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Devoy T, Smith N. Sugammadex and oral contraceptives. Curr Opin Anaesthesiol 2024; 37:338-343. [PMID: 38841921 DOI: 10.1097/aco.0000000000001397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
PURPOSE OF REVIEW This review article explores the evidence regarding sugammadex (MSD Australia) and its potential interaction with hormonal contraceptives. The impact of recent clinical trials and review articles is examined. RECENT FINDINGS Recent clinical data suggest that the interaction between sugammadex and estrogen and progesterone concentrations may not be clinically significant and may confer some protection against ovulation. There are no clinical trials reporting interactions between sugammadex and the exogenous hormonal compounds found in oral contraceptive pills. The method of contraception is an important consideration, as sugammadex theoretically affects oral and nonoral, and combined versus single agent methods differently. Two large retrospective database studies have reported two cases of pregnancy postoperatively in patients on hormonal contraceptives whose anesthetic included sugammadex. SUMMARY Strong clinical evidence to support or refute claims of a significant impact of sugammadex on contraceptive efficacy in women on contraception is lacking. The existing evidence does not suggest a basis for concern regarding the impact of sugammadex on contraception in the perioperative setting.
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Affiliation(s)
- Tamblyn Devoy
- Department of Anaesthetics, Wollongong Hospital, Wollongong
| | - Natalie Smith
- Department of Anaesthetics, Wollongong Hospital, Wollongong
- Department of Anaesthetics, St George Hospital, Kogarah
- School of Clinical Medicine, University of New South Wales, Kensington
- Graduate School Medicine, University of Wollongong, Wollongong, New South Wales, Australia
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2
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Kamal El-Deen A, Elmansi H, Shimizu K. Natural hydrophobic deep eutectic solvent for vortex-assisted dispersive liquid-liquid microextraction of anti-prostate cancer triple therapy from water and human plasma. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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3
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Aronson JK, Ferner RE. Analysis of reports of unintended pregnancies associated with the combined use of non-enzyme-inducing antibiotics and hormonal contraceptives. BMJ Evid Based Med 2021; 26:112-113. [PMID: 32817012 DOI: 10.1136/bmjebm-2020-111363] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/30/2020] [Indexed: 11/04/2022]
Abstract
BACKGROUND Enzyme-inducing antibacterial drugs can impair the efficacy of hormonal contraceptives. Suspicion that other antibiotics might do likewise led to advice that extra contraceptive precautions should be taken during a course of antibiotics. However, current advice is that the purported interaction does not occur, based on small studies observing few pregnancies, assuming that all women are susceptible, and without measuring unbound hormone concentrations. OBJECTIVE To test the null hypothesis that antibiotics do not impair the effectiveness of oral contraceptives. DESIGN A database review of Yellow Card reports to the UK's Medicines and Healthcare products Regulatory Agency. DATA Spontaneous reports of suspected adverse drug reactions in people taking antibacterial drugs (n=74 623), enzyme-inducing medicines (n=32 872), or control medicines (n=65 578). MAIN OUTCOME MEASURES Reports of the primary outcome-unintended pregnancies; reports of cardiac arrhythmias and headaches (control events); reports of congenital abnormalities (positive control events); and reports of diarrhoea (a possible confounding factor). RESULTS Compared with control medicines, unintended pregnancies were seven times more commonly reported with antibiotics and 13 times more commonly reported with enzyme inducers (the positive controls). Congenital abnormalities were reported seven times more often with enzyme inducers but were not more common with antibiotics. Diarrhoea was not a confounding factor. CONCLUSION This study provides a signal that antibacterial drugs may reduce the efficacy of hormonal contraceptives. Women taking hormonal contraceptives should be warned that antibiotics may impair their effectiveness. Extra precautions can be taken during a course of antibiotics; an unintended pregnancy is a life-changing event.
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Affiliation(s)
- Jeffrey K Aronson
- Centre for Evidence Based Medicine, Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford OX2 6GG, Oxfordshire, UK
| | - Robin E Ferner
- Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
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4
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Bick AJ, Louw-du Toit R, Skosana SB, Africander D, Hapgood JP. Pharmacokinetics, metabolism and serum concentrations of progestins used in contraception. Pharmacol Ther 2021; 222:107789. [PMID: 33316287 PMCID: PMC8122039 DOI: 10.1016/j.pharmthera.2020.107789] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 11/24/2020] [Indexed: 02/07/2023]
Abstract
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.
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Affiliation(s)
- Alexis J Bick
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch 7700, South Africa
| | - Renate Louw-du Toit
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7602, South Africa
| | - Salndave B Skosana
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch 7700, South Africa
| | - Donita Africander
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7602, South Africa
| | - Janet P Hapgood
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch 7700, South Africa; Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa.
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5
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Barra F, Vitale SG, Seca M, Scala C, Leone Roberti Maggiore U, Cianci A, Ferrero S. The potential role of elagolix for treating uterine bleeding associated to uterine myomas. Expert Opin Pharmacother 2020; 21:1419-1430. [PMID: 32401547 DOI: 10.1080/14656566.2020.1755254] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
INTRODUCTION Uterine myomas represents a widespread gynecological disease of women in reproductive age. Although surgery remains the first choice for treating most patients, in the last years, new medical approaches have been considered in order to ameliorate heavy menstrual bleeding (HMB) related to their presence. Elagolix is a second-generation gonadotropin-releasing hormone (GnRH) antagonist under investigation for the long-term treatment of uterine myomas. AREAS COVERED The aim of this drug evaluation is to give a complete overview of pharmacokinetic and pharmacodynamic data on elagolix for treating HMB related to uterine myomas and to report the results of the current clinical trials in this setting. EXPERT OPINION In two previous phase II studies, this drug succeeded in ameliorating blood loss and quality of life of patients affected by uterine myomas with a good safety profile. Three phase III trials (ELARIS UF-I, UF-II, and EXTEND) investigated the efficacy, tolerability, and safety of elagolix at 300 mg twice daily with add-back therapy. The primary endpoint, consisting in the reduction in HMB compared to placebo, was met in the majority of patients under treatment. Currently, elagolix is under investigation in two other ongoing multicenter phase III clinical studies.
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Affiliation(s)
- Fabio Barra
- Academic Unit of Obstetrics and Gynaecology, IRCCS Ospedale Policlinico San Martino , Genova, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (Dinogmi), University of Genova , Italy
| | - Salvatore Giovanni Vitale
- Obstetrics and Gynecology Unit, Department of General Surgery and Medical Surgical Specialties, University of Catania , Catania, Italy
| | - Marta Seca
- Academic Unit of Obstetrics and Gynaecology, IRCCS Ospedale Policlinico San Martino , Genova, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (Dinogmi), University of Genova , Italy
| | - Carolina Scala
- Unit of Obstetrics and Gynecology, Gaslini Institute , Genova, Italy
| | | | - Antonio Cianci
- Obstetrics and Gynecology Unit, Department of General Surgery and Medical Surgical Specialties, University of Catania , Catania, Italy
| | - Simone Ferrero
- Academic Unit of Obstetrics and Gynaecology, IRCCS Ospedale Policlinico San Martino , Genova, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (Dinogmi), University of Genova , Italy
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6
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Tietz K, Klein S. In Vitro Methods for Evaluating Drug Release of Vaginal Ring Formulations-A Critical Review. Pharmaceutics 2019; 11:pharmaceutics11100538. [PMID: 31623277 PMCID: PMC6836189 DOI: 10.3390/pharmaceutics11100538] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/09/2019] [Accepted: 10/14/2019] [Indexed: 12/28/2022] Open
Abstract
The vagina is a promising site for both local and systemic drug delivery and represents an interesting administration route for compounds with poor oral bioavailability. Whereas most of the currently marketed dosage forms were designed as immediate release formulations, intravaginal rings (IVRs) offer the possibility of a controlled vaginal drug delivery over several weeks or months. For a long time, the development of IVRs was limited to steroid-releasing formulations. Recently, IVRs have witnessed a surge of new interest as promising delivery systems for microbicides. Therefore, various novel IVR designs have been introduced. To ensure that only safe and effective IVRs will be administered to patients, it is important to properly distinguish between IVRs with desired and undesired release performance. In vitro methods for evaluating drug release of IVRs that present with sufficient predictive capacity for in vivo drug release, and discriminatory power with regard to IVRs quality, are an essential tool for this purpose. The objective of the present review article is to present the current status of in vitro drug release testing of IVRs and to critically discuss current compendial and non-official in vitro drug release methods with regard to their discriminatory power and in vivo predictivity.
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Affiliation(s)
- Katharina Tietz
- Center of Drug Absorption and Transport, Institute of Biopharmaceutics and Pharmaceutical Technology, Department of Pharmacy, Felix-Hausdorff-Str. 3, University of Greifswald, Greifswald 17489, Germany
| | - Sandra Klein
- Center of Drug Absorption and Transport, Institute of Biopharmaceutics and Pharmaceutical Technology, Department of Pharmacy, Felix-Hausdorff-Str. 3, University of Greifswald, Greifswald 17489, Germany.
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Tejería E, Giglio J, Fernández L, Rey A. Development and evaluation of a 99mTc(V)-nitrido complex derived from estradiol for breast cancer imaging. Appl Radiat Isot 2019; 154:108854. [PMID: 31442798 DOI: 10.1016/j.apradiso.2019.108854] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/02/2019] [Accepted: 08/11/2019] [Indexed: 01/10/2023]
Abstract
Estrogen receptors are overexpressed in 70% of breast cancer and identification of their presence is important to select the appropriate treatment. This work proposes the preparation and evaluation of an estradiol derived as potential ER imaging agent. Ethinylestradiol was derivatized to introduce a dithiocarbamate function for Tc coordination. Labeling was achieved through the formation of a symmetric Tc(V)-nitrido complex with a radiochemical purity (RCP) > 95%. Physicochemical evaluation, cell uptake, biodistribution in normal animals and in nude mice bearing induced ER + breast tumors showed promising results.
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Affiliation(s)
- Emilia Tejería
- Área de Radioquímica, Facultad de Química, General Flores 2124, Universidad de La República, 11800, Montevideo, Uruguay
| | - Javier Giglio
- Área de Radioquímica, Facultad de Química, General Flores 2124, Universidad de La República, 11800, Montevideo, Uruguay.
| | - Leticia Fernández
- Área de Radioquímica, Facultad de Química, General Flores 2124, Universidad de La República, 11800, Montevideo, Uruguay
| | - Ana Rey
- Área de Radioquímica, Facultad de Química, General Flores 2124, Universidad de La República, 11800, Montevideo, Uruguay.
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8
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Perkins MS, Louw-du Toit R, Africander D. Hormone Therapy and Breast Cancer: Emerging Steroid Receptor Mechanisms. J Mol Endocrinol 2018; 61:R133-R160. [PMID: 29899079 DOI: 10.1530/jme-18-0094] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/04/2018] [Accepted: 06/12/2018] [Indexed: 12/31/2022]
Abstract
Although hormone therapy is widely used by millions of women to relieve symptoms of menopause, it has been associated with several side-effects such as coronary heart disease, stroke and increased invasive breast cancer risk. These side-effects have caused many women to seek alternatives to conventional hormone therapy, including the controversial custom-compounded bioidentical hormone therapy suggested to not increase breast cancer risk. Historically estrogens and the estrogen receptor were considered the principal factors promoting breast cancer development and progression, however, a role for other members of the steroid receptor family in breast cancer pathogenesis is now evident, with emerging studies revealing an interplay between some steroid receptors. In this review, we discuss examples of hormone therapy used for the relief of menopausal symptoms, highlighting the distinction between conventional hormone therapy and custom-compounded bioidentical hormone therapy. Moreover, we highlight the fact that not all hormones have been evaluated for an association with increased breast cancer risk. We also summarize the current knowledge regarding the role of steroid receptors in mediating the carcinogenic effects of hormones used in menopausal hormone therapy, with special emphasis on the influence of the interplay or crosstalk between steroid receptors. Unraveling the intertwined nature of steroid hormone receptor signaling pathways in breast cancer biology is of utmost importance, considering that breast cancer is the most prevalent cancer among women worldwide. Moreover, understanding these mechanisms may reveal novel prevention or treatment options, and lead to the development of new hormone therapies that does not cause increased breast cancer risk.
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Affiliation(s)
- Meghan S Perkins
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Renate Louw-du Toit
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Donita Africander
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
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9
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Ezuruike U, Humphries H, Dickins M, Neuhoff S, Gardner I, Rowland Yeo K. Risk-Benefit Assessment of Ethinylestradiol Using a Physiologically Based Pharmacokinetic Modeling Approach. Clin Pharmacol Ther 2018; 104:1229-1239. [PMID: 29637542 PMCID: PMC6282492 DOI: 10.1002/cpt.1085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/09/2018] [Accepted: 03/14/2018] [Indexed: 02/03/2023]
Abstract
Current formulations of combined oral contraceptives (COC) containing ethinylestradiol (EE) have ≤35 μg due to increased risks of cardiovascular diseases (CVD) with higher doses of EE. Low‐dose formulations however, have resulted in increased incidences of breakthrough bleeding and contraceptive failure, particularly when coadministered with inducers of cytochrome P450 enzymes (CYP). The developed physiologically based pharmacokinetic model quantitatively predicted the effect of CYP3A4 inhibition and induction on the pharmacokinetics of EE. The predicted Cmax and AUC ratios when coadministered with voriconazole, fluconazole, rifampicin, and carbamazepine were within 1.25 of the observed data. Based on published clinical data, an AUCss value of 1,000 pg/ml.h was selected as the threshold for breakthrough bleeding. Prospective application of the model in simulations of different doses of EE (20 μg, 35 μg, and 50 μg) identified percentages of the population at risk of breakthrough bleeding alone and with varying degrees of CYP modulation.
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Affiliation(s)
| | | | | | | | - Iain Gardner
- Simcyp Limited (a Certara company), Sheffield, UK
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10
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Barra F, Scala C, Ferrero S. Current understanding on pharmacokinetics, clinical efficacy and safety of progestins for treating pain associated to endometriosis. Expert Opin Drug Metab Toxicol 2018; 14:399-415. [PMID: 29617576 DOI: 10.1080/17425255.2018.1461840] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
INTRODUCTION Endometriosis is a chronic estrogen and progestogen responsive inflammatory disease associated with pain symptoms and infertility. The medical therapy of endometriosis aims to induce decidualization within the hormonally dependent ectopic endometrium, and it is often administered to ameliorate women' pain symptoms or to prevent post-surgical disease recurrence. A variety of progestins have been used in monotherapy for the medical management of women with endometriosis. Areas covered: This review aims to offer the reader a complete overview of pharmacokinetic (PK) and clinical efficacy of progestins for the treatment of endometriosis. Expert opinion: Each progestin has a distinct PK parameters and pharmacodynamics affinity not only for progesterone receptor, but also for other steroid receptors, such as estrogen, androgen, and glucocorticoid. Moreover, progestins can also be delivered in different formulations. All these characteristics influence their final biological effect. Randomized, controlled, non-blinded studies support the use of oral progestin-only treatment for pelvic pain associated with endometriosis. Currently, the only two progestins approved by Food and Drug Administration (FDA) for the treatment of endometriosis are norethindrone acetate (NETA) and depot medroxyprogesterone acetate (DMPA).
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Affiliation(s)
- Fabio Barra
- a Academic Unit of Obstetrics and Gynecology , Ospedale Policlinico San Martino , Genoa , Italy.,b Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI) , University of Genoa , Genoa , Italy
| | - Carolina Scala
- a Academic Unit of Obstetrics and Gynecology , Ospedale Policlinico San Martino , Genoa , Italy.,b Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI) , University of Genoa , Genoa , Italy
| | - Simone Ferrero
- a Academic Unit of Obstetrics and Gynecology , Ospedale Policlinico San Martino , Genoa , Italy.,b Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI) , University of Genoa , Genoa , Italy
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11
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Comparing the androgenic and estrogenic properties of progestins used in contraception and hormone therapy. Biochem Biophys Res Commun 2017; 491:140-146. [PMID: 28711501 DOI: 10.1016/j.bbrc.2017.07.063] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 07/11/2017] [Indexed: 11/21/2022]
Abstract
Progestins used in endocrine therapies bind to multiple steroid receptors and are associated with several side-effects. It is thus important to understand the relationship between steroid receptor cross-reactivity and the side-effect profile of progestins. In cell lines that express negligible levels of steroid receptors, we report for the first time the binding affinities, potencies and efficacies of selected progestins from different generations determined in parallel. We show that the progestins bind to the androgen receptor (AR) with similar affinities to each other and progesterone, while none bind estrogen receptor (ER)-β, and only norethisterone acetate, levonorgestrel and gestodene bind ERα. Comparative dose-response analysis revealed that progestins from the first three generations display similar androgenic activity to the natural androgen dihydrotestosterone for transactivation, while norethisterone acetate, levonorgestrel and gestodene are ERα agonists. We show for the first time that the anti-androgenic properties of progesterone and drospirenone are similar to the well-known AR antagonist hydroxyflutamide, while nomegestrol acetate is more potent and nestorone less potent than both hydroxyflutamide and progesterone. Moreover, we are the first to report that the older progestins, unlike progesterone and the fourth generation progestins, are efficacious ERα agonists for transrepression, while the selected progestins from the second and third generation are efficacious AR agonists for transrepression. Considering the progestin potencies and their reported free serum concentrations relative to dihydrotestosterone and estradiol, our results suggest that the progestins are likely to exert AR-, but not ERα- or ERβ-mediated effects in vivo.
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12
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Churchwell MI, Camacho L, Vanlandingham MM, Twaddle NC, Sepehr E, Delclos KB, Fisher JW, Doerge DR. Comparison of life-stage-dependent internal dosimetry for bisphenol A, ethinyl estradiol, a reference estrogen, and endogenous estradiol to test an estrogenic mode of action in Sprague Dawley rats. Toxicol Sci 2014; 139:4-20. [PMID: 24496641 DOI: 10.1093/toxsci/kfu021] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Bisphenol A (BPA) was administered by gavage (2.5-300,000 μg/kg body weight (bw)/day) to pregnant Sprague Dawley dams, newborn pups, and continuing into adulthood. Aglycone (i.e., unconjugated and active) and conjugated (i.e., inactive) BPA were evaluated by liquid chromatography electrospray tandem mass spectrometry (LC-ES/MS/MS) in serum to better interpret toxicological endpoints measured in the study. Ethinyl estradiol (EE2, 0.5 and 5 μg/kg bw/day) and the endogenous hormones, 17β-estradiol (E2) and testosterone, were similarly evaluated. Mean BPA aglycone levels in vehicle and naïve control rat serum (0.02-0.5 ng/ml) indicated sample processing artifact, consistent with literature reports of a propensity for postexposure blood contamination by BPA. Direct measurements of BPA-glucuronide in vehicle and naïve control serum (2-10nM) indicated unintentional exposure and metabolism at levels similar to those produced by 2.5 μg/kg bw/day BPA (7-10nM), despite careful attention to potential BPA inputs (diet, drinking water, vehicle, cages, bedding, and dust) and rigorous dosing solution certification and delivery. The source of this exposure could not be identified, but interpretation of the toxicological effects, observed only at the highest BPA doses, was not compromised. Internal exposures to BPA and EE2 aglycones were highest in young rats. When maximal serum concentrations from the two highest BPA doses and both EE2 doses were compared with concurrent levels of endogenous E2, the ERα binding equivalents were similar to or above those of endogenous E2 in male and female rats of all ages tested. Such evaluations of estrogenic internal dosimetry and comprehensive evaluation of contamination impact should aid in extrapolating risks from human BPA exposures.
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Affiliation(s)
- Mona I Churchwell
- U.S. Food and Drug Administration, National Center for Toxicological Research, Division of Biochemical Toxicology, 3900 NCTR Road, Jefferson, Arkansas 72079
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Grandi G, Cagnacci A, Volpe A. Pharmacokinetic evaluation of desogestrel as a female contraceptive. Expert Opin Drug Metab Toxicol 2013; 10:1-10. [DOI: 10.1517/17425255.2013.844229] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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14
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Stanczyk FZ, Archer DF, Bhavnani BR. Ethinyl estradiol and 17β-estradiol in combined oral contraceptives: pharmacokinetics, pharmacodynamics and risk assessment. Contraception 2013; 87:706-27. [DOI: 10.1016/j.contraception.2012.12.011] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 12/25/2012] [Accepted: 12/25/2012] [Indexed: 11/16/2022]
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15
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Stanczyk FZ, Hapgood JP, Winer S, Mishell DR. Progestogens used in postmenopausal hormone therapy: differences in their pharmacological properties, intracellular actions, and clinical effects. Endocr Rev 2013; 34:171-208. [PMID: 23238854 PMCID: PMC3610676 DOI: 10.1210/er.2012-1008] [Citation(s) in RCA: 292] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
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.
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Affiliation(s)
- Frank Z Stanczyk
- Department of Obstetrics and Gynecology, University of Southern California Keck School of Medicine, Livingston Research Building, 1321 North Mission Road, Room 201, Los Angeles, California 90033, USA.
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Westhoff CL, Torgal AH, Mayeda ER, Petrie K, Thomas T, Dragoman M, Cremers S. Pharmacokinetics and ovarian suppression during use of a contraceptive vaginal ring in normal-weight and obese women. Am J Obstet Gynecol 2012; 207:39.e1-6. [PMID: 22727346 DOI: 10.1016/j.ajog.2012.04.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 04/12/2012] [Accepted: 04/23/2012] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Many observational studies indicate higher oral contraceptive failure among obese women, but most clinical trials and physiologic studies do not support these differences. Limited data indicate higher failure rates among obese contraceptive patch users. Data regarding contraceptive vaginal ring performance in obese women are needed. STUDY DESIGN Twenty normal weight (body mass index [BMI] 19.0-24.9; median, 21.65) and 20 obese (BMI 30.0-39.9; median, 33.7) women enrolled in a prospective study of ethinyl estradiol (EE(2)) and etonorgestrel pharmacokinetics and of ovarian follicle development, endometrial thickness, and bleeding patterns, all measured biweekly during the second cycle of contraceptive vaginal ring use. RESULTS Thirty-seven women completed follow-up. Mean day 0-21 EE(2) concentrations were lower among obese vs normal weight women (15.0 vs 22.0 pg/mL, respectively, P = .004), whereas etonorgestrel concentrations were similar (1138 vs 1256 pg/mL, respectively, P = .39). Follicular development was minimal in both groups, with only 5 women achieving a maximum follicle diameter >13 mm at any time during 3 weeks follow-up (3 normal weight and 2 obese women); these women had serum progesterone levels <1.0. Obese women reported more bleeding or spotting than normal weight women (3.6 vs 1.4 days, respectively, P = .01). CONCLUSION Although obese women had lower EE(2) levels during contraceptive vaginal ring use, they had excellent suppression of ovarian follicle development, similar to normal weight women. This predicts that contraceptive vaginal ring effectiveness will be similar in women with a BMI up to 39.9. The lower serum EE(2) levels in the obese women may explain the greater reported bleeding or spotting days.
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Affiliation(s)
- Carolyn L Westhoff
- Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
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Karjalainen MJ, Neuvonen PJ, Backman JT. In vitroInhibition of CYP1A2 by Model Inhibitors, Anti-Inflammatory Analgesics and Female Sex Steroids: Predictability ofin vivoInteractions. Basic Clin Pharmacol Toxicol 2008; 103:157-65. [DOI: 10.1111/j.1742-7843.2008.00252.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Benagiano G, Primiero FM. Seventy-Five Microgram Desogestrel Minipill, A New Perspective in Estrogen-Free Contraception. Ann N Y Acad Sci 2003; 997:163-73. [PMID: 14644823 DOI: 10.1196/annals.1290.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Progestin-only minipills have been available for over three decades, yet their use has been limited, because of a documented lower efficacy when compared to pills that combine estrogen and progestin. The availability of a new low-dose progestin-only minipill containing 75 microg desogestrel (DSG) offers a new perspective, since, in a large multicenter study, this minipill gave a crude Pearl index of 0.41 and an adjusted one of 0.14, which is comparable to indices found in clinical trials of oral contraceptives. This minipill also allows for a 12-hour tolerance time in taking the pill. The high effectiveness of the DSG minipill is attributable to an almost constant inhibition of ovulation, as shown by the absence of elevated progesterone circulating levels and inhibition of follicular growth in the vast majority of cycles studied. Since irregular bleeding patterns are observed with all minipills, patterns experienced with DSG 75 microg have been compared to those obtained with levonogestrel 30 microg. As expected, the more pronounced ovarian inhibition produced wider bleeding variability with DSG, but also less bleeding overall. The DSG minipill is suitable for lactating women and represents a valuable addition to oral contraception.
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Affiliation(s)
- Giuseppe Benagiano
- Department of Gynaecological Sciences, Perinatology, and Perinatal Care, University La Sapienza, 00161 Rome, Italy.
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19
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Gruschke A, Kuhl H. Validity of radioimmunological methods for determining free testosterone in serum. Fertil Steril 2001; 76:576-82. [PMID: 11532484 DOI: 10.1016/s0015-0282(01)01939-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To assess serum free testosterone (free T) concentrations in various groups of women by means of an ultrafiltration technique (UFT) or two RIAs and to investigate the influence of levonorgestrel (LNG) and norethisterone (NET) on free T. DESIGN Experimental study with serum samples from various groups of patients. SETTING Obstetrics and gynecology department of a university. PATIENT(S) Samples from 20 normal healthy women, 20 menopausal women, 21 pregnant women, 23 women using oral contraceptives (OC), 20 hyperandrogenemic women, 20 hirsute patients with normal total testosterone (total T), 18 patients with acne (normal total T), and 9 women with adrenogenital syndrome (AGS). INTERVENTION(S) Blood samples were taken by venipuncture. MAIN OUTCOME MEASURE(S) Serum concentrations of free T. RESULT(S) Mean free-T levels determined by UFT amounted to 5-6 pg/mL in most groups, except in patients with hyperandrogenemia (8.3 pg/mL) or AGS (10.7 pg/mL) and in women using OC (1.9 pg/mL). The values were twofold to fourfold and threefold to sevenfold higher than those determined with the RIAs. The proportion of free T as determined by UFT was 0.9-1.2% of total T and was 0.55% during OC treatment. The presence of 10 ng/mL of LNG or NET increased free-T levels by only 13%. CONCLUSION(S) Serum free-T levels determined with RIA are much lower than those measured with the UFT. The ratio between the UFT and RIA values may vary depending on the endocrine status. In women with normal or elevated sex hormone-binding globulin levels, nortestosterone derivatives increase free T levels only slightly.
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Affiliation(s)
- A Gruschke
- Department of Obstetrics and Gynecology, J. W. Goethe University, Frankfurt am Main, Germany
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20
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Findlay JW, Smith WC, Lee JW, Nordblom GD, Das I, DeSilva BS, Khan MN, Bowsher RR. Validation of immunoassays for bioanalysis: a pharmaceutical industry perspective. J Pharm Biomed Anal 2000; 21:1249-73. [PMID: 10708409 DOI: 10.1016/s0731-7085(99)00244-7] [Citation(s) in RCA: 376] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Immunoassays are bioanalytical methods in which quantitation of the analyte depends on the reaction of an antigen (analyte) and an antibody. Although applicable to the analysis of both low molecular weight xenobiotic and macromolecular drugs, these procedures currently find most consistent application in the pharmaceutical industry to the quantitation of protein molecules. Immunoassays are also frequently applied in such important areas as the quantitation of biomarker molecules which indicate disease progression or regression, and antibodies elicited in response to treatment with macromolecular therapeutic drug candidates. Currently available guidance documents dealing with the validation of bioanalytical methods address immunoassays in only a limited way. This review highlights some of the differences between immunoassays and chromatographic assays, and presents some recommendations for specific aspects of immunoassay validation. Immunoassay calibration curves are inherently nonlinear, and require nonlinear curve fitting algorithms for best description of experimental data. Demonstration of specificity of the immunoassay for the analyte of interest is critical because most immunoassays are not preceded by extraction of the analyte from the matrix of interest. Since the core of the assay is an antigen-antibody reaction, immunoassays may be less precise than chromatographic assays; thus, criteria for accuracy (mean bias) and precision, both in pre-study validation experiments and in the analysis of in-study quality control samples, should be more lenient than for chromatographic assays. Application of the SFSTP (Societe Francaise Sciences et Techniques Pharmaceutiques) confidence interval approach for evaluating the total error (including both accuracy and precision) of results from validation samples is recommended in considering the acceptance/rejection of an immunoassay procedure resulting from validation experiments. These recommendations for immunoassay validation are presented in the hope that their consideration may result in the production of consistently higher quality data from the application of these methods.
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Affiliation(s)
- J W Findlay
- Metabolism and Safety Evaluation, Searle, Skokie, IL 60077, USA
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21
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Lammers P, Blumenthal PD, Huggins GR. Developments in contraception: a comprehensive review of Desogen (desogestrel and ethinyl estradiol). Contraception 1998; 57:1S-27S. [PMID: 9673846 DOI: 10.1016/s0010-7824(98)00030-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- P Lammers
- Organon Inc., West Orange, New Jersey 07052, USA
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22
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Saano V, Glue P, Banfield CR, Reidenberg P, Colucci RD, Meehan JW, Haring P, Radwanski E, Nomeir A, Lin CC. Effects of felbamate on the pharmacokinetics of a low-dose combination oral contraceptive. Clin Pharmacol Ther 1995; 58:523-31. [PMID: 7586946 DOI: 10.1016/0009-9236(95)90172-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of felbamate on the pharmacokinetics of a low-dose combination oral contraceptive containing 30 micrograms ethinyl estradiol and 75 micrograms gestodene were assessed in a randomized, double-blind, placebo-controlled parallel-group study in healthy premenopausal female volunteers established in a regimen of oral contraceptive use. They received either placebo or 2400 mg/day felbamate from midcycle (day 15) to midcycle (day 14) of two consecutive oral contraceptive cycles (months 1 and 2). Pharmacokinetic assessments of ethinyl estradiol and gestodene were performed on day 14 of both cycles. To determine whether ovulation occurred, plasma progesterone and urinary luteinizing hormone levels were measured, and diaries recording vaginal bleeding were kept. Felbamate treatment resulted in a significant 42% decrease in gestodene area under the plasma concentration-time curve (0 to 24 hours) (p = 0.018) compared with baseline, whereas a minor but not clinically relevant effect was observed on the pharmacokinetic parameters of ethinyl estradiol. There were no changes in the pharmacokinetics of ethinyl estradiol or gestodene after placebo treatment. No volunteer showed hormonal evidence of ovulation; however, one volunteer reported the onset of intermenstrual bleeding during felbamate treatment. Because of the effect of felbamate on the pharmacokinetics of gestodene and the report of intermenstrual bleeding, it is possible that the contraceptive efficacy of low-dose combination oral contraceptives may be adversely affected during felbamate treatment.
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Affiliation(s)
- V Saano
- Department of Pharmacology, University of Kuopio
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23
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Kuhnz W, Louton T, Hümpel M, Back DJ, Zamah NM. Influence of high doses of vitamin C on the bioavailability and the serum protein binding of levonorgestrel in women using a combination oral contraceptive. Contraception 1995; 51:111-6. [PMID: 7750288 DOI: 10.1016/0010-7824(94)00016-p] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The absence of an effect of high oral doses of vitamin C on the systemic availability of ethinylestradiol in women using a levonorgestrel-containing combination oral contraceptive (0.15 mg levonorgestrel and 0.03 mg ethinylestradiol) was demonstrated in a recent study. However, it is conceivable that the oral administration of gram quantities of vitamin C could also interfere with the sulfation of levonorgestrel (LNG) metabolites during phase II biotransformation, because sulfates represent a major part of the conjugated metabolites of LNG in the serum. This possible interaction was investigated in the aforementioned study, comparing Cmax and AUC(0-12h) values of LNG on the first and 15th day of two successive treatment cycles with and without co-medication of vitamin C. In addition, the serum protein binding of LNG and the concentration of the binding proteins SHBG and CBG were compared between both treatments. Corresponding parameters obtained during treatment with the oral contraceptive alone and during co-administration of vitamin C were evaluated statistically for possible differences. No effect of vitamin C was observed for any of the parameters investigated. Thus, the repeated oral administration of gram quantities of vitamin C does not impair the sulfation of hydroxylated metabolites of LNG. There was also no observable effect on the serum protein binding of LNG and the concentrations of SHBG and CBG in the serum. The results obtained in this study population (American women) for LNG are in good agreement with those obtained from a previous study in European women, who had taken a combination oral contraceptive containing the same doses of LNG and ethinylestradiol.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering Aktiengesellschaft, Berlin, Germany
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24
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Kuhnz W, Staks T, Jütting G. Pharmacokinetics of levonorgestrel and ethinylestradiol in 14 women during three months of treatment with a tri-step combination oral contraceptive: serum protein binding of levonorgestrel and influence of treatment on free and total testosterone levels in the serum. Contraception 1994; 50:563-79. [PMID: 7705098 DOI: 10.1016/0010-7824(94)90014-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The pharmacokinetics of levonorgestrel (LNG) and ethinylestradiol (EE2) were determined in 14 healthy women (age 18 to 27 years) during a treatment period of three months with a tri-step combination oral contraceptive (Triquilar). Prior to this treatment period, the same women received a single administration of a coated tablet containing 0.125 mg LNG together with 0.03 mg EE2. There was a washout phase of one week between both treatments. Following single dose administration, a mean terminal half-life of 22 h was observed for LNG. The total clearance was 1.0 ml x min-1 x kg-1 and the volume of distribution was 128 l. During a treatment cycle, LNG levels in the serum accumulated by a factor of about four 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 LNG at the end of treatment cycles one and three: reduced total (0.5 ml x min-1 x kg-1) and free clearance (50 ml x min-1 x kg-1) and a reduced volume of distribution (52 l). A concomitant increase in the SHBG concentrations by a factor of two as compared to pretreatment values was observed during treatment and appeared to be mainly responsible for the changes in the pharmacokinetics of LNG. Marked changes were also seen for the serum protein binding of LNG. After single dose administration, the free fraction of LNG was 1.4% and the fractions bound to SHBG and albumin were 55.0% and 43.6%, respectively. At the end of cycle one, the free fraction was only 1.0% and the fractions bound to SHBG and albumin were 69.4% and 30.0%, respectively. There was no difference in corresponding pharmacokinetic parameters and in the serum protein binding of LNG 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 331.2 and 369.6 pg x ml-1 x h, respectively, which corresponds to an about 11-24% increase as compared to single dose administration, where an AUC(0-4h) value of 298.3 pg x ml-1 x h was found. Total and free testosterone concentrations decreased during treatment cycles one and three by about 41% and 55%, respectively, compared with the corresponding values measured prior to treatment.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering Aktiengesellschaft, Berlin, FRG
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25
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Tacey RL, Harman WJ, Kelly LL. Development of a highly sensitive and specific assay for plasma ethinylestradiol using combined extraction, liquid chromatography and radioimmunoassay. J Pharm Biomed Anal 1994; 12:1303-10. [PMID: 7841227 DOI: 10.1016/0731-7085(94)00065-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A highly sensitive and specific assay for ethinylestradiol (EE2) in human plasma was developed. The assay procedure combined solid-phase extraction of plasma samples, isolation of extracted EE2 by liquid chromatography (LC), and radioimmunoassay. Samples were extracted to remove polar plasma constituents and steroid binding proteins. Chromatography was employed to separate EE2 from other steroids that were candidates for assay cross-reactivity. The radioimmunoassay was shown to be sensitive (lower limit of quantitation = 2 pg ml-1 EE2 in plasma) and accurate (mean accuracy = 102%). Recovery of EE2 through extraction and LC steps was 76.1 +/- 4.5% (mean +/- SD; n = 42). Overall assay intra- and inter-assay coefficients of variation were 3.6 and 8.9%, respectively. The analyte was stable in assay buffer and assay accuracy was influenced minimally by four sample freeze-thaw cycles. This assay protocol enables the precise monitoring of low circulating levels of EE2, a prominent and potent synthetic oestrogen.
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Affiliation(s)
- R L Tacey
- Chemistry Department, Hazleton Washington, Inc., Vienna, VA 22182-1699
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26
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Hammond GL, Bocchinfuso WP, Orava M, Smith CL, van den Ende A, van Enk A. Serum distribution of two contraceptive progestins: 3-ketodesogestrel and gestodene. Contraception 1994; 50:301-18. [PMID: 7813219 DOI: 10.1016/0010-7824(94)90018-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A cross-over study of two oral contraceptive formulations, containing 30 micrograms ethinylestradiol in combination with 150 micrograms desogestrel (Marvelon) or 75 micrograms gestodene (Femovan), has been performed to compare the serum distribution and pharmacokinetics of gestodene and the active metabolite of desogestrel, namely 3-ketodesogestrel. Serum concentrations of both sex hormone-binding globulin (SHBG) and corticosteroid-binding globulin (CBG) were also measured and were increased more than 3-fold and 2-fold, respectively, on day 21 of the treatment cycle, with no statistically significant difference between treatment groups. In addition, 35 days after ingestion of either oral contraceptive had ceased, the serum SHBG and CBG concentrations were similar to the pretreatment values. During treatment cycles, increased serum SHBG levels were associated with a redistribution of 3-ketodesogestrel and gestodene such that the non-protein-bound (NPB) and albumin-bound fractions were reduced in concert with an increase in the relative proportions bound to SHBG. The proportion of gestodene bound to SHBG was consistently higher than that observed for 3-ketodesogestrel, and this undoubtedly reflects the higher affinity of SHBG for gestodene (Kd = 1.2 nM at 37 degrees C) when compared to 3-ketodesogestrel (Kd = 4.7 nM at 37 degrees C). It also probably accounts, in part, for the much higher total serum levels of gestodene (8.58 nmol/L) when compared to 3-ketodesogestrel (2.37 nmol/L) during the treatment cycles. Consequently, the absolute amounts of NPB, non-SHBG-bound, and SHBG-bound gestodene are significantly higher than those measured for 3-ketodesogestrel. It is concluded that ethinylestradiol-induced increases in serum SHBG levels during treatment with Marvelon or Femovan, influenced the distribution and total amount of 3-ketodesogestrel and gestodene in serum, respectively, and that this, combined with the higher affinity of SHBG for gestodene, results in a greater amount of bioavailable gestodene compared to 3-ketodesogestrel, despite the smaller dose of gestodene administered.
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Affiliation(s)
- G L Hammond
- Department of Obstetrics and Gynecology, University of Western Ontario, London, Canada
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27
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Kuhnz W, Schütt B, Woloszczak R. Influence of changes in the concentration of sex hormone-binding globulin in human serum on the protein binding of the contraceptive steroids levonorgestrel, 3-keto-desogestrel and gestodene. J Steroid Biochem Mol Biol 1994; 48:573-80. [PMID: 8180122 DOI: 10.1016/0960-0760(94)90211-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The serum protein binding of levonorgestrel, gestodene and 3-keto-desogestrel has been determined during several clinical studies with different oral contraceptive formulations and one in vitro study. The results of these studies were combined in order to assess the relation between changes in the concentration of sex hormone-binding globulin (SHBG) and the effect on the free fraction of the progestins as well as on their distribution with respect to the binding proteins albumin and SHBG. Although marked differences in protein binding were seen for the three progestins at low concentrations of SHBG, these differences became less pronounced at high levels of SHBG which were reached during established oral contraceptive therapy. A nonlinear relation could be shown for either the free or the protein-bound fraction of the progestins and the concentration of SHBG in the serum, respectively.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering AG, Berlin, Germany
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28
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Archer DF, Timmer CJ, Lammers P. Pharmacokinetics of a triphasic oral contraceptive containing desogestrel and ethinyl estradiol. Fertil Steril 1994; 61:645-51. [PMID: 8150105 DOI: 10.1016/s0015-0282(16)56640-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To demonstrate that pharmacokinetic measurements were made at steady state. Subsequently, dose proportionality for desogestrel and ethinyl E2 kinetics were demonstrated. DESIGN Open-label, noncomparative study. SETTING Healthy volunteers in an academic research environment. PARTICIPANTS Twenty white women who were 19 to 32 years old were solicited via an advertisement. Nineteen of the 20 women completed the study. INTERVENTIONS Study medication consisted of three cycles of a triphasic oral contraceptive containing desogestrel and ethinyl E2. Blood samples were taken at baseline and during cycle 3 between -48 and 24 hours on days 1, 7, 14, and 21, with additional sampling times on day 21 at 48, 60, and 72 hours. MAIN OUTCOME MEASURES Serum concentrations of 3-keto-desogestrel and ethinyl E2. RESULTS Evaluation of the trough serum levels indicated that a steady state of 3-keto-desogestrel had been reached. Statistical analysis on the Cmax, area under the curve (AUC), and Css,min indicated dose proportionality for the administered desogestrel. Ethinyl E2 serum levels obtained at the same time points also reflected steady state levels and showed minimal variability. The statistical analysis on Cmax, AUC, Css,min, and Tmax indicated that the pharmacokinetics of ethinyl E2 on days 7, 14, and 21 were not statistically significantly different, indicating dose equivalency. CONCLUSIONS Steady state of 3-keto-desogestrel is reached after each of the three phases and the pharmacokinetics are dose proportional. After reaching steady state, the pharmacokinetics of ethinyl E2 remain constant over time.
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Affiliation(s)
- D F Archer
- Jones Institute for Reproductive Medicine, Eastern Virginia Medical School, Norfolk 23507-1912
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29
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Kuhnz W, Baumann A, Staks T, Dibbelt L, Knuppen R, Jütting G. Pharmacokinetics of gestodene and ethinylestradiol in 14 women during three months of treatment with a new tri-step combination oral contraceptive: serum protein binding of gestodene and influence of treatment on free and total testosterone levels in the serum. Contraception 1993; 48:303-22. [PMID: 8222659 DOI: 10.1016/0010-7824(93)90077-k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
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.
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Affiliation(s)
- W Kuhnz
- Institut für Pharmakokinetik, Schering Aktiengesellschaft, Berlin, FRG
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30
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Abstract
A synthetic form of desogestrel, a gonane progestin, was developed because desogestrel's enhanced selectivity eliminates adverse, androgen-dependent, metabolic effects at contraceptive doses. Desogestrel is rapidly and completely metabolized in the liver and gut wall to 3-keto-desogestrel, which is the active metabolite mediating the progestin effects. Because of its unique 11-methylene side chain, desogestrel cannot be metabolized to any other known progestin, nor is desogestrel a naturally occurring metabolite of any other progestin. The pharmacokinetic parameters of 3-keto-desogestrel are generally comparable with those of levonorgestrel and norethindrone. Therefore any differences in pharmacologic activities must be attributed to differences in intrinsic activities. Unlike gestodene, 3-keto-desogestrel has a lower affinity for sex hormone-binding globulin, which results in markedly lower plasma levels after administration. After oral administration of 150 micrograms of desogestrel, plasma levels are less than half the levels of gestodene after an oral dose of 75 micrograms.
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Affiliation(s)
- H D McClamrock
- Department of Obstetrics and Gynecology, University of Maryland School of Medicine, Baltimore 21201
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31
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Kuhnz W, al-Yacoub G, Fuhrmeister A. Pharmacokinetics of levonorgestrel in 12 women who received a single oral dose of 0.15 mg levonorgestrel and, after a washout phase, the same dose during one treatment cycle. Contraception 1992; 46:443-54. [PMID: 1458891 DOI: 10.1016/0010-7824(92)90148-m] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The pharmacokinetics of levonorgestrel (LNG) was determined in 12 healthy women (age 21 to 33 years), following single dose administration of 0.15 mg LNG. The same preparation was also administered during one treatment cycle after a washout phase of 1 week. After single dose administration, maximum concentrations of LNG in the serum were 4.3 +/- 1.3 ng/ml. Post maximum drug levels declined biphasically with half-lives of 0.6 +/- 0.2 h and 13.9 +/- 3.2 h, respectively. The clearance was calculated to be 1.5 +/- 0.6 ml x min-1 x kg-1. The free fraction of LNG was 1.1 +/- 0.1% and the fractions bound to SHBG and albumin were 61.8 +/- 6.7% and 37.1 +/- 6.7%, respectively. There was a gradual decrease in serum trough levels of LNG from about 0.5 to 0.3 ng/ml during the cycle, and a concomitant decrease in SHBG concentrations in the serum by about 50%. Serum protein binding of LNG changed markedly during the treatment cycle. The free fraction increased to a value of 1.7 +/- 0.3%, the SHBG-bound fraction decreased to 42.0 +/- 11.4% and the albumin-bound fraction increased to 56.4 +/- 11.2%. Total serum clearance increased during the same time period from a mean value of 1.5 to about 2.5 ml x min-1 x kg-1. The clearance of unbound LNG, however, remained unchanged. An examination of the free LNG concentrations revealed the same time course of LNG trough levels during the cycle as the simulated curve. This was derived from the pharmacokinetic parameters which were obtained after single dose administration. Thus, the present study showed that the pharmacokinetics of LNG can be fully explained on the basis of single dose pharmacokinetics and the changes in serum protein binding which were caused by a reduction of SHBG levels in the serum during chronic treatment with LNG.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering AG, Berlin, Germany
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Kuhnz W, al-Yacoub G, Fuhrmeister A. Pharmacokinetics of levonorgestrel and ethinylestradiol in 9 women who received a low-dose oral contraceptive over a treatment period of 3 months and, after a wash-out phase, a single oral administration of the same contraceptive formulation. Contraception 1992; 46:455-69. [PMID: 1458892 DOI: 10.1016/0010-7824(92)90149-n] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The pharmacokinetics of levonorgestrel (LNG) and ethinylestradiol (EE2) were determined in 9 healthy women (age 23 to 42 years), during a treatment period of three months with a low-dose oral contraceptive, containing 0.15 mg LNG together with 0.03 mg EE2 (Microgynon). After a wash-out period of 3 months, 8 of these women received a single administration of the same formulation. The results showed that there was an increase in serum trough levels of LNG, reaching steady-state in the second half of each treatment cycle. The LNG levels achieved were about 3 to 4 times higher than anticipated on the basis of single dose administration. At the end of treatment cycles one and three, the terminal half-life of LNG was in the range of 24-26 h, while a mean value of 20 h was observed following single dose administration. An EE2-induced increase in the SHBG concentration of about 50% as compared to pretreatment values was observed during a treatment cycle. Pretreatment values were reached following the drug-free interval of 7 days between two cycles. After single dose administration, the free fraction of LNG was 1.3 +/- 0.2% and the fractions bound to SHBG and albumin were 64.1 +/- 4.2% and 34.6 +/- 4.0%, respectively. Serum protein binding of LNG did not change during chronic treatment. An about 50% reduction in total and unbound clearance of LNG was observed during chronic treatment, as compared to single dose administration. Increased SHBG binding capacity and a reduced hepatic metabolic capacity were discussed as possible causes of accumulating LNG concentrations in the serum. On the last day of treatment cycles one and three, the AUC(0-24h) values of EE2 were 728 +/- 314 and 778 +/- 318 pg x ml-1 x h, respectively, and were in keeping with data reported from others.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering AG, Berlin, Germany
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Kuhnz W, Gansau C, Fuhrmeister A. Pharmacokinetics of gestodene in 12 women who received a single oral dose of 0.075 mg gestodene and, after a wash-out phase, the same dose during one treatment cycle. Contraception 1992; 46:29-40. [PMID: 1424621 DOI: 10.1016/0010-7824(92)90129-h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The pharmacokinetics of gestodene (GEST) was determined in 12 healthy women (age 22 to 34 years), following single dose administration of 0.075 mg GEST. The same preparation was also administered during one treatment cycle after a wash-out phase of 1 week. After single dose administration, maximum concentrations of GEST in the serum were 4.9 +/- 2.5 ng/ml. Post maximum drug levels declined biphasically with half-lives of 0.2 +/- 0.2 h and 14.9 +/- 6.7 h, respectively. The apparent clearance was calculated to be 0.8 +/- 0.4 ml x min-1 x kg-1. The free fraction of GEST was 1.3 +/- 0.3% and the fractions bound to SHBG and albumin were 64.3 +/- 10.7% and 34.4 +/- 10.4%, respectively. The results showed that there was a gradual decrease in serum trough levels of GEST during the cycle, due to a concomitant and equally high decrease in SHBG concentrations in the serum of about 26%. At the end of one treatment cycle, the free fraction of GEST increased to 1.8 +/- 0.5%, the SHBG-bound fraction decreased to 57.0 +/- 10.2% and the albumin-bound fraction increased to 41.3 +/- 9.9%. Total serum clearance increased during the same time period from a mean value of 0.8 to about 1.2 ml x min-1 x kg-1. The clearance of unbound GEST, however, remained unchanged. An examination of the free GEST concentrations revealed the same time course of GEST trough levels during the cycle as the simulated curve. This was derived from the pharmacokinetic parameters which were obtained after single dose administration. Thus, the present study showed that the pharmacokinetics of GEST can be fully explained on the basis of single dose pharmacokinetics and the changes in serum protein binding which were caused by a reduction of SHBG levels in the serum during chronic treatment with GEST. There was no evidence of GEST inhibiting its own metabolism.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering AG Berlin, Germany
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Kuhnz W, Sostarek D, Gansau C, Louton T, Mahler M. Single and multiple administration of a new triphasic oral contraceptive to women: pharmacokinetics of ethinyl estradiol and free and total testosterone levels in serum. Am J Obstet Gynecol 1991; 165:596-602. [PMID: 1892184 DOI: 10.1016/0002-9378(91)90292-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Ethinyl estradiol is part of almost every combined oral contraceptive, and its pharmacokinetic characteristics have been thoroughly investigated in numerous studies. However, little is known about its pharmacokinetics during long-term administration, as compared with single-dose administration. In this study 10 women received a triphasic formulation that contained ethinyl estradiol together with the progestin gestodene over one treatment cycle. Mean area under the curve values of ethinyl estradiol were significantly higher on the last treatment day, as compared with the corresponding values obtained from the same women after single-dose administration. However, the observed increase in area under the curve was within the range of pharmacokinetic accumulation, to be expected on the basis of dosing interval and terminal half-life. Another point of interest was the effect of the triphasic preparation on testosterone concentrations in serum. Both total and free testosterone levels were suppressed by about 60% as compared with pretreatment values, and there was no correlation with corresponding sex hormone-binding globulin levels in the serum.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering AG, Berlin, Federal Republic of Germany
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Dibbelt L, Knuppen R, Jütting G, Heimann S, Klipping CO, Parikka-Olexik H. Group comparison of serum ethinyl estradiol, SHBG and CBG levels in 83 women using two low-dose combination oral contraceptives for three months. Contraception 1991; 43:1-21. [PMID: 1825969 DOI: 10.1016/0010-7824(91)90122-v] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Serum ethinyl estradiol (EE2), sex hormone-binding globulin (SHBG) and corticosteroid-binding globulin (CBG) concentrations were studied in healthy young women randomly allocated to one of two low-dose combination oral contraceptives containing 30 micrograms EE2 and either 75 micrograms gestodene (F) or 150 micrograms desogestrel (M) per unit. There was either no (formerly non-pill users) or one (pill users) wash-out cycle before the study started with a pill-free pretreatment cycle in which the hormone status and basal SHBG and CBG levels were measured. Treatment was for three months. During treatment cycles 1 and 3, there were three test days each. Seven serum samples were obtained up to four hours and one sample 24 hours after intake of the first, tenth and the last (21st) pill. Additional samples were taken prior to morning ingestion of pills 5 and 15. For each individual and each test day, a representative serum pool has been constructed for SHBG and CBG analysis. EE2 concentrations were analyzed in all individual samples by means of a specific and sensitive RIA using anti-EE2-6 beta-CMO-BSA antiserum. Area under the curves (AUC) up to 4 and 24 hours, Cmax and tmax were evaluated and compared between the two treatment groups (n = 40 for F, n = 43 for M). SHBG and CBG concentrations were measured using commercially available immunoassay kits. Groups were large enough to detect a difference in group means of 75% of one standard deviation (alpha = 0.05, 1-beta = 0.9) of target variables, which is equivalent to 28 pg EE2/ml for Cmax, 69 pg.h.ml-1 for AUCEE2 0-4h, 257 pg.h.ml-1 for AUCEE2 0-24h, 39 nmol/l SHBG and 13.4 micrograms CBG/ml. Results clearly demonstrate that there were no differences between the two treatment groups in any of the target variables at any of the six test days distributed over a three-month period. Mean SHBG and CBG pretreatment levels of about 70 nmol/l and 37 micrograms/ml, respectively, increased to about 210 nmol/l and 88 micrograms/ml during the first treatment cycle and to about 230 nmol/l and 93 micrograms/ml during the third treatment cycle. Whereas the time of maximum EE2 serum levels did not differ significantly between test days, Cmax, AUCEE2 0-4h and AUCEE2 0-24h values increased by 30-35% or 40-50%, respectively, when test days 10 and 21 were compared to test day 1. Similar results were found for the third treatment cycle.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- L Dibbelt
- Institut für Biochemische Endokrinologie, Medizinische Universität zu Lübeck, FRG
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Kuhnz W. Pharmacokinetics of the contraceptive steroids levonorgestrel and gestodene after single and multiple oral administration to women. Am J Obstet Gynecol 1990; 163:2120-7. [PMID: 2124087 DOI: 10.1016/0002-9378(90)90551-h] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Little is known about the pharmacokinetics of the two progestins levonorgestrel and gestodene during long-term administration compared with single-dose pharmacokinetics. The predictive value of single-dose administration for the pharmacokinetic behavior of a progestin during long-term treatment was investigated for two triphasic oral contraceptives. One contained levonorgestrel and the other gestodene, each in combination with ethinyl estradiol. In eight Japanese women who received the levonorgestrel-containing formulation over a treatment cycle, steady-state trough levels of levonorgestrel were higher than those obtained by computer simulation based on single-dose administration. An analogous observation was made in a group of 10 white women who received the gestodene-containing formulation. A close correlation between gestodene and sex hormone-binding globulin concentrations was demonstrated for eight subjects; the other two patients already had initially high sex hormone-binding globulin levels. Ethinyl estradiol-induced production of sex hormone-binding globulin seems to be a major factor that contributes to the accumulation of the two progestins in the plasma. Computer simulation, based on single-dose pharmacokinetics, allows an estimation of this contribution.
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Affiliation(s)
- W Kuhnz
- Research Laboratories, Schering AG, Berlin, West Germany
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Jung-Hoffman C, Kuhl H. Pharmacokinetics and pharmacodynamics of oral contraceptive steroids: factors influencing steroid metabolism. Am J Obstet Gynecol 1990; 163:2183-97. [PMID: 2147819 DOI: 10.1016/0002-9378(90)90560-t] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The time-dependent alterations in the serum concentrations of ethinyl estradiol, gestodene, and 3-keto-desogestrel during treatment with 30 micrograms of ethinyl estradiol + 75 micrograms of gestodene or 30 micrograms of ethinyl estradiol + 150 micrograms of desogestrel were investigated during 12 months. The levels of gestodene and 3-keto-desogestrel increased between days 1 and 21 of each cycle, reaching maximal levels during the third and sixth cycles. The serum concentrations of gestodene were fourfold to fivefold higher than those of 3-keto-desogestrel. The ethinyl estradiol levels increased significantly between days 1 and 10 during each cycle and were significantly higher by 70% during intake of ethinyl estradiol/gestodene compared with ethinyl estradiol/desogestrel, although the dose was identical. Intake of gestodene, in addition to 35 micrograms of ethinyl estradiol + 2 mg of cyproterone acetate, caused a rise in ethinyl estradiol levels. During treatment with ethinyl estradiol/gestodene and an additional 150 micrograms of levonorgestrel, there was a continuous increase in gestodene levels, although sex hormone-binding globulin level did not change. During treatment with 30 or 35 micrograms of ethinyl estradiol and 75 micrograms of gestodene, 150 micrograms of desogestrel, or 2 mg of cyproterone acetate, there were large intraindividual and interindividual variations in the steroid levels and ratios of estrogen: progestogen levels. There was no correlation with the occurrence of intermenstrual bleedings. It is concluded that ethinyl estradiol and nortestosterone derivatives may inhibit steroid-metabolizing enzymes in the liver, which results in a rise in the serum levels of contraceptive steroids. The cause of the large intraindividual variations is as yet unknown, but it is probably from changes in steroid metabolism.
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Affiliation(s)
- C Jung-Hoffman
- Department of Obstetrics and Gynecology, J. W. Goethe University, Frankfurt, Federal Republic of Germany
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Täuber U, Kuhnz W, Hümpel M. Pharmacokinetics of gestodene and ethinyl estradiol after oral administration of a monophasic contraceptive. Am J Obstet Gynecol 1990; 163:1414-20. [PMID: 2220966 DOI: 10.1016/0002-9378(90)91358-j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The pharmacokinetic and protein-binding properties of gestodene and ethinyl estradiol have been investigated after single and multiple dosing in several studies in 83 healthy, young women. After oral administration, gestodene is completely absorbed and bioavailable and exhibits dose-linear pharmacokinetics. During long-term pill use, serum levels of gestodene were four to five times higher than after single administration, showing a periodic increase from day 1 to day 10 during each cycle. Ultrafiltration studies revealed that 75.3% of total serum gestodene is bound to sex hormone-binding globulin, 24.1% is bound to albumin, and only 0.6% is not protein bound. Thus gestodene levels during steady state are explained by an increase in sex hormone binding-globulin as a result of concomitant administered ethinyl estradiol and a specific binding of gestodene to this protein. Serum levels of ethinyl estradiol during single and multiple administration were identical and were not different from those observed with another preparation containing 30 micrograms of ethinyl estradiol.
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Affiliation(s)
- U Täuber
- Research Laboratories, Schering AG, Berlin, West Germany
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