Single-dose pharmacokinetics and pharmacodynamics assessment of oestriol and trimegestone containing vaginal rings in healthy women with childbearing potential.

PURPOSE: To evaluate the pharmacokinetics and pharmacodynamics of oestriol (E3) and trimegestone (TMG) in healthy women after application of three different vaginal rings over 21 days. The vaginal rings had a nominal delivery rate of 0.413/0.050 mg/day (Test 1), 0.311/0.090 mg/day (Test 2) and 0.209/0.137 mg/day (Test 3) E3/TMG. METHODS: Thirty-five healthy women were randomised to receive a single application of Test 1, 2 or 3 (Clinical Trial NCT03343912). The E3 and TMG plasma concentration was determined by LC-MS/MS. Oestradiol (E2) and progesterone (PG) serum concentrations, and bleeding patern were determined as pharmacodynamic parameters. Safety was assessed by evaluation of adverse events and local tolerability. RESULTS: The total and maximum exposure of E3 and TMG increased in a proportional ratio to dose. However, not in a magnitude which was expected from the dose differences for E3. During Test 2 and 3 treatment all E2 and PG values remained on a well suppressed level until end of treatment. E2 and PG serum levels increased distinctly earlier after ring removal with Test 1 compared to Test 2 and 3. Test 3 achieved 95.24% of "no bleeding" days under treatment followed by Test 1 (91.67%), and Test 2 (86.15%). CONCLUSIONS: The Test 3 formulation presented the best dose combination of E3/TMG for contraception. Moreover, all vaginal rings were well tolerated.

Ovulation inhibition with a new vaginal ring containing trimegestone.

OBJECTIVES: The primary objective was to determine the lowest trimegestone (TMG) dose, administered via a vaginal ring, that effectively inhibited ovulation. STUDY DESIGN: Single-centre, open-label, single-dose, parallel-group clinical trial with adaptive design. Eighty healthy female volunteers with proven ovulatory cycles were allocated to treatment with a vaginal ring during 28 days, with an average daily release rate of either 46 µg, 94 µg, 147 µg, or 184 µg TMG (20 women/group). Ultrasound measurements of follicular growth and endometrial thickness, and blood sampling for follicle-stimulating hormone, luteinizing hormone, estradiol and progesterone determinations were performed every 3rd (±1) day from treatment day 4 (±1) until day 28 (±1), and in a follow-up phase after ring removal, until study day 39 (±1). Trimegestone concentrations were measured at each visit in the treatment phase. RESULTS: Mean age and body mass index were 28.8 years and 23.15 kg/m2. One subject in the lowest dose group (46 µg/day) ovulated, no ovulations were seen in the higher dose groups. The degree of ovarian suppression increased with the dose. Median estradiol levels were 119, 36.5, 33.2 and 27.2 pg/mL in the 46, 94, 147 and 184 µg/day groups, respectively. Ovarian activity was resumed in the follow-up phase. Plasma TMG levels gradually declined over the treatment period and showed dose proportionality. The study treatment was safe and well tolerated. CONCLUSION: The release rate of 94 µg TMG per day was the lowest effective dose for ovulation inhibition. The study results justify further development of the TMG-ring as progestogen-only contraceptive. IMPLICATIONS: The vaginal ring releasing TMG seems to be an effective new progestogen-only contraceptive preparation, having the advantage of once-a-month vaginal insertion.

A randomized, controlled pilot trial of hormone therapy for menopausal insomnia.

Insomnia is a frequent climacteric symptom. This pilot, double-blind, randomized placebo-controlled trial compared estradiol associated with trimegestone or placebo in 12 women with perimenopausal insomnia. The Pittsburgh Sleep Quality Index (PSQI) was administered, and polysomnography was performed at baseline and after 28 days. Sleep efficiency and median score of the PSQI improved significantly in the hormone therapy group (HT) (p=0.041 and p=0.027, respectively) and not in placebo group. Perimenopausal insomnia improved after short-term HT.

[Effect of trimegestone on mammary gland of castrated rats]. / Efeito da trimegestona sobre o tecido mamário de ratas castradas.

PURPOSE: To evaluate the efect of trimegestone on the histological changes of the mammary tissue of castrated rats. METHODS: Forty-five virgin female Wistar rats were used after oophorectomy. Sixty days after surgery, with hypoestrogenisms confirmed, the experimental rats were randomly assigned to three groups of 15 animals each, when then the specific treatment for each group was started. The control group (C) and experimental groups 1 and 2 respectively received 0.9% saline solution, 17-beta-estradiol and 17-beta-estradiol in combination with trimegestone for 60 consecutive days. After the end of treatment , the inguinal mammary glands were removed, stained with hematoxylin and eosin (HE) for morphometry and examined by immunohistochemistry for the quantification of anti-PCNA antibody in the mammary tissue, followed by euthanasia. The morphometric parameters evaluated were: epithelium cell-proliferation, secretor activity and mammary stroma changes. There were nine deaths during the experiment. The variables were submitted to statistical analysis adopting the 0.05 level of significance. RESULTS: Histological changes were observed in 16/36 rats, mild epithelial hyperplasia in 13/36, moderate epithelial hyperplasia in 3/36, with no cases of severe epithelial hyperplasia. Stromal fibrosis was found in 10/36 and secretory activity in 5/36 rats. All morphometric variables were significant in the estrogen group compared to control (p=0.0361), although there were no difference between the group receiving combined treatment and the controls (p=0.405). The immunohistochemical analysis showed no difference between groups. CONCLUSIONS: The hormones administered to castrated rats, i.e., 17 beta-estradiol alone or in combination with trimegestone, increased the proliferation of breast cells, but this effect appeared to be lower in the combined treatment, the same occurring regarding fibrosis of the mammary stroma.

Efeito da trimegestona sobre o tecido mamário de ratas castradas / Effect of trimegestone on mammary gland of castrated rats

OBJETIVO: Avaliar o efeito da trimegestona sobre a proliferação celular do tecido mamário de ratas castradas. MÉTODOS: Foram utilizadas 45 ratas adultas e virgens, da linhagem Wistar, submetidas à castração. Após o 60º dia da castração, confirmado o hipoestrogenismo, os animais foram divididos aleatoriamente em três grupos, conforme o tratamento proposto: controle (n=15) recebeu soro fisiológico 0,9 por cento; estrogênio (n=15) recebeu 17 beta-estradiol; e combinado (n=15) recebeu 17 beta-estradiol associado à trimegestona, todos por 60 dias consecutivos. Após o término do tratamento, procedeu-se a exérese das mamas inguinais, destinadas a análise morfométrica pela coloração de hematoxilina e eosina (HE) e imuno-histoquímica pela quantificação do anticorpo anti-PCNA no tecido mamário, seguido de eutanásia. Os parâmetros morfométricos avaliados foram: proliferação celular epitelial, atividade secretora e alteração do estroma mamário. Ocorreram nove óbitos durante o experimento. As variáveis foram submetidas à análise estatística adotando-se como significante p<0,05. RESULTADOS: Foram observadas alterações histológicas em 16/36 ratas, hiperplasia epitelial leve em 13/36, hiperplasia epitelial moderada em 3/36, não sendo encontrada hiperplasia epitelial severa. Encontrou-se fibrose no estroma em 10/36 e atividade secretora em 5/36 das ratas. Todas as variáveis do estudo morfométrico foram significantes comparando-se os grupos controle e estrogênio (p=0,03), e nenhuma foi significante na comparação dos grupos controle e combinado (p=0,4). A análise imuno-histoquímica não mostrou diferença entre os grupos. CONCLUSÃO: Os hormônios usados em ratas castradas aumentaram a proliferação de células mamárias, tanto o 17 beta-estradiol isolado quanto associado à trimegestona, porém este efeito parece ser menor quando se emprega a associação, o mesmo ocorrendo em relação à fibrose do estroma mamário.

PURPOSE: To evaluate the efect of trimegestone on the histological changes of the mammary tissue of castrated rats. METHODS: Forty-five virgin female Wistar rats were used after oophorectomy. Sixty days after surgery, with hypoestrogenisms confirmed, the experimental rats were randomly assigned to three groups of 15 animals each, when then the specific treatment for each group was started. The control group (C) and experimental groups 1 and 2 respectively received 0.9 percent saline solution, 17-beta-estradiol and 17-beta-estradiol in combination with trimegestone for 60 consecutive days. After the end of treatment , the inguinal mammary glands were removed, stained with hematoxylin and eosin (HE) for morphometry and examined by immunohistochemistry for the quantification of anti-PCNA antibody in the mammary tissue, followed by euthanasia. The morphometric parameters evaluated were: epithelium cell-proliferation, secretor activity and mammary stroma changes. There were nine deaths during the experiment. The variables were submitted to statistical analysis adopting the 0.05 level of significance. RESULTS:Histological changes were observed in 16/36 rats, mild epithelial hyperplasia in 13/36, moderate epithelial hyperplasia in 3/36, with no cases of severe epithelial hyperplasia. Stromal fibrosis was found in 10/36 and secretory activity in 5/36 rats. All morphometric variables were significant in the estrogen group compared to control (p=0.0361), although there were no difference between the group receiving combined treatment and the controls (p=0.405). The immunohistochemical analysis showed no difference between groups. CONCLUSIONS:The hormones administered to castrated rats, i.e., 17 beta-estradiol alone or in combination with trimegestone, increased the proliferation of breast cells, but this effect appeared to be lower in the combined treatment, the same occurring regarding fibrosis of the mammary stroma.

Cardiovascular risk markers during treatment with estradiol and trimegestone or dydrogesterone.

OBJECTIVE: To study cardiovascular risk markers in women taking estradiol/trimegestone or estradiol/dydrogesterone. DESIGN: Multicenter, randomized, prospective, double-blind study of 184 healthy post-menopausal women randomized to 6 cycles of either estradiol (2mg)+trimegestone (0.5mg) (T-group) or estradiol (2mg)+dydrogesterone (10mg) (DYDR group). Cardiovascular risk markers were measured before, after cycle 1, 3 and 6 and at 4 weeks post-treatment. RESULTS: Fibrinogen was reduced in both groups but more markedly in the DYDR group. Factor VIIc activity levels decreased in both groups with a greater change in the T-group. Factor VII antigen was increased in both groups with a greater increase in the DYDR group. Factor VIIa was increased in the DYDR group only. Plasminogen levels were also increased in both groups with a greater increase in the T-group. There were no statistically significant changes in lipid variables between the different regimens. Changes in total cholesterol and LDL cholesterol were correlated positively with changes in factor VIIc in the DYDR group and negatively with changes in factor VIIc in the T-group. Trigemestone was associated with a better bleeding pattern. CONCLUSIONS: Trimegestone was associated with less procoagulant changes in factor VIIa and factor VIIc activity and larger decrease in PAI-1 activity compared with the dydrogesterone preparation. These results reflect less androgenic properties of the trimegestone preparation. The fibrinogen level and Lp(a) were more decreased during dydrogesterone treatment. Further investigation is required to clarify the relative importance of beneficial effects with respect to cardiovascular risk.

Inhibitors and activation markers of the haemostatic system during hormone therapy: a comparative study of oral estradiol (2 mg)/ dydrogesterone and estradiol (2 mg)/ trimegestone.

Epidemiological studies have shown that hormone therapy (HT) increases the risk of venous thromboembolism in post menopausal women. The mechanism of this increased risk is unknown; however, activation of the haemostatic system is known to contribute to the pathogenesis of venous thromboembolism. In post-menopausal women the estrogen/progestogen composition of the HT can influence the level of haemostatic activation. It was the objective of this study to compare changes in inhibitors and activation markers of the haemostatic system in healthy post-menopausal women taking estradiol (2 mg) combined with dydrogesterone or a new progestin, trimegestone. A multicentre study of 186 women randomised to six months therapy with either estradiol (2 mg) +trimegestone (0.5 mg) or estradiol (2 mg) +dydrogesterone (10 mg) was performed. Antithrombin and protein S activity was decreased and activated protein C (APC) resistance, D-dimer and prothrombin fragment 1.2, were increased in both groups on treatment. Protein C activity was decreased and plasmin-antiplasmin complex was increased in the trimegestone group only. The increase in plasmin-antiplasmin complex and D-dimer was greater after six cycles of treatment in the trimegestone group compared with the dydrogesterone group. In conclusion, decreased levels of inhibitors of blood coagulation and increased thrombin production were found in both groups however a greater increase in the levels of plasmin-antiplasmin complex and D-dimer was found in the trimegestone group. This suggests an enhanced fibrinolytic response in this group. Further studies are required to determine the significance of this finding with respect to venous thrombosis risk.

Parallel assessment of the impact of different hormone replacement therapies on breast density by radiologist- and computer-based analyses of mammograms.

OBJECTIVES: First, to compare the impact of nasally and orally dosed estradiol on breast density; second, to investigate the utility of computer-based automated approaches to the assessment of breast density with reference to traditional methods. METHODS: Digitized images from two 2-year, randomized, placebo-controlled trials formed the basis of the present post hoc analysis. Active treatments were 1 mg estradiol continuously combined with 0.125 mg trimegestone (oral hormone replacement therapy, HRT) or low-dose (150 or 300 microg estradiol) nasal estradiol cyclically combined with 200 mg micronized progesterone (nasal HRT). The effects on breast density were assessed by a radiologist, providing the BI-RADS score and the interactive threshold, and by a computer-based approach, providing the measure of stripiness and the HRT-effect specific measure of breast density. RESULTS: In the oral HRT trial, active treatment induced a significant increase in breast density, which was consistent in all methods used (all p < 0.05). In contrast, none of the methods detected significant changes in women receiving nasal HRT. The sensitivity of automated methods to discriminate HRT- from placebo-treated women was equal or better than the sensitivity of methods performed by the radiologist. CONCLUSIONS: The markedly different pharmacokinetic profile of nasal estrogen seems to be associated with better breast safety. Automated computer-based analysis of digitized mammograms provides a sensitive measure of changes in breast density induced by hormones and could serve as a useful tool in future clinical trials.

Preclinical and clinical properties of trimegestone: a potent and selective progestin.

Trimegestone (TMG) is a novel, 19-norpregnane progestin with potent and selective properties. In preclinical studies, TMG has been shown to provide high endometrial selectivity. Further, TMG has high affinity and selectivity for the progesterone receptor and lacks the agonist effects of other steroid hormones. In clinical studies, TMG has been shown to have high endometrial safety and an improved bleeding profile along with improved tolerability compared with other progestins. In addition, TMG also does not impede the beneficial effects of estrogen, especially on bone, and does not compromise quality of life. The preclinical findings of lack of mineralocorticoid activity of TMG were supported in clinical findings, with neutral effect on body weight. Similarly, the smaller effect of TMG on the GABA-ergic (gamma-aminobutyric acid) system in preclinical studies is consistent with the improvement of central nervous system-related effects on depressed mood and sleep quality in clinical studies. Low-dose estradiol/TMG regimens provide rapid relief from menopausal symptoms, reducing the number and severity of hot flushes as effectively as 2 mg 17beta-estradiol/1 mg norethisterone acetate. Therefore, it may be concluded that TMG provides a clinically proven option in hormone therapy for both clinicians and patients.

Trimegestone differentially modulates the expression of matrix metalloproteinases in the endometrial stromal cell.

Matrix metalloproteinases (MMP) are considered to be of critical importance in the initiation of menstruation where MMP protein levels are reciprocally modulated by the actions of the gonadal steroid hormones, estradiol (E(2)) and progesterone (P4), with P4 being considered the principal suppressor of endometrial MMP expression. Trimegestone (T) is a novel progestagen that tightly controls menstruation timing and duration through mechanisms that might involve MMP suppression. Endometrial stromal cells treated with 10(-6) M E(2), P4 or T in the presence and absence of 10(-6)M RU486 showed that both T and P4 suppressed the expression of MMP-1 and MMP-3 transcripts and secreted protein, whereas MMP-9 was not produced in culture. The suppressive effect of T or P4 on MMP-1 and MMP-3 transcript levels was enhanced in the presence of E(2) and attenuated in the presence of RU486, although MMP-1 proteins were unaffected by the presence of RU486, which alone acted as a partial progesterone agonist in these cultures. Immunohistochemistry with MMP-1, MMP-3 and MMP-9-specific antibodies performed on endometrial biopsies obtained from non-treated, LH-dated, normally cycling women and endometrial biopsies obtained from postmenopausal women treated with T-based HRT showed that immunoreactive MMP-1 and MMP-3 was higher in the menstrual phase, whilst MMP-9 expression was higher in the late luteal phase (P = 0.03) and T significantly inhibited the presence of MMP-9(+) cells. These data suggest that T acts in a similar manner to P4, but causes subtle differences in expression patterns of MMPs that may explain the different clinical effect that this progestagen has on endometrial behaviour compared to P4.

New progestagens for contraceptive use.

The progestins have different pharmacologic properties depending upon the parent molecule, usually testosterone or progesterone (P), from which they are derived. Very small structural changes in the parent molecule may induce considerable differences in the activity of the derivative. In hormonal contraceptives, progestins represent the major agent designed for suppressing ovulation and are used in combination with estrogen (E) usually ethinyl-estradiol (EE). The development of new generations of progestins with improved selectivity profiles has been a great challenge. Steroidal and nonsteroidal progesterone receptor (PR) agonists have been synthesized as well, although the latter are still in a very early stage of development. Several new progestins, have been synthesized in the last two decades. These include dienogest (DNG), drospirenone (DRSP), Nestorone (NES), nomegestrol acetate (NOMAc) and trimegestone (TMG). These new progestins have been designed to have no androgenic or estrogenic actions and to be closer in activity to the physiological hormone P. DRSP differs from the classic progestins as it is derived from spirolactone. It is essentially an antimineralocorticoid steroid with no androgenic effect but a partial antiandrogenic effect. The antiovulatory potency of the different progestins varies. TMG and NES are the most potent progestins synthesized to date, followed by two of the older progestins, keto-desogestrel (keto-DSG) and levonorgestrel (LNG). The new molecules TMG, DRSP and DNG also have antiandrogenic activity. Striking differences exist regarding the side effects among the progestins and the combination with EE leads to other reactions related to the E itself and whether the associated progestin counterbalances, more or less, the estrogenic action. The 19-norprogesterone molecules and the new molecules DRSP and DNG are not androgenic and, therefore, have no negative effect on the lipid profile. Given their pharmacological properties, it is likely that the new progestins may have neutral effects on metabolic or vascular risks. However, this hypothesis must be confirmed in large clinical trials.

Bleeding profile and endometrial safety of continuous combined regimens 1 mg 17beta-estradiol/trimegestone versus 1 or 2 mg 17beta-estradiol/norethisterone acetate in postmenopausal women.

OBJECTIVE: To compare the bleeding profile and endometrial safety of continuous combined 1 mg 17beta-estradiol (17beta-E2) and 0.125 mg trimegestone (TMG) with those of two continuous combined 17beta-E2 and norethisterone acetate (NETA) regimens. STUDY DESIGN: This was a double-blind, randomized, multicenter study conducted in 12 European countries and Israel over a 2-year period. Healthy postmenopausal women with an intact uterus were given either 1 mg 17beta-E2/0.125 mg TMG, 2 mg 17beta-E2/1 mg NETA or 1 mg 17beta-E2/0.5 mg NETA for up to 26 cycles, each of 28 days. RESULTS: The percentage of amenorrheic women was greater in most cycles up to cycle 13 in the 1 mg 17beta-E2/0.125 mg TMG group than in the comparator groups. The mean number of bleeding days was similar in the 1 mg 17beta-E2/0.125 mg TMG and the 1 mg 17beta-E2/0.5 mg NETA groups, but greater in the 2 mg 17beta-E2/1 mg NETA group. No endometrial hyperplasia was observed for any group. CONCLUSION: Continuous combined 1 mg 17beta-E2/0.125 mg TMG exhibits a more favorable bleeding profile than 1 mg 17beta-E2/0.5 mg NETA up to 1 year, while providing an adequate protective effect on the endometrium.

Efficacy on climacteric symptoms of a continuous combined regimen of 1 mg 17beta-estradiol and trimegestone versus two regimens combining 1 or 2 mg 17beta-estradiol and norethisterone acetate.

OBJECTIVES: To compare the efficacy of a continuous combined regimen of 1mg 17beta-estradiol (17beta-E2) and 0.125 mg trimegestone (TMG) with two continuous combined 17beta-E2/norethisterone acetate (NETA) combinations in the relief of climacteric symptoms in postmenopausal women. STUDY DESIGN: This was a randomized, double-blind, multicenter study conducted in 13 countries over a 2-year period. Healthy postmenopausal women with an intact uterus were treated with 1 mg 17beta-E2/0.125 mg TMG, 2 mg 17beta-E2/1 mg NETA or 1 mg 17beta-E2/0.5 mg NETA for up to 26 cycles, each of 28 days. RESULTS: The 1 mg 17beta-E2/0.125 mg TMG combination was effective in significantly reducing the mean daily number and severity of hot flushes and in reducing the number of night sweats from cycle 1 onward. No overall significant differences between this regimen and the comparators were detected. Other efficacy variables, including the Kupperman index, psychofunctional disorders and quality-of-life sub-scales, experienced a similar improvement from baseline with all treatments. CONCLUSION: Continuous combined 1 mg 17beta-E2/0.125 mg TMG provides relief of menopausal symptoms that is non-inferior to both 17beta-E2/NETA combinations. Furthermore, trimegestone appeared to provide a better improvement of depressive mood than 0.5 mg NETA when combined with 1 mg 17beta-estradiol.

A study of the control of climacteric symptoms in postmenopausal women following sequential regimens of 1 mg 17beta-estradiol and trimegestone compared with a regimen containing 1 mg estradiol valerate and norethisterone over a two-year period.

OBJECTIVE: To compare the efficacy of two sequential 17beta-estradiol (17beta-E2)/trimegestone (TMG) combinations with the sequential estradiol valerate (E2V)/norethisterone (NET) regimen in relieving climacteric symptoms. STUDY DESIGN: This was a double-blind, randomized, multicenter study conducted among 1218 Caucasian (99%) postmenopausal women with an intact uterus in seven European countries and Israel, over 13 cycles (each of 28 days). Study duration was extended further for 13 cycles, with 531 women receiving treatment for up to 26 cycles. Treatments consisted of 1 mg 17beta-E2 on days 1-14 and 1 mg 17beta-E2/0.125 mg TMG or 0.25 mg TMG on days 15-28, and 1 mg E2V on days 1-16 and 1 mg E2V/1 mg NET on days 17-28. RESULTS: Rapid and significant reductions in the mean daily number and severity of hot flushes and in the mean daily number of nocturnal sweats were established in most women with 1 mg 17beta-E2/0.25 mg TMG and E2V/NET. These treatments also induced a significant improvement in the quality-of-life assessments. CONCLUSION: The 1 mg 17beta-E2/0.25 mg TMG regimen provides rapid and effective relief of menopausal symptoms, with a reduction in the number of hot flushes "at least as good as" that of the E2V/NET comparator.

A comparative 2-year study of the effects of sequential regimens of 1 mg 17beta-estradiol and trimegestone with a regimen containing estradiol valerate and norethisterone on the bleeding profile and endometrial safety in postmenopausal women.

OBJECTIVE: To compare the bleeding profiles and endometrial protection of two sequential regimens of 17beta-estradiol (17beta-E2) and trimegestone (TMG) with a sequential estradiol valerate (E2V)/norethisterone (NET) regimen. STUDY DESIGN: This was a randomized, double-blind, multicenter study conducted in eight countries in healthy, postmenopausal women with an intact uterus. A total of 1218 women were enrolled into the initial 1-year study (13 cycles), and subsequently 531 of these received treatment for a further year (26 cycles). Treatment regimens were 1 mg 17beta-E2 on days 1-14 and 1 mg 17beta-E2/0.125 mg TMG or 1 mg 17beta-E2/0.25 mg TMG on days 15-28, and 1 mg E2V on days 1-16 and 1 mg E2V/1 mg NET on days 17-28. RESULTS: Mean percentage of women reporting onset of withdrawal bleeding episodes during the week following discontinuation of progestogen was higher in the 1 mg 17beta-E2/0.25 mg TMG group than in the other two treatments, showing a more efficient progestogen effect on the endometrium and good predictability of bleeding onset with this treatment. The mean numbers and average lengths of bleeding episodes were similar in the three treatment groups. Overall, the bleeding profile was more favorable with 1 mg 17beta-E2/0.25 mg TMG than with the lower-dose TMG preparation. Both of the TMG regimens demonstrated a good protective effect on endometrial proliferation, with the 0.25 mg TMG dose showing a lower incidence of proliferative endometrium. CONCLUSION: The 1 mg 17beta-E2/0.25 mg TMG regimen showed an adequate protection of the endometrium, with an overall favorable bleeding profile.

Quantitative analysis of gene regulation by seven clinically relevant progestins suggests a highly similar mechanism of action through progesterone receptors in T47D breast cancer cells.

Progesterone (P4) is an essential reproductive steroid hormone required for many aspects of female reproductive physiology. Progestins are compounds that demonstrate progesterone-like activity and are used in oral contraception, hormone therapy, and treatment of some reproductive disorders, but differ widely in their chemical structures, potency, and pharmacokinetics. While numerous studies have assessed progestins on specific endpoints, little is known about the activation of global gene expression by progestins. We used Affymetrix GeneChip U133A expression arrays to examine the action of P4 and six clinically relevant synthetic progestins (3-ketodesogestrel, drospirenone, levonorgestrel, medroxyprogesterone acetate, norethindrone acetate, and trimegestone) on the progesterone receptor (PR)-positive T47Dco and the PR-negative T47D-Y breast cancer cell lines. Excluding drospirenone, one or more of the progestins-regulated 329 genes, with 30 genes regulated by at least 2.0-fold by all progestins in the T47Dco cells. The synthetic progestins show a high degree of similarity in their transcriptional responses, and each progestin regulates between 77 and 91% of the genes regulated by P4. Independent quantitative RT-PCR analysis confirmed a similar regulation for S100P, PPL, IL20RA, NET1, ATP1A1, HIG2, and CXCL12 (SDF-1) by all seven progestins. Attempts to find differentially regulated genes by any progestin compared to all other treatments failed, suggesting any differences are quantitative, not qualitative. This analysis demonstrates a high degree of similarity among these progestins on PR-regulated gene expression in T47D cells, suggesting a similar and fairly specific mode of action.

Molecular and pharmacological properties of a potent and selective novel nonsteroidal progesterone receptor agonist tanaproget.

Progesterone receptor (PR) agonists have several important applications in women's health, such as in oral contraception and post-menopausal hormone therapy. Currently, all PR agonists used clinically are steroids. Because of their interactions with other steroid receptors, steroid-metabolizing enzymes, or other steroid-signaling pathways, these drugs can pose significant side effects in some women. Efforts to discover novel nonsteroidal PR agonists with improved biological properties led to the discovery of tanaproget (TNPR). TNPR binds to the PR from various species with a higher relative affinity than reference steroidal progestins. In T47D cells, TNPR induces alkaline phosphatase activity with an EC(50) value of 0.1 nm, comparable with potent steroidal progestins such as medroxyprogesterone acetate (MPA) and trimegestone (TMG), albeit with a reduced efficacy ( approximately 60%). In a mammalian two-hybrid assay to measure PR agonist-induced interaction between steroid receptor co-activator-1 and PR, TNPR showed similar potency (EC(50) value of 0.02 nm) and efficacy to MPA and TMG. Importantly, in key animal models such as the rat ovulation inhibition assay, TNPR demonstrates full efficacy and an enhanced progestational potency (30-fold) when compared with MPA and TMG. Furthermore, TNPR has relatively weak interactions with other steroid receptors and binding proteins and little effect on cytochrome P450 metabolic pathways. Finally, the three-dimensional crystal structure of the PR ligand binding domain with TNPR has been delineated to demonstrate how this nonsteroidal ligand achieves its high binding affinity. Therefore, TNPR is a structurally novel and very selective PR agonist with an improved preclinical pharmacological profile.

Differential effects of estrogens and progestins on the anticoagulant tissue factor pathway inhibitor in the rat.

Oral contraceptives (OC) and postmenopausal hormone therapy (HT) modulate plasma levels of proteins that regulate blood coagulation. It remains unclear whether the progestin component contributes to these changes. The present study was designed to determine whether progestins modulate two essential plasma anticoagulants, antithrombin (AT) and tissue factor pathway inhibitor (TFPI), in an animal model. Ovariectomized rats were treated orally with three progestins, norethindrone acetate (NETA), trimegestone (TMG), or drospirenone (DSP), either alone or combined with 17alpha-ethyinylestradiol (EE). Plasma AT levels were unchanged. However, TFPI activity was reduced by EE alone (10-100 microg/kg/day) in a dose-dependent manner; NETA (3 or 10 mg/kg/day) reduced TFPI by approximately 40 or approximately 80%, respectively, while TMG and DSP had no effect. NETA and EE effects were blocked by co-administration of ICI-182,780, an estrogen receptor antagonist, suggesting that both responses were likely estrogen receptor-mediated. Reduced TFPI after NETA or EE treatment was not accompanied by changes in TFPI mRNA levels in tissues that express TFPI, but there was a positive correlation between plasma TFPI and total cholesterol. Sex hormone effects on TFPI in this model and as reported in women may help to shift the coagulation balance to a more prothrombotic state. Progestins such as TMG and DSP that lack estrogenic activity could potentially have an improved clinical profile.

Sleep apnea and hormone replacement therapy: a pilot study and a literature review.

BACKGROUND: Sleep apnea syndrome (SAS) is a common condition and a risk factor of cardiovascular and cerebrovascular diseases. The purpose of this pilot study was to investigate the effect of a gestagen (trimegeston) and estradiol hormone combination on perimenopausal and postmenopausal women with SAS. METHODS: Four postmenopausal and one perimenopausal women were studied by polysomnography before and after treatment with hormone replacement therapy (HRT). RESULTS: The subjects had a mean reduction of the severity of their sleep apnea by 75% measured by apnea/hypopnea index. CONCLUSIONS: HRT might be an alternative in the treatment of SAS.

Trimegestone in a low-dose, continuous-combined hormone therapy regimen prevents bone loss in osteopenic postmenopausal women.

OBJECTIVE: To determine the efficacy of estrogen + progestogen therapy with 1 mg 17beta-estradiol and 0.125 mg trimegestone in the prevention of postmenopausal osteoporosis. DESIGN: For this study, 360 healthy, postmenopausal women with osteopenia [lumbar spine bone mineral density (BMD) between -1.0 and -2.5 SD of the premenopausal mean value] were enrolled in a 2-year prospective, randomized study, and 70% completed. Treatments were 1 mg 17beta-estradiol + 0.125 mg trimegestone (n = 179) or placebo (n = 181), given as daily oral therapy. All received a daily supplement of 500 mg calcium and 400 IU vitamin D. BMD measurements at the lumbar spine, total hip, and femoral neck as well as blood and urinary biochemical markers of bone turnover (serum osteocalcin), serum bone-specific alkaline phosphatase, serum CrossLaps, and urinary CrossLaps took place regularly. RESULTS: BMD increases relative to placebo were 6.3%, 3.9%, and 3.8% at the lumbar spine, total hip, and femoral neck, respectively (all P < 0.001). The biochemical markers of bone turnover were suppressed accordingly. Serum CrossLaps and urinary CrossLaps decreased rapidly, by 52% and 54%, respectively, whereas serum osteocalcin and serum bone-specific alkaline phosphatase revealed a more retarded decrease of 40% and 33%, respectively. Of the women receiving hormone therapy, 75% had amenorrhea from the first cycle, and 5% withdrew prematurely due to metrorrhagia or mastalgia. CONCLUSION: This new estrogen + progestogen therapy is efficient in increasing BMD in an osteopenic postmenopausal population. Furthermore, it is well tolerated, with few adverse events and an early bleeding control, which is likely to improve compliance to the treatment over the long term.