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Background and Objectives: As the prevalence of some gynecological conditions depends on patient characteristics such as race/ethnicity, it is important to study therapies for these conditions in diverse populations. The study described in this article was conducted to investigate the safety, tolerability, and pharmacokinetics of vilaprisan, a selective progesterone receptor modulator, in Japanese women in Japan. It supplements two comparable studies that were conducted in healthy postmenopausal European and Chinese women, respectively., Methods: In this exploratory randomized, placebo-controlled, double-blind, ascending-dose study, five groups of healthy postmenopausal Japanese women received vilaprisan as immediate-release tablets (1, 5, or 15 mg as a single dose or 1 or 5 mg/day for 28 days) or placebo tablets (single dosing: 8 subjects/dose step, thereof 2 subjects randomized to placebo; multiple dosing: 12 subjects/dose step, thereof 4 subjects randomized to placebo). Blood samples for pharmacokinetic profiles were collected over 14-19 days. Safety assessments were based on adverse event data, vital signs, electrocardiograms, clinical laboratory tests, and transvaginal ultrasound examinations., Results: 48 participants were randomized, treated, and analyzed. Vilaprisan was rapidly absorbed, reaching maximum plasma concentrations (C max ) between 1 and 3 h post dose. Post maximum, plasma concentrations rapidly declined, indicating pronounced distribution into tissues. The exposure of vilaprisan increased roughly dose-proportionally: The geometric mean (geometric coefficients of variation) areas under the concentration time curves from time zero to infinity (AUC ∞ ) after single administration of 1, 5, or 15 mg vilaprisan were 67 µg·h/l (34%), 249 µg·h/l (15%), and 788 µg·h/l (37%), respectively. The AUC in the dosing interval after multiple administrations (AUC 24,md ) of 1 mg/day was 76 µg·h/l (59%), and the AUC 24,md after 5 mg/day was 311 µg·h/l (20%). Geometric mean C max values also increased roughly dose-proportionally: They amounted to 6 µg/l (22%), 16 µg/l (33%), and 52 µg/l (27%) after single administration and to 8 µg/l (28%) and 31 µg/l (22%) after multiple administrations of the above doses. Mild adverse events were observed, similar to those observed in other clinical studies of vilaprisan., Conclusions: Overall, vilaprisan was safe and well tolerated. The exposure in Japanese women was similar to that observed in European and Chinese women in separate studies., Trial Registration: 15 Nov 2011 (no registration number assigned)., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Altrenogest, a synthetic progestogen, is characterized by its estrus synchronization in mares, ewes, sows, and gilts. To investigate the pharmacokinetic profile and evaluate its accumulation in gilts, 18 oral doses of 20 mg altrenogest/gilt/day were given to eight healthy gilts at an interval of 24 hr. Plasma samples were collected, and altrenogest was determined by ultra-high-performance liquid chromatography with mass spectrometry. WinNonlin 6.4 software was used to calculate the pharmacokinetic parameters through noncompartmental model analysis. After the first administration (D 1), the pharmacokinetic parameters, including T max , C max , and the elimination half-life (T 1/2λz ), were similar to those observed after the final administration (D 18). However, the mean residence time at D 1 was significantly lower than D 18. As a whole, the mean steady-state plasma concentration (C ss ), degree fluctuation (DF), accumulation factor (R ac ), and area under the plasma concentration-time curve in steady state (AUC ss ) were 22.69 ± 6.15 ng/ml, 270.64 ± 42.51%, 1.53 ± 0.23, and 544.63 ± 147.49 ng hr/ml, respectively. These results showed that after 18 consecutive days of oral administration of altrenogest, plasma concentrations of altrenogest had a certain degree of fluctuation, without significant accumulations., (© 2019 John Wiley & Sons Ltd.)

The aim of this study was to explore the expression of PI3K, AKT, and P-AKT, and to investigate the role of PI3K/AKT signaling pathway in thin endometrium. We included 40 women treated in affiliated Shenzhen Nanshan People's Hospital of Guangdong Medical University for endometrial conditions between August 2013 and January 2015, 20 with a normal endometrium, and 20 with thin endometrium. The expression of PI3K, AKT, and P-AKT was evaluated by the immunohistochemical S-P method. The expression of PI3K, AKT, and P-AKT proteins was significantly lower in the thin endometrium group than in the normal endometrium group (P < 0.05). The expression of PI3K and AKT was positively correlated with the expression of P-AKT. The expression of PI3K, AKT, and P-AKT proteins in the thin endometrium decreases during the proliferative phase, and this process could be associated with PI3K/AKT signaling.

Co-administration of synthetic progestin containing hormonal contraceptives (HCs) and antiepileptic drugs (AEDs) is a common clinical situation which needs specific considerations due to drug interactions. Several studies have demonstrated that lamotrigine plasma levels are significantly decreased during co-medication with HCs, and that this interaction is associated with increased seizure frequency in most of the cases. Additionally, an increase in contraceptive failure and unintended pregnancy could be observed during co-medication. Hence, monitoring of progestin plasma levels in patients with AED co-medication is of interest. A rapid and reliable online solid-phase extraction-high performance liquid chromatography-tandem mass spectrometry (online SPE-LC-MS/MS) method using gradient elution in the LC domain was established and validated for the simultaneous quantitative determination of gestodene, dienogest, drospirenone, etonogestrel, cyproterone acetate, and levonorgestrel in human plasma. The online SPE-LC-MS/MS method covered a quantification concentration range of 5-100 ng/ml for dienogest, 1-100 ng/ml for etonogestrel and 2-100 ng/ml for all other analytes. Stable isotope-labeled internal standards were used for analyte quantification based on selected reaction monitoring experiments. Inter- and intra-assay precision and accuracy were determined from quality control (QC) samples at the lower limits of quantification and at low, medium, and high concentration levels within the calibration range. Inter-assay reproducibility at the QC levels was better than 10% (relative standard deviation, RSD), accuracy at these levels ranged from -3.7% to 11.3%. Total extraction efficiency, tested at three concentrations, ranged from 92.5% to 106.4%. Matrix interferences were excluded by post-column infusion experiments. To prove the applicability of the assay in clinical cohorts, a sample set (n = 298) stemming from study patients under AED/oral HC co-medication was screened for progestin plasma levels. This method has to be considered a research-use-only assay and must not be used for diagnostic or therapeutic purposes, since it did not undergo formal performance evaluation in the sense of the IVD directive (98/79/EG) of the European Community.

Background: Despite the effective role of adiponectin levels in the predisposition to type 2 diabetes mellitus, the potential impact of adiponectin in manifest type 2 diabetes is less studied., Objectives: This study aimed to determine gender-specific differences regarding the relationship between adiponectin levels and metabolic parameters as well as sex hormones in elderly type 2 diabetics., Methods: Sixty-two elderly type 2 diabetic men (mean age 60 [9] years) and 38 postmenopausal type 2 diabetic women (mean age 64 [9] years) were evaluated in a cross-sectional study. Glycemic control, lipids, sex hormones, adiponectin, and anthropometric parameters were measured in all participants., Results: Serum adiponectin was higher in women than in men (P < 0.006). After controlling for age and body mass index, adiponectin concentrations showed a positive correlation with sex hormone-binding globulin and high-density lipoprotein levels (P < 0.001) and a negative correlation with glycated hemoglobin, homeostasis model assessment index for insulin resistance, glucose, C-peptide, and triglyceride levels (P < 0.05) in all patients. In men, adiponectin significantly correlated with serum levels of testosterone (r = 0.420; P < 0.002). In women, negative correlations were observed between adiponectin levels and the fatty liver index (r = -0.492; P < 0.006) and γ-glutamyltransferase (r = -0.432; P < 0.01)., Conclusions: High serum adiponectin is a feature of better metabolic control and lipid profile, whereas low adiponectin levels are associated with fatty liver disease in women and low testosterone levels in men with type 2 diabetes., (Copyright © 2011 Elsevier HS Journals, Inc. All rights reserved.)

Treatment with the progestin altrenogest is widely used in pregnant mares. The fact that foals born from healthy mares treated with altrenogest until term suffered from neonatal problems raises the question of direct effects of altrenogest on vital functions in the neonate. We have therefore investigated altrenogest concentrations in maternal and neonatal blood plasma and in fetal fluids. Pregnant mares were treated with altrenogest orally once daily (0,088 mg/kg bodyweight, n = 7) or left untreated (n = 8) from 280 d of gestation until foaling. Altrenogest concentration was determined in plasma of the mares, their foals and in amniotic and allantoic fluid. The concentration of altrenogest in plasma from treated mares (2.6 +/- 1.0 ng/mL) was significantly lower than in plasma from their foals immediately after birth (5.6 +/- 1.9 ng/mL; p < 0.05), but was significantly higher than in their fetal fluids (amniotic fluid: 0.4 +/- 0.1 ng/mL; p < 0.05; allantoic fluid: 3.0 +/- 1.5 ng/mL). Altrenogest was undetectable in maternal and fetal plasma and fetal fluids of control pregnancies at all times. Altrenogest concentration in plasma of foals from treated mares was strongly correlated to the altrenogest concentration in plasma of their dams (r = 0.938, p < 0.001) and in amniotic (r = 0.886, p < 0.001) and allantoic fluid (r = 0.562, p < 0.05). A significant decrease in altrenogest concentration between the time periods 0-15 min, 30-120 min, and 180-360 min after parturition was seen in the plasma from foals born to altrenogest-treated mares. In conclusion, our data demonstrate that altrenogest reaches the equine fetus at high concentrations., (Copyright 2010 Elsevier Inc. All rights reserved.)

Progestogens were mostly used in hormone replacement therapy (HRT) in the postmenopause. Therefore, our knowledge about cardiovascular effects mainly originates from studies using HRT, whereby the progestogen effects were assessed according to clinical endpoints, metabolic effects and influence on vascular markers in vitro or in vivo, respectively. Furthermore, the progestogens can be characterised in terms of their partial receptor properties by specific experimental models. These properties can positively or negatively influence the vascular system. Concerning the direct vascular effects, currently research is focussing on biochemical vascular active markers. Although evidence strongly supports that some of these markers can be used as predictors of certain cardiovascular events, it remains to be established that modifying circulating levels of these markers will influence the outcomes. These experiments, however, strongly indicate that for the progestogens no class-effects can be postulated. In HRT progestogens are primarily used to get endometrial safety, which should be fulfilled by all progestogens. Since in terms of the vascular system it is difficult to predict the net-overall effect due to the different complex partial effects, we preferentially recommend progestogens derived from progesterone which are rather neutral in terms of the vascular system for risk patients but effective in the endometrium, i.e. maintaining atrophic endometrium during long-term continuous combined HRT. For women with hypertension especially HRT regimens can be recommended, which have been shown to stabilize or even lower blood pressure during well designed studies like with 24h-ambulatory blood pressure assessments. Further research is necessary to investigate the possibility of a more differential usage of the various progestogens regarding their effects on vascular systems.

Introduction: Sexual function in women in the reproductive age years is under psychological, sociocultural, and relationship influences, as well as the influence of sex hormones., Aim: To examine the data relating to sexual function in women in the reproductive age group, particularly the influence of sex hormones. To examine, in particular, the influence of the menstrual cycle, pregnancy, the oral contraceptive pill and endogenous and exogenous testosterone., Methods: Review of the literature on female sexual function, confining the search to the reproductive age range., Results: Population studies of sexual function identify sexual disinterest as being the most common sexual complaint in premenopausal women. Most studies of menstrual cyclicity identify a periovulatory increase in sexual desire or activity. All prospective studies of sexuality in pregnancy document a decline in sexual function with progression of pregnancy. Studies of the influence of the oral contraceptive pill on sexual function are contradictory with most prospective controlled studies showing no deleterious effect. Studies of the influence of endogenous androgens on sexuality are also contradictory with one large cross-sectional study showing no correlation, but some case-controlled studies show low androgens in women with sexual dysfunction. Studies of testosterone therapy in premenopausal women are ambiguous, with no clear dose-response effect., Conclusions: Sexual disinterest is prevalent in premenopausal woman despite being hormone replete. The assessment of androgen contribution is hampered by the unreliability of the testosterone assay in the female range. Large cross-sectional and longitudinal studies have not identified a correlation between testosterone and sexual function in women. Sexual dysfunction in the premenopausal age range is common. Sex hormones have a modifying effect on sexual function but social influences and learned responses are as important. The role of testosterone requires further study.

The Federation Equestre Internationale has permitted the use of altrenogest in mares for the control of oestrus. However, altrenogest is also suspicious to misuse in competition horses for its potential anabolic effects and suppression of typical male behaviour, and thus is a controlled drug. To investigate the pharmacokinetics of altrenogest in horses we conducted an elimination study. Five oral doses of 44 mug/kg altrenogest were administered to 10 horses at a dose interval of 24 h. Following administration blood and urine samples were collected at appropriate intervals. Altrenogest concentrations were measured by liquid chromatography-tandem mass spectrometry. The plasma levels of altrenogest reached maximal concentrations of 23-75 ng/mL. Baseline values were achieved within 3 days after the final administration. Urine peak concentrations of total altrenogest ranged from 823 to 3895 ng/mL. Twelve days after the final administration concentrations were below the limit of detection (ca 2 ng/mL).

Objective: To compare uterine tissue concentrations of ethinyl estradiol (EE) and etonogestrel (ENG) after one cycle of use of a contraceptive vaginal ring (NuvaRing; NV Organon, Oss, The Netherlands) or a combined oral contraceptive (COC)., Design: Randomized, open-label, pharmacokinetic study., Setting: Obstetrics and gynecology unit., Patient(s): Eight premenopausal women about to undergo hysterectomy but otherwise healthy., Intervention(s): One cycle (17-21 days) of NuvaRing or COC treatment that ended with surgical hysterectomy., Main Outcome Measure(s): Tissue concentrations of EE and ENG in uterine tissue samples taken from the upper myometrium and mid-myometrium, the cervical region, and the endometrium., Result(s): In both groups, concentrations of EE and ENG were similar in uterine tissue taken from the upper myometrium and mid-myometrium and the cervical region. However, compared with the COC group, concentrations of both hormones were markedly lower in tissue samples from the endometrium of women who had been treated with NuvaRing., Conclusion(s): Vaginal administration of hormones with NuvaRing did not produce elevated uterine concentrations of EE and ENG, compared with an oral contraceptive.

Objective: To investigate the effect of the levonorgestrel-releasing intrauterine system (LNG-IUS) in the treatment of idiopathic menorrhagia., Design: Measurements of menstrual blood loss (MBL), hemoglobin, and serum ferritin before and after LNG-IUS insertion., Setting: National Research Institute for Family Planning and Beijing Gynecology and Obstetrics Hospital, Beijing, People's Republic of China., Patient(s): Thirty-four patients with MBL over 80 mL., Intervention(s): Insertion of the LNG-IUS on cycle days 5-7 and follow-up at 3-month intervals for 3 years., Main Outcome Measure(s): Measurement of MBL, serum ferritin, and hemoglobin for evaluation of efficacy of treatment., Result(s): A significant reduction of MBL to 23.4 mL (78.7% decrease), 26.4 mL (83.8% decrease), 2.7 mL (97.7% decrease), and 13.7 mL (85.0% decrease) at 6, 12, 24, and 36 months, respectively. After 6 months, one-third of the patients experienced amenorrhea, and one-fourth, spotting. Hemoglobin increased significantly from 121.5 g/L preinsertion to 135.5 g/L after 36 months, while serum ferritin levels increased significantly from 21.9 ng/mL before insertion to 92.8 ng/mL after 36 months. In women using the LNG-IUS for 3-4 years, the E2 levels in 20 samples were 239.4 pmol/L, P levels were 11.1 nmol/L, and serum LNG levels were maintained at an average of 511 pmol/L., Conclusion(s): The significant reduction of MBL and the increase in hemoglobin and serum ferritin levels in the treatment of menorrhagia with the LNG-IUS has great implications for women's reproductive health, particularly in developing countries.

We describe the development of a serum chlormadinone acetate (CMA) time-resolved fluoroimmunoassay (TR-FIA). We prepared haptens (3-CMO-chlormadinone acetate and 6-chloropregna-4,6-dien-17,20-diol-3-one-20-hemisuccinate), biotinylated tracers (3(biotinylaminopropylamido) 3-CMO-chlormadinone acetate and 3-(6-chloropregna-4,6-dien-17,20-diol-3-one-20-hemisuccinylamino)1-biotinylaminopropane), and immunogens necessary for eliciting two antibodies (anti-chlormadinone acetate 3-CMO/BSA and anti-chlormadinone 20-hemisuccinate/BSA). The specificity of the assay was rigorously studied to eliminate possible interference by polar metabolites of CMA, particularly 17 alpha-acetoxy-6-chloro-3beta-hydroxypregna-4,6-diene-20-one (3beta-hydroxy metabolite), employing an easy-to-use ethylene glycol chromatographic step prior to immunoassay, so as to separate the polar metabolites, in particular the 3beta-hydroxy-CMA metabolite, from the intact CMA. The choice of the anti-CMA antibody was guided by the high assay sensitivity obtained with the anti-CMA 3-CMO/BSA antibody. The detection limit was 51pg/ml. Interassay reproducibility CVs were between 2.6 and 4.5%. This TR-FIA thus appeared to be a sensitive, specific, precise, and consequently well-suited method for measurement of serum CMA during a pharmacokinetic study in women.

A number of studies suggest that progestagens may have beneficial effects on bone metabolism. C(21) Progestin medroxyprogesterone acetate (MPA) is one of the most commonly prescribed progestins for hormone replacement therapy and in gynecologic practice. However, it appears that MPA with significant glucocorticoid (GC) activity may decrease bone density. In this review, we argue that bone loss associated with MPA administration is caused by decreased osteoblast differentiation as a result of MPA occupying the GC receptor, since increasing GC receptor occupancy beyond that reached at normal (= optimal) GC concentrations attenuates osteoblast differentiation. We propose that progestins with no GC activity may be a better choice for progestagen therapy to achieve more beneficial effects on bone metabolism.

We investigated the use of an orally active progestin (melengestrol acetate; MGA) to suppress reproductive activity in yearling beef bulls. Twenty-four crossbred bull calves were given a daily dose of 0, 0.5, 1.0, or 2.0 mg MGA for 99 d. Pulsatile patterns of LH and concentrations of testosterone and MGA were characterized on d 8, 36, 63, and 92 of the experiment. Numbers of aborted mounts, mounts with intromission, total mounts, and flehmen responses were assessed on d 15, 43, 71, and 99. Plasma concentrations of MGA were proportional to dose of MGA. Melengestrol acetate did not consistently affect mounting behavior in a dose-related manner, but, on d 99, number of total mounts for MGA-treated bulls was lower (P = 0.07) than that for control bulls. On d 15, MGA suppressed (P = 0.07) numbers of flehmen responses in a dose-dependent manner, but this effect was not sustained throughout the experiment. On d 8, concentrations of testosterone in control bulls were higher (P = 0.02) than in MGA-treated bulls, but this effect was not observed at other time periods. Overall, MGA caused slight decreases in mean concentrations of LH (P = 0.09) and LH pulse frequency (P = 0.06). Scrotal circumference was not affected by MGA. None of the behavioral traits was correlated with mean concentrations of LH or LH pulse frequency. Mounting activity was not correlated with testosterone concentrations, but number of flehmen responses was positively correlated with testosterone concentrations (P = 0.01). These results fail to support the hypothesis that progestins impair male sexual behavior or fertility in males.

Synthetic progestagens like melengestrol acetate (MGA) are widely used for oestrus synchronization and for growth promotion in cattle production. The metabolic effects exceed its primary potency as a progestagen. It is speculated that MGA stimulates follicle development and thereby endogenous oestrogen production, but inhibits ovulation. To investigate the dose-dependent effects on mRNA expression levels, six heifers were fed for 8 weeks with different levels of MGA (0.5, 1.5, 5 mg) daily and two heifers served as controls. The expression of steroid receptor mRNA [androgen receptor (AR), progesterone receptor (PR), oestrogen receptor (ER) ERalpha and ERbeta], insulin-like growth factor-1 (IGF-1) and its receptor were quantified in liver, neck (m. splenius) and shoulder muscularity (m. deltoideus). Plasma concentrations of IGF-1 were quantified by radioimmunoassay. In treated animals the MGA plasma levels were elevated over the complete treatment period, corresponding to the MGA treatment concentrations. IGF-1 concentrations of control animals were at constant levels. Plasma levels for oestradiol (E2) and IGF-1 were increased in the low MGA treatment group. Overdosed MGA decreased progesterone (P4) and E2 levels. To quantify the IGF-1 and all receptor mRNA transcripts, sensitive and reliable real-time reverse transcription-polymerase chain reaction (RT-PCR) quantification methods were developed and validated in the LightCycler. A dose-dependent relationship between increasing MGA concentration and mRNA expression was observed in liver for AR and IGF-1 receptor, and in neck muscularity for IGF-1. ERalpha in liver and neck muscle showed a trend of increasing expression.

Four different contraceptive implants for women, in the form of capsules or covered rods, that release either one of the synthetic progestins levonorgestrel, etonogestrel, Nestorone, or Elcometrine and nomegestrol acetate were considered. These progestins act by binding to their receptors located in diverse target cells, which are distributed along the hypothalamic-pituitary-gonadal-genital tract axis. These implants differ in the extent to which each one interferes with various steps of the reproductive process and in the intensity with which each one affects the same process along its effective life, but they have in common the ability to interfere with several key processes required for gamete encounter and fertilization. The steps they interfere with most are the ovulatory process, through partial or complete inhibition of the gonadotropin surge, and by changing the quality of cervical mucus; they restrict or suppress the access of fertile spermatozoa to the site of fertilization. Changes in endometrial development also occur, but this contribution to the contraceptive action is difficult to determine at the present time.

Four different implants, in the form of capsules or covered rods, that release one of the synthetic progestins levonorgestrel, etonogestrel, Nestorone, or Elcometrine and nomegestrol acetate were reviewed. Biocompatible polymers or copolymers of polydimethyl/polymethylvinyl-siloxanes or ethylvinylacetate are used to hold the steroid crystals and to control the rate of release. Once inserted under the skin, these implants release the corresponding steroid continuously over prolonged periods, a process that can be readily interrupted by implant removal. During long-term use of the implant, the released steroid circulates in blood at a fairly stable level. The physical characteristics of the implants, including drug contents and rate of release, serum levels of the progestin during use, and the duration of their effective life are described. Total steroid loads vary in the range of 50 mg to 216 mg; average release rates are in the range of 30-100 ug/day, and effective lives from 6 months to 7 years.

Objective: To report a case of Cushing syndrome associated with megestrol acetate therapy in a patient with renal insufficiency., Summary: A 17-year-old boy with renal insufficiency due to unilateral renal agenesis developed Cushing syndrome and worsening of his renal function after megestrol acetate therapy. The diagnosis was based on clinical and analytical evaluation., Discussion: Megestrol acetate is indicated for the treatment of cachexia associated with AIDS and malignancy. Due to its glucocorticoid activity, megestrol use has resulted in the occurrence of Cushing syndrome in both patient groups. We report the case of a young patient with renal insufficiency due to unilateral renal agenesis who developed Cushing syndrome two months after administration of high-dose (900-mg/d) megestrol acetate for an eating disorder., Conclusions: The risk of megestrol-induced Cushing syndrome, especially with high doses of the medication, should be considered as a possible adverse effect in patents with renal insufficiency.

Drospirenone is a novel synthetic progestogen with a pharmacological profile similar to that of natural progesterone. It has been developed in combination with ethinylestradiol for use as an oral contraceptive (EE/DRSP, Yasmin, Schering AG, Berlin, Germany). The pharmacokinetic characteristics of drospirenone and ethinylestradiol have been assessed in healthy female volunteers over a 1-year period. During each of the 13 treatment cycles, volunteers received the combined active ingredients for 21 days, followed by a 7-day, tablet-free interval. The concentrations of the serum proteins, sex hormone binding globulin (SHBG) and corticoid binding globulin (CBG), were determined at intervals after the cessation of treatment (day 21) at the end of cycles 1, 6, 9 and 13. Drospirenone and ethinylestradiol were found to be absorbed rapidly and to reach a peak concentration in serum 1.5-2.0 h after dosing. Serum concentrations ofdrospirenone declined, with mean terminal half-lives of 30.8-32.5 h. Accumulation of both drospirenone and ethinylestradiol was observed within a treatment cycle, with a mean accumulation ratio of 3.0 for drospirenone and 2.1 for ethinylestradiol. In addition, serum drospirenone concentrations increased between treatment cycles 1 and 6, but remained steady thereafter, as reflected in the AUC values determined at the end of treatment cycles 1, 6, 9 and 13. Serum SHBG and CBG concentrations declined in a biphasic manner after cessation of treatment at the end of cycle 13, and physiological steady-state concentrations were reached within 4-6 weeks. In conclusion, drospirenone was absorbed at a similar rate as other synthetic progestogens contained in various oral contraceptives, as indicated by similar tmax values. The terminal half-life of drospirenone was intermediate between those of 19-nortestosterone derivatives like desogestrel, levonorgestrel or gestodene and C21-progestogens like cyproterone acetate. Both active ingredients of the new contraceptive EE/DRSP showed accumulation within a treatment cycle, which is also the case with other synthetic progestogen/ethinylestradiol combinations. Similar to other oral contraceptives, a reversible induction of serum SHBG and CBG concentrations was observed under EE/DRSP treatment.

This paper reviews pharmacokinetic and pharmacodynamic studies with Implanon, which provides serum etonogestrel levels sufficient to inhibit ovulation within 8 h of insertion. After a peak of 813 pg/ml at 4 days, levels reach steady state (200 pg/ml) after 4-6 months and remain sufficient to prevent ovulation for 3 years. Variability is lower than with Norplant. Etonogestrel levels are similar in most ethnic groups, but 40% higher in women weighing < 50 kg. After implant removal, etonogestrel is not detectable within 1 week. Implanon inhibits ovulation by preventing the mid-cycle luteinizing hormone peak. Although it initially suppresses follicular development and estradiol production, ovarian activity slowly increases after 6 months, and follicle stimulating hormone and estradiol levels are almost normal. Endogenous progesterone levels remain in the subovulatory range for > 3 years in most subjects. In ovarian ultrasound studies, ovulation occurred in < 5% of users after 30 months of use. Ovulation was observed in most women within 3-4 weeks of implant removal. The pharmacokinetics and pharmacodynamics of Implanon indicate that it has high contraceptive efficacy, as reflected in a zero pregnancy rate over 5,629 woman-years of use. Its excellent reliability, ease of use, and reversibility make Implanon a valuable addition to current contraceptives.

Objective: Our purpose was to study combinations of estradiol and gestodene for prevention of bone loss in early postmenopausal women., Study Design: We randomly assigned 278 healthy, early postmenopausal women to receive either 2 mg 17beta-estradiol sequentially combined with 25 microg gestodene (group 2/25s), 2 mg estradiol sequentially combined with 50 microg gestodene (group 2/50s), 1 mg estradiol sequentially combined with 25 microg gestodene (group 1/25s), 1 mg estradiol continuously combined with 25 mg gestodene (group 1/25c), or placebo., Results: After 3 years the changes in bone mineral density of the spine were as follows (mean +/- SEM): group 2/25s, 7. 41% +/- 0.72%; group 2/50s, 8.53% +/- 0.90%; group 1.25s, 6.67% +/- 0.88%; group 1/25c, 4.44% +/- 0.59%; and placebo group, -2.03% +/- 0. 64%. The changes in bone mineral density were mirrored in the biochemical bone markers. The average responses for the urinary C-terminal telopeptide fragments of type I collagen corrected for creatinine excretion were as follows (mean of baseline +/- SEM): group 2/25s, -68.8% +/- 0.03%; group 2/50s, -72.8% +/- 0.02%; group 1/25s, -60.7% +/- 0.03%; group 1/25c, -52.28% +/- 0.04%; and placebo group, 6.5% +/- 0.09%. Beneficial lipid effects were found in all active groups. The decreases in low-density lipoprotein were as follows (mean +/- SEM): group 2/25s, -13.7% +/- 3.0%; group 2/50s, -14.6% +/- 3.2%; group 1/25s, -9.28% +/- 2.2%; group 1/25c, -9.92% +/- 2.4%; and placebo group, 1.53% +/- 1.9%., Conclusion: These results demonstrate that estradiol therapy with 1 mg estradiol is fully protective against early postmenopausal bone loss.

Unlabelled: About 30% of women population in Poland is already in the perimenopausal age. HRT (hormonal replacement therapy) is the best way of diminishing the unfavorable symptoms of this state., Aim of Study: The effect of HRT on ROI production by neutrophils before and after HRT, to determinate it's antioxidative influence on cells., Material: We have examined 40 women both from the Dept. of Menopausal Disease in the Research Institute Polish Mother's Memorial Hospital (RIPMMH) and Out Patient Menopausal Clinic of RIPMMH with average age of 49.8; between October 1997 and January 1998., Methods: We determined ROI generation by luminol-enhanced chemiluminescence, using standard stimuli like fLMP, PMA and OZ. We used Luminometer 1251, manufactured by Pharmacia-LKB. For statistic evaluation Fisher test, Kolmogorow-Smirnow test and T-student test were used., Results: We found that estrogen-progestagen therapy had a suppressive effect on generation of ROI by neutrophils in vitro and in vivo after using receptor dependent and non-dependent stimuli. ROI generation by neutrophils of peripheral blood induced by PMA, a receptor dependent stimuli, is diminished, both, after HRT or as an effect of estrogen-progestagen action in vitro. The results suggest direct inhibition effect on the neutrophil ability to ROI generation.

This paper describes experiments designed to test the effect of depot medroxyprogesterone acetate (DMPA) on calcium metabolism of adult ovariectomized rats. The 24 animals were randomly assigned to control or treated groups. Treated rats received 15 mg of DMPA i.m. per week, during four or twelve weeks. Controls received solvent alone. The variables characterizing the metabolism of Ca (daily rates of intestinal absorption and excretion, bone accretion and resorption and the sizes of the exchangeable pools and their rate constants) were measured with the aid of 45Ca according to Aubert and Milhaud. No effects were observed at four weeks of treatment. After twelve weeks, treatment produced serum levels of 46.5 +/- 5.6 nmoles of medroxyprogesterone/L, reduction of bone turnover (Ca accretion and resorption rates) and of the size of the slow exchanging Ca compartment. The increase in true Ca intestinal absorption was compensated by the increased endogenous fecal Ca excretion. The mass of body Ca was not affected by treatment.

Medroxyprogesterone acetate (MPA) is widely used in endocrine therapy for breast cancer and other diseases. Recently, it has been demonstrated that 9alpha-fluoromedroxyprogesterone acetate (FMPA) also has anti-tumour activity in chemical-induced rat mammary tumour and its activity is greater than that of MPA. In the present study, the physico-chemical properties of FMPA and MPA and their pharmacokinetics in female rats were investigated. Partition coefficients (log P) of FMPA and MPA were 3.1 and 3.8, respectively, while the solubilities of FMPA and MPA in phosphate buffer saline were 3.8 and 1.1 microg/mL, respectively. When the two agents were intravenously or orally administered into female rats, there was no significant difference between their plasma concentrations. However, unmetabolized drug excreted into urine accounted for 4.7 and 0.7% of the intravenous dose of FMPA and MPA, respectively. The free fraction of FMPA in rat plasma was approximately four times that of MPA. Assuming the well-stirred model, hepatic intrinsic clearances of FMPA and MPA were estimated to be 64 and 293 L/h per kg, respectively. In addition, the free fraction of FMPA in blood is estimated to be higher than that of MPA, which may explain the higher anti-tumour activity.

Objective: To evaluate the long-term effects of the new reformulated 2-rod Norplant implant on haemostasis in a prospective group of subjects who have completed 5 years of use., Methods: Data from 11 women who have completed 5 years' use of the new reformulated 2-rod subdermal implant from the original 16 women who were recruited and randomized to receive this new improved implant in a comparative study were analysed. Clinical assessment and serial blood sampling were done prior to insertion of implant and after 1, 3, 12, 18, 24, 36, 48 and 60 months of implant use. Each subject served as its own control and Analysis of Variance with Student-Newman-Kuels test was used for statistical analysis. The following parameters were determined: plasminogen activators (t-PA, u-PA), plasminogen activator inhibitor-1 (PAI-1), D-dimer, beta-thromboglobulin (beta-TG), thrombin-antithrombin (TAT)-complex, fibrinogen, Factor VII, platelets, haematocrit and haemoglobin levels., Results: No significant change was observed for t-PA levels in prolonged implant use. u-PA antigen showed a significant decrease whilst D-dimer were significantly elevated at only 24 months of implant use compared to pre-implant level. PAI-1 levels were not significantly changed but fibrinogen and FVII levels increased at 36 months and 42 months of use with enhanced platelet activation shown by beta-TG levels at 24 months. Platelet numbers were not affected by prolonged implant use. Haemoglobin concentration and haematocrit level showed significant fluctuations and then return to pre-implant level by 54 and 60 months., Conclusion: Enhanced fibrinolysis with platelet activation at 24 months of implant use were seen during the 60 months of 2-rod reformulated Norplant implant use. Hypercoagulable state was not observed although fibrinogen and FVII levels remain above the pre-implant levels as coagulation activation was not enhanced. The increased haemoglobin and haematocrit levels seen indicate enhanced bone marrow activity. There was no association between the use of reformulated 2-rod Norplant implant over 60 months of use and prothrombotic state.

Objective: To determine whether serum estradiol and dydrogesterone concentrations are associated with the occurrence of breakthrough bleeding., Methods: In a prospective, double-blind study, 194 postmenopausal women were allocated randomly to receive one of four doses of dydrogesterone (2.5 mg, 5 mg, 10 mg, 15 mg) continuously combined with 2 mg of micronized 17beta-estradiol. All medication was taken orally for a total of 168 days. Vaginal bleeding was recorded on a daily basis. Serum estradiol (E2) and dihydrodydrogesterone (the main metabolite of dydrogesterone) trough levels were measured at day 85 and at the end of the study (day 168). Bleeding pattern analysis was done according to the reference period method., Results: One hundred fifty-two of 177 women who completed the study supplied valid data on drug compliance, smoking habits, bleeding episodes, and serum hormone concentrations, which were used to assess the impact of serum E2 and dihydrodydrogesterone concentrations on the occurrence of breakthrough bleeding. Logistic regression analysis identified only the serum E2 concentration as having an independent, statistically significant effect (P = .003) on the occurrence of breakthrough bleeding; no such effect was associated with dihydrodydrogesterone levels (P = .118). The relative risk for the occurrence of breakthrough bleeding was 2.7 (95% confidence interval [CI] 1.454, 5.609) for serum E2 concentrations greater than 40 pg/mL., Conclusion: The occurrence of breakthrough bleeding during continuous combined hormone replacement therapy with estradiol and dydrogesterone in postmenopausal women was related to serum estradiol levels and not to dydrogesterone levels. Further studies are needed to test the hypothesis that estrogen is a major factor in the incidence of bleeding during postmenopausal hormone replacement therapy.

Objective: The aim of the study was to assess the dose-response effects on the postmenopausal endometrium of 3 sequential combined hormone replacement regimens and 1 continuous combined hormone replacement regimen of estradiol and gestodene., Study Design: In this 2-year double-blind, placebo-controlled study, 278 healthy postmenopausal women received either 2 mg estradiol sequentially combined with 50 microg or 25 microg gestodene, 1 mg estradiol sequentially or continuously combined with 25 microg gestodene, or placebo., Results: All 4 hormone treatment regimens produced a safe endometrial histologic appearance. The regimens that were based on the lower dose of 1 mg estradiol was associated with less uterine bleeding than were those that were based on 2 mg estradiol. For sequentially opposing the 2 mg dose of estradiol, the dose of 25 microg gestodene was less efficient in producing secretory activity than was the dose of 50 microg gestodene. The measurement of placental protein 14 in serum reflected the secretory transformation of the endometrial buildup., Conclusion: The reduction in bleeding episodes associated with regimens with lower estradiol doses may lead to improved long-term therapy compliance by menopausal women. The potency of progestogens can be assessed by measuring the serum concentration of placental protein 14.

Objective: To evaluate the effect of thalidomide on the plasma pharmacokinetics of ethinyl estradiol (INN, ethinylestradiol) and norethindrone (INN, norethisterone)., Methods: Ten women who had undergone surgical sterilization were enrolled in an open-label crossover study conducted in the Georgetown University Clinical Research Center. The pharmacokinetics of single doses of 0.07 mg ethinyl estradiol and 2 mg norethindrone were measured at baseline and after 3 weeks of 200 mg thalidomide. Compliance with the thalidomide regimen was assessed with use of Medication Event Monitoring System (MEMS) caps., Results: No changes were observed in the pharmacokinetics of ethinyl estradiol or norethindrone with thalidomide therapy. The mean +/- SD area under the plasma concentration-time curve (AUC0-infinity) for ethinyl estradiol was 6580 +/- 1100 ng.h/L at baseline and 5970 +/- 1560 ng.h/L after the thalidomide regimen (paired t test, P > .05). The values for norethindrone were 103 +/- 54 micrograms.h/L and 107 +/- 58 micrograms.h/L (paired t test, P > .05). No changes were observed for other pharmacokinetic parameters assessed for either ethinyl estradiol or norethindrone. No accumulation of thalidomide was seen after 21 days of therapy: day 1 AUC0-infinity 41.1 +/- 13.9 micrograms.h/mL; day 21 AUC0-infinity 59.6 +/- 27.3 micrograms.h/mL (paired t test, P > .05). No changes were observed for other pharmacokinetic parameters assessed for thalidomide between days 1 and 21. Thalidomide was well tolerated but caused variable degrees of sedation. The average thalidomide compliance rate was 97%., Conclusions: The pharmacokinetics of thalidomide do not change with 3 weeks of daily dosing. Thalidomide does not alter the pharmacokinetics of ethinyl estradiol or norethindrone. Therefore there is no drug interaction between thalidomide and these 2 drugs. The efficacy of oral contraceptives containing ethinyl estradiol and norethindrone should not be affected by concomitant thalidomide therapy.

The aims of this paper were to present data on the pharmacokinetics, clearance, bioavailability, and in vivo absorption of etonogestrel (ENG); to present the results of a longitudinal analysis of the plasma concentration-time curves of ENG; and to present the results of a cross-sectional analysis on the association of body weight with serum ENG concentrations. Implanon had an absorption rate of almost 60 micrograms/day after 3 months, which slowly decreased to 30 micrograms/day at the end of 2 years. The bioavailability over this period of time was constant and close to 100%. The clearance remained around 7.5 L/h. With a bioavailability and clearance that remained constant, it was concluded that accumulation of ENG does not occur. After Implanon insertion, serum concentrations increased within 8 h to concentrations associated with ovulation inhibition. Maximum mean serum concentrations (Cmax) amounted to 813 pg/mL and the time (tmax) to reach Cmax was 4 days. After reaching Cmax, ENG serum concentrations declined to about 196 pg/mL at the end of the first year, followed by a slow decline to 156 pg/mL at the end of the third year. After removal of Implanon, serum ENG concentrations declined to levels less than the detection limit of the assay (20 pg/mL) within 1 week. Lower body weight was associated with higher serum ENG concentrations.

Background: Circulating vasopressin and oxytocin are influenced by ovarian steroid blood levels, but the effect of estrogen and progestogen treatment on induced release of the posterior pituitary hormones is not clear., Methods: Eight postmenopausal women who had not been on hormonal replacement therapy for at least two months were included in the study. The women were treated for four weeks with transdermal administration of estradiol-17beta in a daily dose of 100 microg with the addition of 5 mg tablets of medoxyprogesterone twice daily for the last two weeks. A 25 minute intravenous infusion of hypertonic saline (0.06 mg/kg/min) was given before hormonal treatment, and after two and four weeks with serial plasma sampling for assay of vasopressin and oxytocin., Results: The mean basal concentration of vasopressin, which was 0.83+/-0.13 (SE) pmol/L before hormonal treatment, increased to a statistically significant degree after estradiol alone to 1.18+/-0.11 pmol/L and decreased after combined estrogen/progestogen treatment to 0.31+/-0.02 pmol/L. Sodium concentration and osmolality increased in a similar way during all three infusions, but the resultant increase in vasopressin concentration was significantly smaller and slower after treatment with estradiol alone than in the first experiment without pretreatment. The areas under the concentration curve for the second and third infusion were significantly smaller than when no hormone treatment was given. The induced hyperosmolality also caused a rise in oxytocin levels, but no influence of ovarian hormone treatment was observed., Conclusions: Ovarian hormone administration influences vasopressin secretion, affecting both the basal levels in plasma and the responses to an increase in plasma osmolality. The influence of ovarian hormones on oxytocin secretion is minimal.

The objective of this study was to determine whether progestin-only contraceptives induce thinning of the vaginal epithelium in nonhuman primates. Eight intact rhesus monkeys (four per group) were treated with either a single intramuscular injection of 30 mg of Depo-Provera or a subcutaneous insertion of Norplant-II (2 x 75 mg rods; day 0). Norplant-II rods were removed 90 days after insertion. Vaginal biopsies were obtained during a pretreatment menstrual cycle and following treatment on days 10, 30, 60, 118, and 146. Formalin-fixed vaginal biopsies were evaluated for epithelial thickness and the degree of keratinization. The circulating levels of estradiol, progesterone, medroxyprogesterone acetate (MPA), or levonorgestrel (LNG) were monitored throughout the study by specific radioimmunoassays. Circulating levels of estradiol and progesterone confirmed the stage of the menstrual cycle in which pretreatment biopsies were obtained. Following treatment with Depo-Provera, serum levels of MPA increased to 2.3 +/- 0.6 ng/ml (x +/- SE, n = 4) within 24 hr. Serum levels of MPA were maximal on day 14 (5.5 +/- 0.9 ng/ml), dropped below 1 ng/ml by day 50, and were nondetectable by day 70. Circulating levels of LNG were elevated 24 hr after insertion of Norplant-II (5.8 +/- 3.0 ng/ml), peaked on day 2 (7.6 +/- 4.2 ng/ml), remained between 1.4 and 6.2 ng/ml from days 14 to 90, and were nondetectable by day 118, the first serum sample after removal of Norplant-II. There were no significant differences (p > 0.05) in the epithelial thickness (microm), number of epithelial cell layers, or type of epithelium present in vaginal biopsies obtained during the follicular or luteal phases of the pretreatment menstrual cycle. Conversely, a pronounced effect of progestin treatment was observed on the vaginal epithelium. There were no significant differences (p > 0.05) between the two progestin treatment groups, but a significant effect (p < 0.05) over time was observed (two-way ANOVA). Compared with pretreatment menstrual cycle controls, the vaginal epithelial thickness was decreased (p < 0.05) by day 30 or 60 following Norplant-II insertion or Depo-Provera injection, respectively. The number of epithelial cell layers was also decreased (p < 0.05) on days 30 and/or 60 in progestin-treated monkeys compared with pretreatment control cycles. Following removal of Norplant-II or metabolic excretion of MPA, the vaginal epithellium regenerated and the thickness was no longer different (p > 0.05) from the pretreatment control cycle. These data demonstrate that progestin-only contraceptives induced thinning of the vaginal epithelium in rhesus monkeys, and this effect was rapidly reversible following physical or metabolic removal of the progestin.

Previous studies with postmenopausal women receiving oral doses of norethisterone-containing preparations have shown that a small fraction of the dose is converted metabolically to ethinyl estradiol and may be detected in the peripheral blood. To investigate the extent and the dose dependence of this conversion in more detail, we performed a study with 24 postmenopausal women who received single oral doses of 5 mg norethisterone as well as 5 and 10 mg norethisterone acetate with a washout phase of 2 weeks between each treatment. After each treatment, blood was collected at regular intervals and the concentrations of norethisterone and ethinyl estradiol were analyzed in the serum samples by a specific radioimmunoassay and by gas chromatography/mass spectrometry, respectively. Ethinyl estradiol was present in the serum samples of all women following treatment with norethisterone acetate and, except for four cases, also after treatment with norethisterone. The conversion ratio of norethisterone acetate to ethinyl estradiol was 0.7 +/- 0.2% and 1.0 +/- 0.4% at doses of 5 and 10 mg, respectively. This corresponded to an oral dose equivalent of about 6 micrograms ethinyl estradiol per milligram of norethisterone acetate. For norethisterone, a conversion ratio of 0.4 +/- 0.4% was found at a dose of 5 mg, which corresponded to an oral dose equivalent of about 4 micrograms ethinyl estradiol per milligram of norethisterone. Although it cannot be excluded that in individual cases, even higher doses of ethinyl estradiol may be produced by conversion, it is concluded that at therapeutic doses of the progestogens, the exposure to metabolically derived ethinyl estradiol is probably of little clinical significance not only in fertile women using oral contraceptive combination preparations containing norethisterone and ethinyl estradiol, but also in postmenopausal women who receive oral doses of estradiol for estrogen replacement. The estrogenic effects of metabolically derived ethinyl estradiol on the liver (eg. synthesis of transport proteins) are very likely more than compensated due to the androgenic activity of norethisterone.

In a randomized, single dose, open crossover study in 24 healthy women, aged between 20 and 28 years, the relative bioavailability of the test product Mini 30 (0.03 mg levonorgestrel) in comparison to a reference, Microval, was investigated after single dose administration. Because there was a difference in the in vitro dissolution test, it was of interest whether this difference had an influence on the extent and rate of absorption. Whereas 99.4% of the test were dissolved after 20 minutes, only 48.3% of the reference were dissolved after 45 minutes, 74.8% after 120 minutes and 95.5% after 240 minutes. Blood samples were taken from time 0-72 hours after administration. All serum samples were analyzed twice in a radioimmunoassay which was validated before the start of the study. The limit of quantitation was at 50 pg/ml. The AUC0 -infinity ratio test/reference and the 90% confidence interval were 104.8%, and 99.10%, respectively. The Cmax ratio test/reference and the 90% confidence interval were 175.5%, and 159.8%-192.8%, respectively. With regard to the extent of absorption (AUC0-infinity) the 2 preparations were within the acceptance range for bioequivalence whereas they were outside the acceptance range for the rate of absorption (Cmax). The elimination half-lives of LNG did not differ between the test and reference preparations (25.08 +/- 11.94 h, and 25.70 +/- 10.08 h, respectively). So, the in vitro results concerning the rate of dissolution were confirmed by the in vivo findings in Cmax whereas regarding the extent of absorption (AUC) there were no differences between the 2 preparations.

Safety, contraceptive efficacy and biodegradability of subdermal norethindrone (NET)-cholesterol implants (Anuelle) were investigated in 19 healthy, sexually active women. Mean serum NET levels in women with four and five pellets, containing 174 mg and 266.5 mg NET, showed a "burst-effect" of 3.17 and 3.71 ng/ml, respectively, within 24 h post implantation. Subsequently, for the four- and five-pellet groups, respectively, the levels declined from 0.75 to 0.40 ng/ml and 1.05 to 0.61 ng/ml during the months 12-15, from 0.40 to 0.11 ng/ml and 0.61 to 0.25 ng/ml up to month 36. The serum NET levels were undetectable at 36 months and beyond, indicating complete biodegradability of NET pellets. Serum E2 levels remained within normal limits (> 50 pg/ml), whereas serum P indicated anovulatory cycles in 78% of the four-pellet group and 99% of the five-pellet group. FSH and LH levels were subnormal and acyclic. Plasma lipids showed reduced total and LDL cholesterol and triglycerides. HDL cholesterol remained unchanged. Drug-related adverse effects were essentially limited to irregular bleeding. There were no pregnancies in either group.

Background: The serum interleukin (IL)-6 concentration was very low in patients with metastatic breast carcinoma who had received oral medroxyprogesterone acetate (MPA) treatment as compared with those who had not. Accordingly, the authors conducted a prospective study to determine whether MPA treatment reduces the serum level of IL-6 in patients with this disease., Methods: In 21 consecutive Japanese patients who were scheduled to receive oral MPA treatment at doses of 600, 800 or 1200 mg/day, serum concentrations of IL-6 were determined with a sensitive enzyme-immunoassay prior to the administration of MPA and again at 4 weeks after the treatment was started. In addition, plasma levels of MPA were determined by high-performance liquid chromatography (HPLC)., Results: Four weeks after the oral MPA therapy was started, serum IL-6 levels decreased in all 21 patients regardless of whether or not they responded to the treatment. Although the extent of decrease in the serum IL-6 (delta IL-6) did not correlate with the daily dose of MPA, it correlated closely with the plasma MPA level in these patients. Subjective improvement in appetite and weight gain were more frequent in the delta IL-6 > 3 pg/mL group compared with the delta IL-6 < or = 3 pg/mL group (80% vs. 45% and 70% vs. 45%, respectively). Similar results were obtained for improvement in patients' sense of well-being (100% vs. 55%)., Conclusions: Oral MPA treatment reduces serum IL-6 concentration in patients with metastatic breast carcinoma, but the decrease is not associated with response to MPA. This observation may indicate a potential of this agent for producing subjective improvement.

Chlormadinone acetate (GS implant, CMA) pellet, a synthetic luteal hormone preparation, was subcutaneously implanted at 5, 10 and 20 mg/kg in four normal male dogs ranging in age from 3 to 10 years to determine the changes in the prostatic volume, peripheral plasma levels of sex hormones and semen quality. The plasma levels of CMA, LH, testosterone (T) and 5 alpha-dihydrotestosterone (DHT) were measured by radioimmunoassay. The prostatic volume was measured by computed tomography. The semen was collected by digital manipulation. The pellet was removed 26 weeks after implantation. The effects of CMA pellet implantation were examined during implantation and until 22 weeks after removal. The prostatic volume was reduced to 61 +/- 3 (mean +/- S.E., n = 4), 52 +/- 5 (n = 4) and 53 +/- 9 (n = 4)% of the preimplantation volumes in the 5, 10 and 20 mg/kg groups, respectively. The plasma CMA levels in the 10 mg/kg and 20 mg/kg groups peaked at 2 weeks, but were gradually decreased. At 22 weeks after removal of the pellet, the prostatic volume returned to 74-85% of the preimplantation volumes. The plasma LH levels tended to increase after implantation in all groups. The plasma T and DHT levels were slightly decreased in all groups. In the 10 and 20 mg/kg groups, the number of sperm and motility sperm was reduced, and the rate of abnormal sperm increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Currently available chromatographic assays of the progestative drug nomegestrol acetate in human plasma are not suitable for monitoring drug kinetics more than 24 h after clinical dosage. A specific and sensitive enzyme immunoassay was therefore developed. A 3(O-carboxymethyl)oxime derivative of nomegestrol acetate was synthesized and coupled to bovine serum albumin in order to raise polyclonal antibodies in rabbits. The enzymatic tracer was obtained by coupling the 3(O-carboxymethyl)oxime derivative to acetylcholinesterase (E.C.3.1.1.7.). HPLC fractionation of human plasma samples followed by enzyme immunoassay revealed the presence of cross-reacting metabolites. An automated procedure of metabolite separation was developed using silica bonded with diol groups (Diol Bakerbond column). This procedure ensured assay specificity. The quantification limit in human plasma was 0.1 ng/ml. Mean repeatability (intra-assay variation) and reproducibility (inter-assay variation) were 9 and 15%, respectively. The enzyme immunoassay allowed monitoring of the kinetics of nomegestrol acetate 144 h after oral administration of a single 5 mg dose. Values for human samples were in excellent agreement with those assayable by HPLC followed by u.v. detection.

The pharmacokinetics of gestodene (GEST) and ethinylestradiol (EE2) were determined in 14 healthy women (age 18 to 32 years) during a treatment period of three months with a new tri-step combination oral contraceptive (Milvane). Prior to this treatment period, the same women received a single administration of a coated tablet containing 0.1 mg GEST together with 0.03 mg EE2. There was a wash-out phase of one week between both treatments. Following single dose administration, a mean terminal half-life of 18 h was observed for GEST. The total clearance was 0.9 ml x min-1 x kg-1 and the volume of distribution was 84 l. During a treatment cycle, GEST levels in the serum accumulated by a factor of 8 as compared to single dose administration. Steady-state drug levels were reached during the second half of each cycle. As compared to single dose administration, the following changes were observed for GEST at the end of treatment cycles one and three: prolonged terminal half-life (20 to 22 h), reduced total (0.16 ml x min-1 x kg-1) and free clearance (ca. 27 ml x min-1 x kg-1), reduced volume of distribution (ca. 18 l). A concomitant EE2-induced increase in the SHBG concentrations by a factor of three as compared to pretreatment values was observed during a treatment cycle and appeared to be mainly responsible for the changes in the pharmacokinetics of GEST. Marked changes were also seen for the serum protein binding of GEST. After single dose administration, the free fraction of GEST was 1.3% and the fractions bound to SHBG and albumin were 69.4% and 29.3%, respectively. At the end of cycle one, the free fraction was only 0.6% and the fractions bound to SHBG and albumin were 81.4% and 18.0%, respectively. There was no difference in corresponding pharmacokinetic parameters and in the serum protein binding of GEST at the end of cycles one and three. On the last day of treatment cycles one and three, the AUC(0-4h) values of EE2 were 299.2 and 278.1 pg x ml-1 x h, respectively, which corresponds to an about 30% increase as compared to single dose administration, where an AUC(0-4h) value of 216.1 pg x ml-1 x h was found. Total and free testosterone concentrations decreased during treatment cycles one and three by about 36% and 60%, respectively, compared with the corresponding values measured prior to treatment. The fraction of unbound testosterone thus decreased from 0.5% to 0.3% during treatment.

Ethylene-vinyl acetate (EVA) polymeric contraceptive implants (Implanon) containing 3-keto-desogestrel have been prepared aiming at an in vitro initial release rate of 60 micrograms 3-keto-desogestrel/day. These implants are designed to have an intended life-time of 2 years. During a 3-year period, the release of these implants was studied in 4 dogs after subdermal insertion, using plasma clearance of 3-keto-desogestrel assessed after intravenous administration of 3-keto-desogestrel and steady state plasma levels of 3-keto-desogestrel. The mean plasma level of 3-keto-desogestrel decreased gradually during the first year of the study, viz. from 1.64 nmol/1 at 7 days after implantation to 0.69 nmol/l after one year. At the end of the second year, the level had decreased further to 0.45 nmol/l while after 3 years, the mean 3-keto-desogestrel plasma level was 0.42 nmol/l. The calculated mean daily release of 3-keto-desogestrel decreased during the first year from 70 micrograms/day to 30 micrograms/day. During the second and third year, the decrease in release rate was much less, viz. going from 30 micrograms/day to 28 micrograms/day and from 28 micrograms/day to 25 micrograms/day, respectively. This indicates a much more constant release during the second and third year of the study. The calculated cumulative amount of 3-keto-desogestrel released from the implant during the dog study was 34.0 mg. Based on the initial amount of 3-keto-desogestrel in the implant of 68.3 mg, the remaining amount in the implants at termination of the study should be approximately 34.3 mg. Actually, the mean remaining amount of 3-keto-desogestrel was 33.8 mg, which is in very close agreement with the calculated value. Implants from the same batch as used in the in vivo study were also analyzed for the in vitro release at regular times during the 3-year study period. After one year, the in vitro release rate was about 43 micrograms/day whereas this release rate was 33 and 27 micrograms/day after 2 and 3 years, respectively. Although the in vitro set-up constantly gave a somewhat higher release in comparison with the in vivo release, it is apparent that the in vitro procedure is valuable for prediction of the in vivo release characteristics of the implant. There were no indications for 3-keto-desogestrel accumulation at the implantation site. No local irritations were seen and the animals had no discomfort at all.(ABSTRACT TRUNCATED AT 400 WORDS)

Results from two clinical pharmacokinetic studies are given. The first study was an observational study in oral contraceptive users who took either a combination of gestodene and ethinyl estradiol (pill A, Femovan) or desogestrel and ethinyl estradiol (pill B, Marvelon). A total of 69 women (39 receiving pill A and 30 receiving pill B) were evaluated to determine serum ethinyl estradiol, sex hormone-binding globulin, corticosteroid-binding globulin, and cortisol levels. Samples were obtained on 1 day during the tenth to twenty-first days of pill intake. All women received the respective oral contraceptive for at least 3 months. The test power was such that an 80% difference of 1 standard deviation of each target variable would have been detected (alpha = 0.05; beta = 0.1). No statistically significant differences were found in sex hormone-binding globulin, corticosteroid-binding globulin, or cortisol serum levels between both groups. Time and height of maximum ethinyl estradiol levels were identical as was the area under the curves. Ex vivo protein-binding analysis of the progestins revealed a free portion of 0.6% for gestodene and 2.5% for 3-ketodesogestrel as the active metabolite of desogestrel. Sex hormone-binding globulin-bound portions were much higher for gestodene (75.3% +/- 9.1%) than for 3-ketodesogestrel (31.6% +/- 12%). The remaining fractions were bound to albumin. In a second study, ethinyl estradiol-bioequivalence from pills A and B was investigated in 18 women in a controlled, single-dose, randomized, crossover design. The area under the ethinyl estradiol serum levels were identical up to 4 hours after pill intake between both treatments. According to the relatively low variation in data in this group of women, a 10% difference in ethinyl estradiol-availability could have been detected. Both studies indicate that the pharmacokinetics of ethinyl estradiol were independent of the concomitantly administered progestin, that is, desogestel and gestodene.

Oral contraceptives have not been associated with exacerbation of epilepsy despite warnings in package inserts. No clinical study has provided scientific evidence of worsening of seizures in epileptic women who use oral contraceptives, and improvement in seizure control has occurred in some cases. The main concern about use of oral contraceptives in this population is their effectiveness in preventing conception. Failure rates are higher in groups of women taking enzyme-inducing antiepileptic drugs. The degree of increased metabolism of estrogen and progestin components is highly variable and unpredictable among individuals. Use of higher doses increases protection against conception but also increases the risk of side effects, particularly in patients in whom no enzyme induction occurs. The strength of hormones in the pill should be selected individually when initiating use. Some women may require higher doses for full contraceptive effect.

In a cross-over study with orally administered desogestrel (0.150 mg) plus ethinyloestradiol (0.030 mg) and 3-keto-desogestrel (0.150 mg) plus ethinyloestradiol (0.030 mg) in ten women under steady-state conditions, the serum levels of 3-keto-desogestrel were monitored by radioimmunoassay. No statistically significant differences between treatment groups were found with respect to the areas under the curve of the serum levels versus time (AUC), peak heights and peak times. The individual AUCs for 3-keto-desogestrel after dosing with desogestrel (plus EE) or 3-keto-desogestrel (plus EE) show a similar degree of variation. The biotransformation of desogestrel into 3-keto-desogestrel is rapid and appears not to be limited by the metabolic capacity of the normal liver.

For the radioimmunological determination (RIA) of the progestagen dienogest (1, 17 alpha-Cyanomethyl-17 beta-hydroxy-estra-4,9-dien-3-one) in plasma three methods of sample preparation were tested and compared: Extraction of plasma samples with dichlormethane (I), binding of plasma dienogest to an antiserum added; removal of non-bound steroids by means of activated charcoal, extraction of dienogest using dichlormethane (II), using the RIA without extraction of plasma samples after partial precipitation of proteins by means of ammonium sulphate (III). The reliability of the dienogest-RIA is, characterized by a limit of detection of 3.2 pg (I, III) and 5 pg (II) per tube, respectively, by "within-assay"- and "between-assay" variation coefficients of 3 to 5% and 3 to 9%, respectively, in parallel determinations and by a high rate of recovery of dienogest (greater than 90%) added to plasma. The application of the parallelism test method to different plasma volumes confirms the accuracy of method I and II. When method III was applied to plasma samples with low concentrations of dienogest parallelism wasn't found in all cases.

A sensitive and specific method is described for the determination of norgestomet in bovine plasma as low as 10 ppt with better than 83% average recovery and a relative standard deviation (RSD) of range 1-3%. Norgestomet is separated from the bulk of the endogenous substances in plasma by adsorption on a PrepSep C18 extraction column and elution with acetonitrile. The residue after evaporation of acetonitrile is reacted with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride to form syn and anti geometric isomers of the mono-oxime derivative. The derivative, after further clean-up and evaporation of solvent, is reconstituted with cyclohexane, and an aliquot is analyzed by capillary column gas chromatography/negative chemical ionization mass spectrometry using methane as the carrier gas. Selected ion monitoring was employed to detect the [M - HF]- fragment ion of the norgestomet mono-oxime derivative (m/z 547) and its dideuterated mono-oxime analog (m/z 549) which serves as the internal standard. Quantification is achieved by using the Quantitative Selected Ion Monitoring Processing System (QSIMPS) software to generate a standard curve of fragment ion area ratios v. concentration of norgestomet, and then calculate sample concentrations.

Disposition and excretion of the progestin Dienogest (17 alpha-cyanomethyl-17 beta-hydroxy-estra-4,9-dien-3-one, STS 557) were investigated in female rabbits. Following single and repeated administration of the tritium-labelled compound the plasma concentration courses of total radioactivity (Dienogest + metabolites) and of the parent drug alone were estimated and also the urinary and fecal excretion of total radioactivity. From these data basic pharmacokinetic parameters were calculated. Additionally, the enterohepatic recirculation of biliary excreted metabolites was studied using bile of donors for oral administration to recipients. Following oral administration the high bioavailability of Dienogest which was already found in other animal species and in man could also be confirmed with rabbits. The parameters of Dienogest disposition do not differ significantly from those of the progestin levonorgestrel. Thus, the different effects of the both progestins in the McPhail-Clauberg assay in the rabbit cannot be attributed to differences in pharmacokinetics.

A novel method is described for the measurement of nanogram quantities of clogestone acetate (3beta, 17alpha-dihydroxy-6-chloropregna-4,6-dien-20-one 3,17-diacetate) in serum:clogestone acetate (CgAc) is converted to chlormadinone acetate in the presence of wheat germ lipase and hydroxysteroid dehydrogenase. The ketonic steroid formed is then incubated with rat uterine cytosol and 3-H-progesterone. The concentration of 3CgAc is estimated from a standard curve derived by incubating cytosol with 3-H-progesterone and varying amounts of chlormadinone acetate. The statistically validated method has been used for the estimation of serum CgAc in humans and dogs given an oral dose of the steroid. The radioreceptor assay (RRA), has practical advantages over related techniques such as radioimmunoassay (RIA) especially with respect to the developmental work. This is the first time that a quantitative assay of a progestin by the tissue receptor approach has been described.