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158 result(s) for "Foidart, Jean Michel"
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Low Thrombin Generation in Users of a Contraceptive Containing Estetrol and Drospirenone
Abstract Objective To compare the impact on thrombin generation of the new combined oral contraceptive containing 15 mg estetrol and 3 mg drospirenone with ethinylestradiol (30 or 20 mcg) associated either with 150 mcg levonorgestrel or with 3 mg drospirenone. Methods Data were collected from the “E4/DRSP Endocrine Function, Metabolic Control and Hemostasis Study” (NCT02957630). Overall, the per-protocol set population included 24 subjects in the ethinylestradiol/levonorgestrel arm, 28 subjects in the ethinylestradiol/drospirenone arm, and 34 subjects in the estetrol/drospirenone arm. Thrombograms and thrombin generation parameters (lag time, peak, time to peak, endogenous thrombin potential, and mean velocity rate index) were extracted for each subject at baseline and after 6 cycles of treatment. Results After 6 cycles of treatment, ethinylestradiol-containing products arms show a mean thrombogram outside the upper limit of the reference range, that is the 97.5th percentile of all baseline thrombograms. On the other hand, the mean thrombogram of estetrol/drospirenone is within this reference interval. After 6 cycles of treatment, all thrombin generation parameters are statistically less affected by estetrol/drospirenone than ethinylestradiol-containing products. Conclusions In conclusion, an association of 15 mg estetrol with 3 mg drospirenone does not have an impact on thrombin generation compared with ethinylestradiol-containing products that, either associated with levonorgestrel or drospirenone, are able to increase the production of procoagulant factors and decrease the production of anticoagulant ones, shifting the patient to a prothrombotic state. Ethinylestradiol-containing products thus generate prothrombotic environments contrary to estetrol which demonstrates a neutral profile on hemostasis.
Estetrol: From Preclinical to Clinical Pharmacology and Advances in the Understanding of the Molecular Mechanism of Action
Estetrol (E4) is the most recently described natural estrogen. It is produced by the human fetal liver during pregnancy and its physiological function remains unclear. E4 is the estrogenic component of a recently approved combined oral contraceptive. It is also in development for use as menopausal hormone therapy. In the context of these developments, the pharmacological activity of E4, alone or in combination with a progestin, has been extensively characterized in preclinical models as well as in clinical studies in women of reproductive age and postmenopausal women. Despite the clinical benefits, the use of oral estrogens for contraception or menopause is also associated with unwanted effects, such as an increased risk of breast cancer and thromboembolic events, due to their impact on non-target tissues. Preclinical and clinical data for E4 point to a tissue-specific activity and a more selective pharmacological profile compared with other estrogens, including a low impact on the liver and hemostasis balance. This review summarizes the characterization of the pharmacological properties of E4 as well as recent advances made in the understanding of the molecular mechanisms of action driving its activity. How the unique mode of action and the different metabolism of E4 might support its favorable benefit–risk ratio is also discussed.
Critical Considerations in the Interpretation of Bone Turnover Marker Data in Hormonal Contraceptive Users. Comment on Tassi et al. Hormonal Contraception and Bone Metabolism: Emerging Evidence from a Systematic Review and Meta-Analysis of Studies on Post-Pubertal and Reproductive-Age Women. Pharmaceuticals 2025, 18, 61
In response to the recent meta-analysis by Tassi et al. on hormonal contraception and bone metabolism, we raise critical concerns regarding the interpretation of bone turnover markers as surrogates for bone mineral density (BMD). While bone turnover markers can offer early insights into bone remodeling, they do not directly predict long-term BMD changes, which require 12–24 months to detect. The assumption that equivalent percentage changes in bone formation and resorption markers reflect stable BMD is not supported by current evidence. Bone metabolism varies significantly across life stages, particularly during adolescence and early adulthood, when peak bone mass is still accruing—underscoring the need for age-specific analyses. Additionally, biomarker interpretation is limited by assay variability, inconsistent sampling protocols, and uncertain clinical implications, especially for formation markers. Mechanistically, estrogen supports bone integrity by inhibiting resorption and promoting formation; thus, combined hormonal contraceptives (CHCs) containing estrogen may help preserve bone health. In contrast, progestin-only methods can suppress endogenous estrogen production, potentially compromising skeletal development. We advocate for longitudinal studies incorporating both BMD and turnover markers, stratified by age and contraceptive formulation, to guide safer and more informed contraceptive choices that protect long-term bone health.
Human Chorionic Gonadotrophin: New Pleiotropic Functions for an “Old” Hormone During Pregnancy
Human chorionic gonadotrophin (hCG) is the first specific molecule synthesized by the embryo. hCG RNA is transcribed as early as the eight-cell stage, and the blastocyst produces the protein before its implantation. hCG in the uterine microenvironment binds with its cognate receptor, luteinizing hormone/choriogonadotropin receptor (LHCGR), on the endometrial surface. This binding stimulates leukemia inhibitory factor (LIF) production and inhibits interleukin-6 (IL-6) production by epithelial cells of the endometrium. These effects ensure essential help in the preparation of the endometrium for initial embryo implantation. hCG also effects angiogenic and immunomodulatory actions as reported in many articles by our laboratories and other ones. By stimulating angiogenesis and vasculogenesis, hCG provides the placenta with an adequate maternal blood supply and optimal embryo nutrition during the invasion of the uterine endometrium. The immunomodulatory properties of hCG are numerous and important for programming maternal immune tolerance toward the embryo. The reported effects of hCG on uterine NK, Treg, and B cells, three major cell populations for the maintenance of pregnancy, demonstrate the role of this embryonic signal as a crucial immune regulator in the course of pregnancy. Human embryo rejection for hCG-related immunological reasons has been studied in different ways, and a sufficient dose of hCG seems to be necessary to maintain maternal tolerance. Different teams have studied the addition of hCG in patients suffering from recurrent miscarriages or implantation failures. hCG could also have a beneficial or a negative impact on autoimmune diseases during pregnancy. In this review, we will discuss the immunological impacts of hCG during pregnancy and if this hormone might be used therapeutically.
Bleeding Patterns of Oral Contraceptives with a Cyclic Dosing Regimen: An Overview
Bleeding irregularities are one of the major reasons for discontinuation of oral contraceptives (OCs), and therefore clinicians need to set expectations during consultations. In this review we provide an overview of bleeding data of recently marketed cyclic combined OCs (COCs) and one progestin-only pill (POP). We evaluated data from phase 3 trials (≥12 months) used to gain regulatory approval. Overall, each type of OC has its own specific bleeding pattern. These patterns however were assessed by using different bleeding definitions, which hampers comparisons between products. In COCs, the estrogen balances the effects of the progestin on the endometrium, resulting in a regular bleeding pattern. However, this balance seems lost if a too low dose of ethinylestradiol (EE) (e.g., 10 µg in EE/norethindrone acetate 1 mg) is used in an attempt to lower the risk of venous thromboembolism. Replacement of EE by 17β-estradiol (E2) or E2 valerate could lead to suboptimal bleeding profile due to destabilization of the endometrium. Replacement of EE with estetrol (E4) 15 mg in the combination with drospirenone (DRSP) 3 mg is associated with a predictable and regular scheduled bleeding profile, while the POP containing DRSP 4 mg in a 24/4 regimen is associated with a higher rate of unscheduled and absence of scheduled bleeding than combined products.
Impact of Estetrol Combined with Drospirenone on Blood Coagulation and Fibrinolysis in Patients with Endometriosis: A Multicenter, Randomized, Open-Label, Active-Controlled, Parallel-Group Study
Venous thromboembolism is a serious safety concern in women using combined oral contraceptives; ethinyl estradiol (EE) is widely used as an estrogen. Estetrol (E4) is a native estrogen with selective tissue activity and exclusively produced by the fetal liver. This study used a multicenter, randomized, open-label, active-controlled, parallel-group design to evaluate the effects of E4 combined with drospirenone (DRSP) on coagulation and fibrinolysis in Japanese patients with endometriosis. Participants were randomized to receive either E4 15 mg/DRSP 3 mg or EE 20 µg/DRSP 3 mg for 12 weeks. E4/DRSP and EE/DRSP were administered orally once a day in a cyclic regimen, ie, 24-day active use followed by a 4-day hormone-free period, and a flexible extended regimen, respectively, and blood coagulation and fibrinolysis markers were measured. The effect on coagulation and fibrinolysis was considerably less in the E4/DRSP group than in the EE/DRSP group. Major anticoagulant proteins, protein S (free, total) and tissue factor pathway inhibitor (free), were reduced following EE/DRSP treatment. Consequently, thrombin generation determined by the activated protein C sensitivity ratio was increased by approximately 4-fold in the EE/DRSP group than in the E4/DRSP group. Eventually, the fibrinolysis cascade was triggered to compensate for disturbed coagulation, and D-dimer levels were 4.7-fold higher in the EE/DRSP group than in the E4/DRSP group. This study demonstrated that the effect of E4/DRSP on the blood coagulation and fibrinolysis cascades was significantly less than that of EE/DRSP in participants with endometriosis, a disease of women of advanced and reproductive age (jRCT2080225090, https://jrct.niph.go.jp/en-latest-detail/jRCT2080225090).
Comparison of Estetrol Exposure between Women and Mice to Model Preclinical Experiments and Anticipate Human Treatment
Estetrol (E4) is a natural estrogen with promising therapeutic applications in humans. The European Medicines Agency and the Food and Drug Administration have approved the use of 15 mg E4/3 mg drospirenone for contraceptive indication. Phase III clinical trials with 15–20 mg E4 for the relief of climacteric complaints are currently running. Relevant data from preclinical animal models are needed to characterize the molecular mechanisms and the pharmacological effects of E4 and possibly to reveal new therapeutic applications and to anticipate potential adverse effects. Therefore, it is important to design experimental procedures in rodents that closely mimic or anticipate human E4 exposure. In this study, we compared the effects of E4 exposure after acute or chronic administration in women and mice. Women who received chronic E4 treatment per os at a dose of 15 mg once daily reached a steady state within 6 to 8 days, with a mean plasma concentration of 3.20 ng/mL. Importantly, with subcutaneous, intraperitoneal or oral administration of E4 in mice, a stable concentration over time that would mimic human pharmacokinetics could not be achieved. The use of osmotic minipumps continuously releasing E4 for several weeks provided an exposure profile mimicking chronic oral administration in women. Measurements of the circulating concentration of E4 in mice revealed that the mouse equivalent dose necessary to mimic human treatment does not fit with the allometric prediction. In conclusion, this study highlights the importance of precise definition of the most appropriate dose and route of administration to utilize when developing predictive preclinical animal models to mimic or anticipate specific human treatment.
A Membrane-Type-1 Matrix Metalloproteinase (MT1-MMP) – Discoidin Domain Receptor 1 Axis Regulates Collagen-Induced Apoptosis in Breast Cancer Cells
During tumour dissemination, invading breast carcinoma cells become confronted with a reactive stroma, a type I collagen-rich environment endowed with anti-proliferative and pro-apoptotic properties. To develop metastatic capabilities, tumour cells must acquire the capacity to cope with this novel microenvironment. How cells interact with and respond to their microenvironment during cancer dissemination remains poorly understood. To address the impact of type I collagen on the fate of tumour cells, human breast carcinoma MCF-7 cells were cultured within three-dimensional type I collagen gels (3D COL1). Using this experimental model, we have previously demonstrated that membrane type-1 matrix metalloproteinase (MT1-MMP), a proteinase overexpressed in many aggressive tumours, promotes tumour progression by circumventing the collagen-induced up-regulation of BIK, a pro-apoptotic tumour suppressor, and hence apoptosis. Here we performed a transcriptomic analysis to decipher the molecular mechanisms regulating 3D COL1-induced apoptosis in human breast cancer cells. Control and MT1-MMP expressing MCF-7 cells were cultured on two-dimensional plastic plates or within 3D COL1 and a global transcriptional time-course analysis was performed. Shifting the cells from plastic plates to 3D COL1 activated a complex reprogramming of genes implicated in various biological processes. Bioinformatic analysis revealed a 3D COL1-mediated alteration of key cellular functions including apoptosis, cell proliferation, RNA processing and cytoskeleton remodelling. By using a panel of pharmacological inhibitors, we identified discoidin domain receptor 1 (DDR1), a receptor tyrosine kinase specifically activated by collagen, as the initiator of 3D COL1-induced apoptosis. Our data support the concept that MT1-MMP contributes to the inactivation of the DDR1-BIK signalling axis through the cleavage of collagen fibres and/or the alteration of DDR1 receptor signalling unit, without triggering a drastic remodelling of the transcriptome of MCF-7 cells.
Safety and efficacy of tibolone in breast-cancer patients with vasomotor symptoms: a double-blind, randomised, non-inferiority trial
Vasomotor symptoms and bone loss are complications frequently induced by adjuvant treatment for breast cancer. Tibolone prevents both side-effects, but its effect on cancer recurrence is unknown. The aim of this study was to show non-inferiority of tibolone to placebo regarding risk of recurrence in breast-cancer patients with climacteric complaints. Between July 11, 2002, and Dec 20, 2004, women surgically treated for a histologically confirmed breast cancer (T 1–3N 0–2M 0) with vasomotor symptoms were randomly assigned to either tibolone 2·5 mg daily or placebo at 245 centres in 31 countries. Randomisation was done by use of a centralised interactive voice response system, stratified by centre, with a block size of four. The primary endpoint was breast-cancer recurrence, including contralateral breast cancer, and was analysed in the intention-to-treat (ITT) and per-protocol populations; the margin for non-inferiority was set as a hazard ratio of 1·278. This study is registered with ClinicalTrials.gov, number NCT00408863. Of the 3148 women randomised, 3098 were included in the ITT analysis (1556 in the tibolone group and 1542 in the placebo group). Mean age at randomisation was 52·7 years (SD 7·3) and mean time since surgery was 2·1 years (SD 1·3). 1792 of 3098 (58%) women were node positive and 2185 of 3098 (71%) were oestrogen-receptor positive. At study entry, 2068 of 3098 (67%) women used tamoxifen and 202 of 3098 (6·5%) women used aromatase inhibitors. The mean daily number of hot flushes was 6·4 (SD 5·1). After a median follow-up of 3·1 years (range 0·01–4·99), 237 of 1556 (15·2%) women on tibolone had a cancer recurrence, compared with 165 of 1542 (10·7%) on placebo (HR 1·40 [95% CI 1·14–1·70]; p=0·001). Results in the per-protocol population were similar (209 of 1254 [16·7%] women in the tibolone group had a recurrence vs 138 of 1213 [11·4%] women in the placebo group; HR 1·44 [95% CI 1·16–1·79]; p=0·0009). Tibolone was not different from placebo with regard to other safety outcomes, such as mortality (72 patients vs 63 patients, respectively), cardiovascular events (14 vs 10, respectively), or gynaecological cancers (10 vs 10, respectively). Vasomotor symptoms and bone-mineral density improved significantly with tibolone, compared with placebo. Tibolone increases the risk of recurrence in breast cancer patients, while relieving vasomotor symptoms and preventing bone loss. Schering-Plough (formerly NV Organon, Oss, Netherlands).
Estetrol Combined to Progestogen for Menopause or Contraception Indication Is Neutral on Breast Cancer
Given the unequivocal benefits of menopause hormone therapies (MHT) and combined oral contraceptives (COC), there is a clinical need for new formulations devoid of any risk of breast cancer promotion. Accumulating data from preclinical and clinical studies support that estetrol (E4) is a promising natural estrogen for MHT and COC. Nevertheless, we report here that E4 remains active on the endometrium, even under a dose that is neutral on breast cancer growth and lung metastasis dissemination. This implies that a progestogen should be combined with E4 to protect the endometrium of non-hysterectomized women from hyperplasia and cancer. Through in vivo observations and transcriptomic analyses, our work provides evidence that combining a progestogen to E4 is neutral on breast cancer growth and dissemination, with very limited transcriptional impact. The assessment of breast cancer risk in patients during the development of new MHT or COC is not possible given the requirement of long-term studies in large populations. This translational preclinical research provides new evidence that a therapeutic dose of E4 for MHT or COC, combined with progesterone or drospirenone, may provide a better benefit/risk profile towards breast cancer risk compared to hormonal treatments currently available for patients.