenty-eight adolescent girls (age 18 +/- 1 years, gyn age 6 +/- 1 years, onset of sexual intercourse at 14 +/- 1 years, body mass index (BMI) 27.6 +/- 1.2, 57% Hispanic, 21% Caucasian, 11% African American, 7% biracial, 4% Indian American) who had used Ortho Evra for 7 +/- 1 months were enrolled. Half (50%) were adolescent mothers, and 57% had a history of irregular menstrual periods. All (100%) girls reported regular menstrual periods while using Ortho Evra, with only 14% experiencing occasional breakthrough bleeding. Half reported a shorter duration and 36% reported a lighter flow of their periods. About a third (39%) reported a decrease and 11% reported an increase in dysmenorrhea symptoms. About a third (29%) of those with a history of recurrent headaches at initiation reported decrease in headaches, and about a third (33%) of those with acne at initiation reported decrease in facial acne while on Ortho Evra. There were no significant BMI changes during Ortho Evra use. Although condom use while on Ortho Evra was poor (only 15% reporting consistent condom use), there were no pregnancies reported. A majority (93%) reported that they remembered to apply the patches on time, and 40% stated that Ortho Evra was easier than previous contraceptive methods. Two thirds (68%) were very satisfied and 29% were somewhat satisfied with the method, and 93% stated that they would recommend the method to a friend/relative. The preferred application site was the buttock (40%) followed by the lower abdomen (32%). About a fifth (21%) experienced at least one episode of complete patch detachment and 32% reported partial peeling of the patch corners. About a third (32%) would prefer another patch color, and 25% would like a fourth week placebo patch. The most common side effects were mild temporary application site reactions (64%), some discomfort on patch removal (32%), nausea (18%), and breast tenderness (18%). Eleven girls (39%) discontinued Ortho Evra (three lost health insurance, three because of application site reactions, two found patch application schedule difficult to remember, two desired pregnancy, two because of nausea, one because of perceived weight gain).

CONCLUSIONS

Ortho Evra provides excellent cycle control in adolescents. Most adolescents are satisfied with this method. Intensive efforts should be made to increase condom use by adolescents on Ortho Evra.

The therapeutic role of estrogens in postmenopausal women

This article reviews the history and present use of estrogens for the treatment of menopausal symptoms. It includes management of several different cases, including a review of all estrogens and estrogen/progestin preparations available in the United States.

Comparative evaluation of androgen and progesterone receptor transcription selectivity indices of 19-nortestosterone-derived progestins

Synthetic 19-nortestosterone-derived progestins show affinity for the androgen receptor (AR) and retain varying degrees of androgenic activity. In this study, AR- and progesterone receptor (PR)-dependent transcriptional activation induced by norethisterone (NET), levonorgestrel (LNG) and gestodene (GSD), and their 5alpha-reduced derivatives, including limited trypsin digestion of AR in the presence of natural and synthetic progestins were investigated. The results confirmed the progestogenic activity of the three 19-nortestosterone derivatives, which decreases after reduction of the 4-ene-double bound. These compounds were able to activate AR-dependent reporter gene expression, LNG and GSD being the stronger activators. 5alpha-Reduction of LNG and GSD did not change their androgenic transcriptional activity; however, the activation of AR by 5alpha-NET was four-fold higher than NET. The highest selectivity transcriptional index, as a measure of progestogenicity versus androgenicity, was obtained for NET. The 5alpha-reduced derivatives had values significantly lower than those of their parent compounds. Non-reduced and 5alpha-reduced 19-nortestosterone progestins induced virtually identical proteolysis fragmentation patterns of the AR to those observed with DHT.

Enhancing oral contraceptive success: the potential of new formulations

Reductions in oral contraceptive (OC) estrogen dose and the development of new progestins have resulted in formulations that maintain acceptable cycle control while improving safety. However, the potential safety benefits of low-estrogen doses may be offset by less acceptable cycle control. These observations have led to the development of 2 triphasic OC formulations containing norgestimate and desogestrel in combination with 25 microg ethinyl estradiol (EE). Both of these 25-microg EE triphasic OCs balance fewer estrogen-related side effects with good cycle control comparable to OCs containing higher estrogen doses. However, questions remain about the risk of venous thromboembolism associated with OCs containing desogestrel. A new monophasic 30-microg EE OC contains drospirenone, a spironolactone analogue with which there is limited experience. Although initial data with this OC are intriguing, product labeling highlights safety issues related to its antimineralocorticoid effects and the potential for hyperkalemia. Further experience with this formulation will determine its role in contraceptive practice.

All progestins are not created equal

A variety of progestins are available for therapeutic use. It is convenient to classify them into those related in chemical structure to progesterone or testosterone. Progestins related to progesterone can be subdivided into pregnanes and 19-norpregnanes, whereas those related to testosterone can be subdivided into those with and without a 17-ethinyl group. 17-Ethinylated progestins consist of the families of norethindrone (estranes) and levonorgestrel (13-ethylgonanes). Progestins administered orally undergo extensive hepatic first pass metabolism primarily by reduction and conjugation, and in most instances, relatively high progestin doses are required for therapeutic use. There are limited reliable data on the pharmacokinetics of most progestins. Some progestins are prodrugs, requiring transformation prior to exhibiting progestational activity. Qualitative and quantitative tests utilizing either human or animal species have been used to establish progestin potency. However, profound differences in progestational activity are often observed between human and animal tissues. Also, there is a misconception about androgenicity of progestins due largely to extrapolation of data from rat studies to the human. Progestins differ widely in their chemical structures, structure-function relationships, metabolism, pharmacokinetics, and potencies; they are not created equal.

Demonstration of progesterone receptor-mediated gonadotrophin suppression in the human male

OBJECTIVE

Synthetic gestogens in combination with testosterone have potential as a male hormonal contraceptive, predominantly acting by augmenting suppression of gonadotrophin secretion. Little is known, however, of the effects of gestogens in the male. Gestogens have affinity for both androgen and progesterone receptors but the relative contribution of action at these two receptors in gonadotrophin suppression remains unclear. In this study the effects of progesterone, with no significant androgen-receptor affinity are compared to desogestrel, a synthetic gestogen with relatively low affinity for the androgen receptor, on gonadotrophin secretion in normal men.

DESIGN

Subjects received either 50 mg progesterone intramuscularly (i.m.) or 300 micro g desogestrel orally daily for 7 days. Frequent blood sampling over 12 h was undertaken before and after drug administration. GnRH [100 micro g intravenously (i.v.)] was administered 2 h before the end of the frequent sampling period.

SUBJECTS

Twenty healthy men were randomly allocated to the two treatment groups.

RESULTS

Both progesterone and desogestrel administration resulted in decreases in the concentration of both LH and FSH secretion, as well as testosterone. Analysis of the pulsatile nature of LH secretion indicated that both treatments reduced LH pulse amplitude, and that progesterone reduced LH pulse frequency. Progesterone, but not desogestrel, treatment also reduced the increase in LH secretion in response to GnRH.

CONCLUSIONS

The effects of progesterone were at least as marked as those of a maximally effective dose of desogestrel. As progesterone has negligible affinity for the androgen receptor, these results are compatible with the suppressive effects of synthetic 19-norgestogens on gonadotrophin secretion in the male being mediated via the progesterone receptor, with its androgenicity contributing minimally to gonadotrophin suppression.

Hormone replacement therapy: optimising the dose and route of administration

Several new products and regimens for estrogen replacement in the postmenopausal woman have recently been introduced, giving physicians and patients greater choice not only in dose but also in route of administration. Estrogen treatment in the postmenopausal woman has several proven benefits for those who have vasomotor symptoms or problems related to urogenital atrophy. However, the most controversial area is in the long-term preventive benefits of estrogen against the development of osteoporosis and cardiovascular disease, particularly in women older than 60 years. It is in these areas that decisions on the dose and optimal route of administration of estrogen replacement therapy (ERT) must be made. Although adding a progestogen to an ERT regimen is mandatory, particularly in a woman with an intact uterus, discussion now focuses on which progestogen least attenuates the beneficial effects of estrogen. Emerging trends suggest that lower doses of estrogen (i.e. ethinylestradiol 5 microg/day, estradiol 0.25 mg/day or conjugated estrogens [CEE] 0.3 mg/day) continuously combined with lower doses of medroxyprogesterone (MPA) are equally effective at relieving vasomotor symptoms as the most commonly prescribed regimen in the US (CEE 0.625mg/MPA 2.5mg daily), with fewer adverse events, leading to greater patient acceptance and likelihood for continuation of therapy. This is especially important when therapy is initiated at an older age.

The effects of levonorgestrel on various sperm functions

Two doses of 750-microg levonorgestrel at 12 h apart is one of the regimens for emergency contraception. The mechanism of action of this regimen is not fully known. We investigated whether levonorgestrel influences sperm functions and thereby, exerts contraceptive activity. The motility, acrosome reaction, zona binding capacity, and oocyte fusion capacity of human spermatozoa treated with 1, 10, and 100 ng/mL levonorgestrel for 3 h were evaluated. Levonorgestrel decreased the curvilinear velocity of the treated spermatozoa in a dose-dependent manner. A significant decrease in straight-line velocity, average path velocity and linearity were also found with 100 ng/mL levonorgestrel treatment. This concentration of levonorgestrel, but not others, also marginally decreased (p = 0.045) the zona binding capacity of the treated spermatozoa. The steroid had no effect on acrosome reaction but had a dose-dependent inhibition on spermatozoa-oocyte fusion. These data show that levonorgestrel affects sperm function only at high concentration and the contribution of these effects to emergency contraception is unlikely to be significant.

Hormone-like behavioral effects of levonorgestrel and its metabolites in the male rat

Levonorgestrel (LNG), a contraceptive progestin, exhibits, besides its progestational activity, other hormone-like effects at the peripheral level. To assess whether LNG and its metabolites exert androgenic and/or estrogenic actions at the central nervous system (CNS), their effects on male sexual behavior in castrated rats were examined. LNG, 5alpha-dihydro LNG (5alphaLNG), and the 3alpha,5alpha- and 3beta,5alpha-tetrahydro derivatives of LNG (3alphaLNG and 3betaLNG, respectively) were administered for 3 weeks either alone (1000 microg/day) or in combination (300 microg/day) with 5alpha-dihydrotestosterone (DHT, 300 microg/day) or with estradiol-17beta (E(2), 5 microg/day). Copulatory behavior was assessed twice per week and sex accessory organs weights recorded at the end of treatments. LNG restored full copulatory behavior comparable to that of testosterone treated animals, although with a slight delay, whereas 5alphaLNG induced male sexual behavior in a significantly lower number of subjects. 3betaLNG and 3alphaLNG induced mounting but failed to restore intromission and ejaculation. Combined LNG+E(2) treatment fully activated mounting and intromission, but ejaculation was only partially restored. Combined 5alphaLNG+E(2) treatment and the combinations of 3alphaLNG or 3betaLNG with E(2) were significantly less effective, activating fewer intromissions and ejaculations. 3alphaLNG and 5alphaLNG, in combination with DHT, restored male sexual behavior. LNG, but not its metabolites, induced a significant increase on the weight of sex accessory organs. The overall results demonstrated that high doses of LNG induce a potent androgen agonistic behavioral effect and that its A-ring reduction diminishes this potency and enables a shift towards a weak estrogen-like effect.

Supplementation with vitamin C and/or vitamin B(6) in the prevention of Depo-Provera side effects in adolescents

BACKGROUND/OBJECTIVES

Depo-Provera-induced menstrual irregularity is believed to be secondary to relative estrogen deficiency. Weight gain associated with this contraceptive method is believed to be due to Depo-Provera's steroid-like appetite stimulation effect and to an altered tryptophan metabolism. We examined whether vitamin C, an important factor in uterine estrogen binding, and vitamin B(6), a glucocorticoid antagonist and an important coenzyme in the tryptophan-serotonin pathway, might alleviate menstrual irregularities and weight gain associated with Depo-Provera.

METHODS

Fifty-five adolescent girls (age 16 +/- 1 yr, gyn age 4 +/- 1 yr, body mass index 25.2 +/- 0.9) who decided to initiate Depo-Provera (150 mg intramuscularly every 3 months) were randomly assigned to one of four groups (group 1: vitamin B(6) 50 mg plus placebo pill/day; group 2: vitamin C 500 mg plus placebo pill/day; group 3: vitamin B(6) 50 mg plus vitamin C 500 mg/day; group 4 (control): 2 placebo pills/day) for 6 months. Participants were assessed by their care providers every 3 months.

SETTING

Two urban hospital-based adolescent clinics.

RESULTS

Number of days of bleeding during the first interval (first 3 months) as well as during the second interval (months 4-6) among groups 1, 2, and 3 did not differ statistically from days of bleeding in control group. There were no significant body mass index (BMI) changes among groups 1-3 (-0.15 +/- 0.18, 0.34 +/- 0.56, 0.01 +/- 0.31) compared with control (-0.38 +/- 0.38) during the first interval as well as during the second interval (0.68 +/- 0.37, -0.39 +/- 0.21, 0.45 +/- 0.32, compared with 0.28 +/- 0.43). When data from all 55 participants were collapsed, there was no significant change in BMI during the first 6 months of Depo-Provera use. About 48% at 3 months and 44% at 6 months were very or somewhat concerned about menstrual irregularity; 41% at 3 months and 18% at 6 months were very or somewhat concerned about weight changes. More than half (57%) at 3 months and 74% at 6 months reported less tampon/pad use, and 77% at 3 months and 78% at 6 months reported decreased menstrual cramps. Overall, 59% at 3 months and 70% at 6 months were very satisfied with Depo-Provera; 97% at 3 months and 96% at 6 months said that they would recommend Depo-Provera to a friend or a relative.

CONCLUSIONS

This study does not support a role for vitamin C in the prevention of Depo-Provera-induced menstrual irregularities or for vitamin B(6) in the prevention of weight changes associated with Depo-Provera. The unchanged BMI during the first 6 months of Depo-Provera use in the present study suggests that raising awareness and close follow-up may prevent weight gain among adolescent girls using this contraceptive method.

Estradiol and norgestimate: a review of their combined use as hormone replacement therapy in postmenopausal women

The focus of this review is hormone replacement therapy (HRT) with continuous administration of micronised, oral 17beta-estradiol 1 mg/day (herein referred to as continuous estradiol) plus micronised, oral norgestimate 90 microg/day administered for 3 days then withdrawn for 3 days in a 6-day repeating sequence (herein referred to as intermittent norgestimate). According to data from randomised, comparative trials of 1 year's duration, continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day relieves climacteric symptoms (vasomotor symptoms and vulvovaginal atrophy) in postmenopausal women. Continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day appeared as effective as estradiol 1 mg/day alone or continuous estradiol 2 mg/day plus continuous norethisterone acetate 1 mg/day in the treatment of postmenopausal women with vasomotor symptoms. Continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day was as effective as continuous estradiol 1 mg/day in causing the maturation of vaginal epithelial cells. In a randomised, double-blind study, bone mineral density (BMD) increased to a significantly greater extent and the rate of bone turnover was slower in postmenopausal women treated with continuous oral estradiol 1 mg/day plus intermittent norgestimate 90 microg/day than in placebo-treated patients. Two randomised, double-blind studies indicated that the addition of norgestimate 90 microg/day to continuous estradiol 1 mg/day did not attenuate the beneficial effects of estradiol on lipid parameters. Continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day was associated with increases in mean serum high density lipoprotein (HDL)-cholesterol levels and decreases in total cholesterol, low density lipoprotein (LDL)-cholesterol and lipoprotein (a) levels, compared with baseline. There was no statistically significant increase in triglyceride levels. In comparative trials, continuous oral estradiol 1 mg/day plus intermittent oral norgestimate 90 microg/day was well tolerated. Headache, breast pain or discomfort, abdominal pain or discomfort, uterine bleeding, dysmenorrhoea, oedema, nausea and depression were the most commonly reported adverse events. Continuous estradiol 1 mg/day plus intermittent oral norgestimate 90 microg/day was associated with a favourable uterine bleeding profile that improved over time. In a randomised trial, 80% of women were free from bleeding (irrespective of spotting) during month 12 of treatment. Norgestimate 90 microg/day was effective in protecting postmenopausal women against induction of endometrial hyperplasia by continuous estradiol 1 mg/day. In conclusion, data from a limited number of randomised studies indicate that HRT with continuous estradiol 1 mg/day plus intermittent norgestimate 90 microg/day is effective in relieving climacteric symptoms, increasing BMD and slowing the rate of bone turnover in postmenopausal women. This HRT regimen is well tolerated and is associated with a similar incidence of adverse events to that reported in recipients of continuous estradiol 1 mg/day. The norgestimate component of the regimen provides good endometrial protection and is associated with a favourable bleeding profile. Long-term studies investigating the associated risk of breast cancer and thromboembolic events in recipients of continuous estradiol plus intermittent norgestimate are needed. In the meantime, continuous oral estradiol plus intermittent oral norgestimate can be regarded as an effective new option for HRT in postmenopausal women.

A comparative and pooled analysis of the safety and tolerability of the contraceptive patch (Ortho Evra/Evra)

OBJECTIVE

To review the safety and tolerability of the contraceptive patch (Ortho Evra/Evra) versus a standard oral contraceptive (Triphasil) and to present the pooled safety and tolerability of the patch across three pivotal studies.

DESIGN

Three open-label, contraceptive studies of up to 13 treatment cycles.

SETTING

183 centers.

PATIENT(S)

Comparative study (812 patch, 605 oral contraceptive); pooled analysis (3,330 patch).

INTERVENTION(S)

The patch regimen was three consecutive 7-day patches (21 days) followed by 1 patch-free week per cycle; the oral contraceptive was dosed according to the U.S. physician package insert.

MAIN OUTCOME MEASURE(S)

Adverse events, laboratory tests, vital signs, and body weight.

RESULT(S)

The incidence of most events was similar between the patch and oral contraceptive groups, with the exception of a higher incidence of application site reactions, breast discomfort (cycles 1 and 2 only), and dysmenorrhea in the patch group. Pooled analysis demonstrated that most application site reactions (92%) and breast symptoms (86%) were mild or moderate in severity, and <2% of participants discontinued the patch because of either event. Only 7 (0.2%) participants experienced a serious adverse event classified as possibly, probably, or likely related to the patch. The mean change in body weight from baseline to the end of treatment was an increase of 0.3 kg.

CONCLUSION(S)

Overall, the contraceptive patch is well tolerated and has a side effect profile similar to an established oral contraceptive.

Assessment of the oestrogenic activity of the contraceptive progestin levonorgestrel and its non-phenolic metabolites

Levonorgestrel (13beta-ethyl-17alpha-ethynyl-17beta-hydroxy-4-gonen-3-one), a potent contraceptive progestin stimulates growth and proliferation of cultured breast cancer cells through a receptor-mediated mechanism, even though levonorgestrel does not bind to the oestrogen receptor (ER). To assess whether the oestrogen-like effects induced by this synthetic progestin are exerted via its metabolic conversion products, we studied the binding affinity of three A-ring levonorgestrel derivatives to the ER and their capability to transactivate an oestrogen-dependent yeast system co-transfected with the human ER gene and oestrogen responsive elements fused to a beta-galactosidase reporter vector. The results demonstrated that the 3beta,5alpha reduced levonorgestrel derivative and to a lesser extent its 3alpha isomer interact with the oestrogen receptor, with a significantly lower relative binding affinity (2.4% and 0.4%, respectively) than that of oestradiol (100%), while levonorgestrel does not. Both levonorgestrel metabolites were able to activate, in a dose-dependent manner, the beta-galactosidase reporter gene in the yeast expression system, an effect that was precluded by a steroidal antioestrogen. The oestrogenic potency of levonorgestrel metabolites was significantly lower (750-fold) than that of oestradiol. Furthermore, high doses of 3beta,5alpha levonorgestrel (2.5 mg/day/6 days) induced an increase of oestrogen-dependent progestin receptor in the anterior pituitary of castrated rats. The overall data offer a plausible explanation for the weak oestrogenic effects induced by high, non-pharmacological doses of levonorgestrel.

Preclinical profiles of progestins used in formulations of oral contraceptives and hormone replacement therapy

Progestins used in oral contraceptive formulations available in the United States include norgestimate, desogestrel, norethindrone, norethindrone acetate, and levonorgestrel. Progestins used in the United States in continuous and intermittent formulations of hormone replacement therapy are norgestimate, medroxyprogesterone acetate, and norethindrone acetate. The chemical structure of a progestin determines its relative binding affinity for the progesterone and androgen receptors, as well as the sex hormone binding globulin in human serum, and determines its clinical profile. Overall, the properties of levonorgestrel or norethindrone acetate in this regard differ from norgestimate and are more conducive to androgenic stimulation. Estrogen replacement offers cardioprotective effects in postmenopausal women. Progestins are added to hormone replacement therapy to counteract the well-known increased risk of endometrial hyperplasia associated with the use of unopposed estrogen. Animal models show that for some parameters, including improvement of lipid profiles, progestins can diminish the cardioprotective effect of estrogen. Initial animal studies of norgestimate combined with estrogen do not show an attenuation of estrogenic effects.

Comparison of a novel norgestimate/ethinyl estradiol oral contraceptive (Ortho Tri-Cyclen Lo) with the oral contraceptive Loestrin Fe 1/20

This multicenter study compared the contraceptive efficacy, cycle control, and safety of a new triphasic norgestimate (180/215/250 microg)/ethinyl estradiol 25 microg regimen (Ortho Tri-Cyclen Lo) (n = 1,723) with that of norethindrone acetate 1 mg/ethinyl estradiol 20 microg (Loestrin Fe 1/20) (n = 1,171). Healthy women were treated for up to 13 cycles. Demographics were similar between regimens. Contraceptive efficacy was comparable for Ortho Tri-Cyclen Lo and Loestrin Fe 1/20. The overall and method failure probabilities of pregnancy through 13 cycles were 1.9% and 1.5%, respectively, with Ortho Tri-Cyclen Lo and 2.6% and 2.4%, respectively, with Loestrin Fe 1/20. Breakthrough bleeding and spotting was reported by a significantly lower percentage of participants in the Ortho Tri-Cyclen Lo group compared with the Loestrin Fe 1/20 group. At representative Cycles 1, 3, 6, 9, and 13, breakthrough bleeding and spotting rates were 16.3, 11.5, 10.3, 7.9, and 7.7%, respectively, in the Ortho Tri-Cyclen Lo group and 34.9, 22.9, 22.2, 15.9, and 13.1%, respectively, in the Loestrin Fe 1/20 group. Compliance and safety data were similar for the two regimens.

Reporter cell lines are useful tools for monitoring biological activity of nuclear receptor ligands

To characterize the specificity of synthetic compounds for nuclear receptors, we established stable cell lines expressing the luciferase gene and different wild-type or chimaeric receptors. MCF-7 cells, which express the oestrogen receptor alpha (ER alpha), and HeLa cells, which do not express the oestrogen receptor, were transfected with a plasmid containing the luciferase gene downstream from a minimum promoter (beta-globin) and an oestrogen-responsive element, generating the MELN and the HELN cell lines, respectively. MELN cells enabled the detection of compounds that bind to the ER alpha or interfere with its pathway. HELN cells were used to establish stable transfectants expressing different nuclear receptors containing the DNA-binding domain of the oestrogen receptors. We thus established ER alpha or ER beta reporter cell lines by transfecting ER alpha or ER beta expression plasmids, and also retinoic acid receptor alpha, beta or gamma reporter cell lines by transfecting the chimaeric RAR gene, in which the DNA-binding domain was replaced by the ER alpha DNA-binding domain.

Minimal androgenic activity of a new oral contraceptive containing norethindrone acetate and graduated doses of ethinyl estradiol

The pharmacokinetics and androgenic activity of Estrostep, a new oral contraceptive providing low-dose estrogen in a graduated sequence with a constant dose of progestin, were characterized in an open-label, nonrandomized study in 17 normally cycling women treated for three cycles with Estrostep. Women received 1 mg of norethindrone acetate daily combined with 20 microg of ethinyl estradiol daily for the first 5 days (1/20), 30 microg of ethinyl estradiol daily for the next 7 days (1/30), and 35 microg of ethinyl estradiol daily for 9 days (1/35). No medication was given for 7 days in each cycle to allow for withdrawal bleeding. Serial blood samples for the measurement of ethinyl estradiol and norethindrone concentrations were collected on days 5, 12, and 21 of the third treatment cycle for the 1/20, 1/30, and 1/35 dose, respectively. Sex hormone-binding globulin (SHBG) and free testosterone were measured at baseline, on day 1 of cycles 2 and 3 (SHBG only), and on days 5, 12, and 21 of cycle 3. Mean steady-state plasma ethinyl estradiol and norethindrone concentrations increased over cycle 3. The increases in ethinyl estradiol concentrations were proportional to dose. The increases in norethindrone concentrations were related to ethinyl estradiol-dependent increases in SHBG concentrations, which were 218%, 253%, and 296% of baseline values on days 5, 12, and 21, respectively. Mean plasma free testosterone concentrations decreased 47%, 60%, and 64% below baseline on days 5, 12, and 21 of cycle 3, respectively. Graduated ethinyl estradiol doses combined with a constant norethindrone acetate dose progressively increase SHBG and decrease free testosterone, which overrides any theoretic concerns of androgenic activity of norethindrone acetate. Although true androgenic activity can be determined only by assessing endpoints such as acne, hirsutism, and lipids in large controlled trials, the observed changes in circulating SHBG and free testosterone concentrations indicate that Estrostep has little, if any, intrinsic androgenic activity.