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To determine the incidence of out-of-range segesterone acetate (NES) concentrations in participants of a pharmacokinetic/pharmacodynamic trial of a continuous use contraceptive vaginal ring (CVR) releasing NES and estradiol (E2). We hypothesized that out-of-range concentrations reflect nonadherent ring use and predict ovulation risk.We conducted a secondary analysis of data from a prospective, multi-centered, randomized, Phase IIa dose-finding trial for a CVR releasing NES and E2. Our primary outcome was the risk of ovulation associated with out-of-range NES events. We calculated the 5th and 95th percentile NES concentrations of subjects at steady state to determine high and low cutoffs. We used a Fisher's exact test to determine group differences, and calculated the relative risk of ovulation for each group.We analyzed available serum NES data from cycles 2 (n = 172), 3 (n = 156) and 7 (n = 115) to determine the 5th and 95th percentile of all NES concentrations (64, 296 pg/mL). In the 443 cycles of observation, no ovulations occurred in participants with NES concentrations within the expected range. In contrast, we found ovulatory elevations of progesterone in 21 cycles with out-of-range values. Of these, 15 (71%) cycles had evidence of one or more nonadherent low and 6 (29%) one or more unexpected peak. The relative risk of ovulation increased with evidence of multiple non-adherent levels.We found out-of-range NES concentrations, suggestive of improper use of a CVR associated with an increased risk of ovulation, with a direct relationship between the number of out-of-range events and the relative risk.The results of this study support the use of out-of-range serum NES values as a marker of adherence in contraceptive clinical trials of continuous vaginal rings, and suggest that nonadherence occurs even in early phase clinical trials with close monitoring.

Ischemic stroke remains a significant unmet need causing massive mortality and morbidity due to few treatment options with limited therapeutic window. The progestin Nestorone® (segesterone acetate) displays high affinity for the progesterone receptor in exerting its potent birth control and hormone replacement therapy. Accumulating evidence implicates a new utility of Nestorone in affording neuroprotection in a variety of central nervous system diseases, including stroke. However, the mechanism of action mediating Nestorone's neuroprotection in stroke remains unknown. Here, we showed that stand-alone treatments of Nestorone or human amniotic fluid-derived stem cells (hAFSc), but more pronounced with their combined treatment, led to significant improvements in behavioral function and reductions in infarction and peri-infarct cell loss in adult rats with ischemic stroke. We detected significantly lower levels of pro-inflammatory signals (OX6 and IBA1) coupled with enhanced levels of stem cell proliferation (Ki67) and differentiation (DCX and MAP2) in both brain and spleen of stroke rats that received stand-alone or combined treatments of Nestorone and hAFSc. In concert, the in vitro oxygen-glucose deprivation stroke model revealed that neural stem cells treated with Nestorone exhibited increased stem cell proliferation and differentiation that was accompanied by rescue of the mitochondrial respiratory activity characterized by reduced mitochondrial reactive oxygen species, increased ATP, elevated mitochondrial deacetylase Sirtuin 3 (SIRT3), and a normalized ratio of acetyl-superoxide dismutase 2 (Ac-SOD2)/SOD2, suggesting the key role of mitochondrial metabolism and oxidative protection in Nestorone's therapeutic effects in stroke.

Introduction We previously showed that Nestorone® (NES), a synthetic progestin structurally related to progesterone, stimulated remyelination of the corpus callosum in a Cuprizone (CUP) mouse model of demyelination in intact females by promoting replenishment with mature oligodendrocytes (OL) (Glia. 2015;63:104‐117). Here, we further investigated the underlying mechanisms of this promyelinating effect. Methods We explored whether NES, applied subcutaneously through Alzet mini‐osmotic pumps, regulates specific transcription factors involved in oligodendrocyte progenitor cell (OPC) proliferation and their differentiation into mature OL, using RT‐qPCR and Western Blot analysis. Results Our present data show that in comparison to controls, a one‐week treatment with NES, through Alzet mini‐osmotic pumps, enhanced the production of three relevant transcription factor mRNAs encoding Olig2, Myt1, and Sox17. After 3 weeks, NES treatment reversed the effect of CUP on the levels of corresponding Olig2, Myt1, and Sox17 proteins. Moreover, in mice receiving NES + Estradiol (E2) co‐treatment, levels of Olig2, Myt1, and Sox17 proteins did not change as compared to NES alone. Conclusion NES alone or with E2 increased the levels of transcription factors, essential for myelin synthesis., Schematic view of the first demonstration of the mechanism by which Nestorone® a synthetic progestin structurally related to progesterone stimulates remyelination of the corpus callosum in a mouse model of demyelination, by increasing the levels of transcription factors Olig2, Myt1, and Sox17 proteins, essential for myelin synthesis after one week of treatment.

Objective To develop a method to simultaneously quantify the synthetic contraceptive progestin segesterone acetate (Nestorone®, NES) and the endogenous steroid hormones estradiol (E2), progesterone (P4), and estrone (E1) in human serum samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Study Design We analyzed 615 serum samples collected from 67 reproductive-age women actively using a contraceptive vaginal ring (CVR) designed to release NES (200 mcg/d) and E2 (75-200 mcg/d). Samples were taken prior to and up to 30 days after CVR insertion and analyzed for concentrations of NES, E2, P4, and E1 in human serum using a Shimadzu Nexera-LCMS-8050 LC-MS/MS platform. Precision, accuracy, and sensitivity for all analytes were determined across multiple assays. Results The assay ranges for NES, E2, P4, and E1 in this analytical method were 10 pg/mL to 10 ng/mL with a lower limit of quantification of 10 pg/mL for all targets. Assay precisions were less than or equal to 14.5% and accuracies ranged from 87.0% – 110.8%. When applied to the 615 clinical samples, 550 samples had quantifiable concentrations of NES (value range 0.014 ng/mL – 1471 ng/mL). Similarly, 595 samples had quantifiable concentrations of E2 (0.010 ng/mL – 0.312 ng/mL), 596 samples had quantifiable concentrations of P4 (0.010 ng/mL – 5.791 ng/mL), and 609 samples had quantifiable concentrations of E1 (0.010 ng/mL – 0.416 ng/mL). Conclusions The LC-MS/MS platform results in a robust, accurate, and sensitive method for the simultaneous quantification of NES and endogenous steroid hormones in human serum. Implications The analytical method described allows for the simultaneous quantification of NES and endogenous steroids and can be used to monitor NES concentrations during clinical trials and subject adherence to treatment with NES.

Objective Progesterone is a potent neuromodulator that exerts effects on the brain through neurosteroids, progesterone receptors (PRs), and other molecules. Whether PR activation regulates seizures is not known. We determined whether PR activation increased seizure susceptibility. Methods Adult female rats that developed epilepsy following lithium‐pilocarpine‐induced status epilepticus (SE) were used. Seizures were recorded by continuous‐video EEG and read by an individual blinded to the treatment of the animals. The animals were treated for a week with progesterone (50 mg/kg per day), and the effect of progesterone withdrawal on seizure frequency was assessed during the subsequent week. During the week of progesterone treatment, the animals were treated with PR antagonist RU‐486 (10 mg/kg per day) or a vehicle control, which was administered 30 min before progesterone. In another set of animals, we determined the effect of the PR agonist Nestorone (3 mg/kg per day) on seizure frequency. The animals were treated with Nestorone or vehicle for a week, and seizure frequencies at baseline and during the treatment week were compared. Results Progesterone withdrawal induced twofold increase in seizures in 57% of animals (n = 14). RU‐486 treatment in combination with progesterone, prevented this increase, and a smaller fraction of animals (17%) experienced withdrawal seizures (n = 13). The specific activation of PRs by Nestorone also increased the seizure frequency. Forty‐six percent (n = 14) of Nestorone‐treated animals experienced at least a 50% increase in seizures compared to only 9% of the vehicle‐treated animals (n = 11). Interpretation PR activation increased seizure frequency in epileptic animals. Thus, PRs may be novel targets for treating catamenial epilepsy.

BACKGROUND: Novel male-based contraceptives are needed to broaden family planning choices. A progestin, Nestorone® (Nes) gel, plus a testosterone (T) gel suppresses sperm concentrations to levels associated with effective contraception in normal men. However, administration of two gels on different parts of the body daily is impractical. OBJECTIVE: Compare the effectiveness of daily application of a single, combined 8.3 mg Nes-62.5 mg T gel (Nes-T) vs. 62.7 mg T gel to suppress serum FSH and LH concentrations to ≤ 1.0 IU/L (a threshold associated with suppression of sperm concentrations to ≤ 1 million and effective contraception) and to compare the pharmacokinetics of serum Nes and T concentrations between the gel groups. DESIGN: We conducted a 28-day, double-blind, controlled trial of 44 healthy men randomized to daily Nes-T or T gel with measurement of hormones at baseline, treatment and recovery and during 24-hour pharmacokinetic studies on days 1 and 28 of treatment. RESULTS: Of the subjects who met pre-defined inclusion criteria, 84% of the Nes-T group suppressed serum gonadotropin concentrations to ≤ 1.0 IU/L at days 21–28 vs. 16.7% in the T group (p < .001). On day 1, Nes concentrations rose significantly above baseline by two hours and continued to rise up to 24 hours after Nes-T gel application. Nes concentrations were not detectable in the T group. Serum total T concentrations rose and were significantly higher in the T gel group compared to the Nes-T group at 24 hours on day 1 and days 11, 14, and 21 (p < 0.01). There were no serious adverse events in either group. About 80% of the subjects reported satisfaction with both gels. CONCLUSION: Daily Nes-T gel effectively and safely suppresses serum gonadotropins and is acceptable to most men. It should be studied further in efficacy trials of hormonal male contraception.

"On demand" hormonal female-controlled pericoital contraception is one strategy which could be used to minimize the impact of unintended pregnancy. Nestorone (NES) is a potent contraceptive, with relatively few side effects in comparison with other contraceptives. NES presents an attractive option for "on demand" pericoital contraceptive. Unfortunately, the drug is inactive if taken orally, but it has high progestational activity and antiovulatory potency if administered parenterally. Current drug delivery systems, such as a transdermal hydrogel are not so satisfactory. Dissolving microneedles array (DMNs) are an attractive alternative, minimally-invasive, delivery system. In this study, we report, for the first time, development of tip-loaded NES-nanosuspension (NES-NS)-loaded bilayer DMNs to deliver NES intradermally for subsequent release. NES-NS was prepared and optimised, freeze-dried and then used to fabricate DMNs using a blend of two biocompatible polymers, namely poly(vinyl alcohol) and poly(vinyl pyrrolidone). Both NES-NS and the NES-NS-loaded DMNs were fully characterised and the performance of the DMNs was evaluated in vivo using Sprague Dawley rats. Results showed that the finalised NES-NS had particle size and PDI values of 666.06 ± 1.86 nm and 0.183 ± 0.01, respectively. The NES-NS-DMNs had relatively high tips-localised drug loading (approximately 2.26 ± 1.98 mg/array) and exhibited satisfactory mechanical and insertion properties. In Sprague Dawley rats, DMNs delivered NES into the skin, with the drug then appearing in blood and rapidly reaching its maximum concentration (C

Objective Neurogenesis is the principal regenerative mechanism to sustain the plasticity potential in adult brains. Decreased neurogenesis parallels the cognition decline with aging, and has been suggested as a common hallmark in the progression of many neurodegeneration diseases. We previously reported that acute exposure to segesterone acetate (ST-1435; Nestorone), alone or in combination with 17β-estradiol (E2), increased human neural stem cells proliferation and survival both in vitro and in vivo. The present study expanded our previous findings to investigate the more clinical related chronic exposure in combination with E2 on the regenerative capacity of adult brain. Methods To mimic the chronic contraception exposure in women, 3-month old female mice (n = 110) were treated with ST-1435, with or without co-administration of E2, for 4 weeks. Neural cell proliferation and survival, and oligodendrocyte generation were assessed. The involvement of insulin-like growth factor 1 signaling was studied. Results Our results demonstrated that chronic ST-1435 and E2 alone or in combination increased neurogenesis by a comparable magnitude, with minimum to no antagonistic or additive effects between ST-1435 and E2. In addition, chronic exposure of ST-1435 or ST-1435 + E2 stimulated oligodendrocyte generation, indicating potential elevated myelination. Insulin-like growth factor-1 (IGF-1) and IGF-1 receptor (IGF-1R) were also up-regulated after chronic ST-1435 and E2 exposure, suggesting the involvement of IGF-1 signaling as the potential underlined regulatory pathway transducing ST-1435 effect. Conclusion These findings provide preclinical evidence and mechanistic insights for the development of ST-1435 as a neuroregenerative therapy to promote intrinsic regenerative capacity in female brains against aging and neurodegenerative disorders.

Objectives We sought to identify factors associated with nonadherence to instructions for using a novel contraceptive providing 1 year of protection. Study design Data from a multicountry Phase 3 trial of the Nestorone® (segesterone acetate)/ethinyl estradiol (NES/EE) contraceptive vaginal ring (CVR) were analyzed. Participants were instructed to use the CVR over 13 cycles and follow a 21/7 regimen. Their reports of CVR removals >2 h outside scheduled removal periods served as a proxy for nonadherence. We used multivariate logistic regression to determine factors associated with such use. Results Of 905 participants, 120 (13%) reported CVR removals >2 h. Removals for washing [odds ratio (OR) 3.96, 95% confidence interval (CI) 2.50–6.27] or sexual intercourse (OR 3.19, 95% CI 2.03–4.99), and finding CVR insertion difficult (OR 2.80, 95% CI 1.36–5.80) were factors associated with removals >2 h. Lower educational attainment also predicted ring removal >2 h (OR 3.23, 95% CI 1.55–6.75). Women residing in Europe or Australia were less likely to remove the ring for >2 h compared with women in the United States (OR 0.44, 95% CI 0.24–0.83 and OR 0.13, 95% CI 0.02–0.98, respectively). Participants who reported removals >2 h were more likely to discontinue CVR use (OR 1.93, 95% CI 1.24–2.95), report dissatisfaction (OR 2.20, 95% CI 1.32–3.69) and become pregnant during the study (OR 4.07, 95% CI 1.58–10.50). Conclusions Removing the CVR for washing and removing it before intercourse are factors associated with nonadherence to ring use. These are important topics for counseling women who are considering or using vaginal rings, including the NES/EE CVR. Implications Findings from this study may be useful in guiding counseling for current and prospective vaginal ring users. Anticipatory guidance should focus on how the ring feels in the vagina and during sex. Asking about ring removals may help identify women who are at increased risk for having an unplanned pregnancy.

BACKGROUND: As part of a program to develop a novel estradiol-releasing contraceptive vaginal ring (CVR), we evaluated the pharmacokinetic (PK) profile of CVRs releasing segesterone acetate (Nestorone® (NES)) combined with one of three different estradiol (E(2)) doses. STUDY DESIGN: A prospective, double-blind, randomized, multi-centered study to evaluate a 90-day CVR releasing NES [200μg/day] plus E(2), either 10μg/day, 20μg/day, or 40μg/day in healthy reproductive-age women with regular cycles. Participants provided blood samples twice weekly for NES and E(2) levels during the first 60 days (ring 1) and the last 30 days (ring 2) of use. A subset underwent formal PK assessments at ring initiation, ring exchange (limited PK), and study completion. RESULTS: The main study enrolled 197 women; 22 participated in the PK substudy. Baseline characteristics between the main and PK participants were comparable, with an average BMI of 25.8 kg/m(2) (SD 4.3). In the PK substudy, all three rings showed similar NES PK: mean area under the curve (AUC((0-72))) 34,181 pg*day/mL; concentration maximum (Cmax) 918 pg/mL; time to maximum concentration (Tmax) 3.5 hours. For E(2,) the Cmax occurred at 2 hours, and was significantly higher with the 20 ug/day ring (mean 390 pg/mL); 10ug/day, 189 pg/mL, p = .003; 40 ug/day, 189 pg/mL, p < .001), and declined rapidly to ≤ 50 pg/mL for all doses by 24 hours. For all subjects, the median E(2) levels remained under 35 pg/mL during treatment. CONCLUSION: PK parameters of NES were not affected when paired with different doses of E(2), but E(2) levels from all three doses were lower than anticipated and no dose response was observed. IMPLICATIONS: While these novel estradiol-releasing combination contraceptive vaginal rings provided sustained release of contraceptive levels of Nestorone over 90 days, the E(2) levels achieved were not consistent with bone protection, and a dose-response was not observed.

Objectives To evaluate the effects of concurrent administration of three vaginal miconazole nitrate formulations on the absorption and exposure of Nestorone® (segesterone acetate) and ethinyl estradiol from a novel contraceptive vaginal ring (NES/EE CVR). Study design This was an open-label, randomized, crossover, drug–drug interaction study conducted over three menstrual cycles in healthy women with regular menses. We compared systemic exposure to NES and EE by determining area under the curve (AUC8–21d) with CVR only and CVR with each miconazole treatment. Three different miconazole formulations (single-dose suppository, multiple-dose suppository or multiple-dose cream) were administered in a single dose on day 8 or multiple doses on days 8–10 after CVR insertion. We evaluated safety and tolerability of the CVR in the presence of antimycotic comedication. Results Forty-five participants were randomized, and 29 completed participation. Systemic exposure to NES and EE released from the CVR increased with single or multiple doses of miconazole suppositories but not with multiple-dose cream. The maximum EE geometric mean ratio (GMR) for AUC8–21d was 1.67 (1.51–1.86) for single-dose and 1.42 (1.21–1.66) for multiple-dose suppositories. By contrast, systemic exposure to NES and EE was comparable with and without miconazole cream (all GMRs and confidence intervals within 0.80 to 1.25). Adverse events (AEs) were similar with CVR only and with all miconazole treatment groups. There were no serious treatment-related AEs. Conclusions Miconazole vaginal suppositories were associated with increased systemic levels of NES and EE, while systemic exposure with miconazole vaginal cream was comparable to no miconazole exposure. Implications Coadministration of miconazole suppositories with the investigational NES/EE CVR led to higher systemic exposure of both hormones, while coadministration with miconazole cream did not affect hormone levels. Women utilizing the NES/EE CVR may be advised to use an oral formulation or miconazole cream rather than suppository to treat vaginal candidiasis.

Our previous studies showed that intranasal delivery of progesterone offers a good bioavailability and neuroprotective efficacy after experimental stroke. We have also demonstrated that progesterone receptors (PR) are essential for cerebroprotection by endogenous progesterone and by progesterone treatment. The identification of PR as a potential drug target for stroke therapy opens new therapeutic indications for selective synthetic progestins. Nestorone® (16-methylene-17α-acetoxy-19-nor-pregn-4-ene-3, 20-dione, also known as segesterone acetate) is a 19-norprogesterone derivative that more potently targets PR than progesterone. The objective of this study was to evaluate the cerebroprotective efficiency of intranasal administration of Nestorone after middle cerebral occlusion (MCAO) in mice. We show here that intranasal administration is a very efficient route to achieve a preferential delivery of Nestorone to the brain and confers a slow elimination and a sustained bioavailability. Furthermore, intranasal administration of Nestorone (at 0.08 mg/kg) improved the functional outcomes and decreased the ischemic lesion in male but not in female mice at 48 h post MCAO. Use of PRNesCre mice, selectively lacking expression of PR in neural cells, and their control PRloxP/loxP littermates showed that the cerebroprotective effects of Nestorone in male mice depended on neural PR as they were not observed in PRNesCre mice. Our findings show that intranasal delivery of Nestorone may be an efficient strategy to promote recovery after stroke in males and confirm the key role of PR in cerebroprotection. Furthermore, they point to sex differences in the response to Nestorone treatment and emphasize the necessity to include males and females in experimental studies.

Although several progestins have been tested for hormonal male contraception, the effects of dosage and nature of various progestins on gonadotropin suppression combined with and without additional testosterone has not been performed in a comparative trial. The aim of this study was to evaluate the differential impact of four oral or transdermal progestins on the suppression of gonadotropins in healthy men: oral: cyproterone acetate (CPA), levonorgestrel (LNG), norethisterone acetate (NETA), and transdermal: Nestorone (NES), all in combination with transdermal testosterone (T). Randomized clinical trial testing was performed with four progestins at two doses each. After a 2-week progestin-only treatment, transdermal T was added for further 4 weeks and was followed by a 3-week recovery period. Progestin-dose per day: CPA 10 mg/20 mg, NES 2 mg/3 mg/dose e.g. 200/300 lg/day absorbed, NETA 5 mg/10 mg, LNG 120 lg/240 lg. From an andrology outpatient clinic, 56 healthy men aged 18–50 years, with body mass index ≤33 kg 9 m 2 were included in the study. Serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were studied. Secondary outcome measure included were serum testosterone concentrations, sperm concentrations, and safety parameters. Intergroup comparisons demonstrated that CPA and LNG had the strongest effect on LH/FSH suppression. Nevertheless, every substance showed significant inhibitory effects on gonadotropin secretion, especially in combination with transdermal T. A decrease in hematocrit and insulin sensitivity as well as cholesterol subfractions and triglycerides was uniformly seen for every group. The combination of oral or transdermal progestins with a transdermal testosterone preparation is able to suppress gonadotropins. Further dose titration studies with sperm suppression as an end-point should be conducted to determine the lowest effective dose for hormonal male contraception.

Steroid hormones regulate a variety of physiological processes, including reproductive function, and are widely used in hormonal therapy. Synthetic progestogens, or progestins, were designed to mimic progesterone (P4) for use in contraception and hormonal replacement therapy in women. Medroxyprogesterone acetate (MPA) and norethisterone (NET) are the most widely used injectable contraceptives in the developing world, while other progestins such as levonorgestrel (LNG), etonogestrel (ETG) and nestorone (NES) are used in or being developed for other forms of contraception. As concerns remain about the most appropriate choice of progestin and dosage, and the associated side-effects, the mechanisms and biological effects of progestins are frequently investigated in various in vitro mammalian cell line and tissue models. However, whether progestogens are differentially metabolised in different cell types in vivo or in vitro is unknown. For nine mammalian cell lines commonly used to investigate progestogen mechanisms of action, we developed and validated an ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) protocol for simultaneously quantifying the metabolism of the above-mentioned steroids. We show for the first time that, while 50–100% of P4 was metabolised within 24 h in all cell lines, the metabolism of the progestins is progestin- and cell line-specific. We also show that MPA and NET are significantly metabolised in human cervical tissue, but to a lesser extent than P4. Taken together, our findings suggest that differential progestogen metabolism may play a role in cell-specific therapeutic and side-effects. Relative affinities for binding to steroid receptors as well as potencies, efficacies and biocharacters for transcriptional activity of progestins, relative to P4, are most frequently determined using some of the cell lines investigated. Our results, however, suggest that differential metabolism of progestins and P4 may confound these results. In particular, metabolism may under-estimate the receptor-mediated intrinsic in vitro binding and dose-response values and predicted endogenous physiological effects of P4.

BACKGROUND Testosterone (T)/Nestorone (NES) combination gel is a potential transdermal male contraceptive that suppresses gonadotropins and spermatogenesis. Transfer of transdermal T from men to women can be prevented by washing or covering application sites with clothing. OBJECTIVES We hypothesized that showering or wearing a shirt over gel application sites would prevent secondary exposure of T and NES to a woman after close skin contact. MATERIALS AND METHODS Twelve healthy male and 12 healthy female participants were recruited. Men applied T/NES 62 mg/8 mg gel to their shoulders and upper arms. Two hours after application, female partners rubbed the application site for 15 min. Exposure in the female partner was assessed under three conditions: a shirt covered the application site; the man showered prior to skin contact; or without intervention to reduce transfer. Serum T and NES concentrations were measured by LC-MS/MS in serial blood samples for 24 h after gel exposure. MAIN OUTCOMES Change in female serum T and NES levels as measured by average concentration over 24 h (Cavg ). RESULTS Median female serum T Cavg was 23.9 ng/dL (interquartile range, 19.3, 33.9) with the shirt barrier and 26.7 ng/dL (20.7, 33.9) after showering, which was higher than baseline 20.9 ng/dL (16.7, 25.0), both p

Objectives Estrogen-sensitive hepatic proteins were assessed in women using a contraceptive vaginal ring (CVR) delivering 150 mcg Nestorone® (NES) and 15 mcg ethinyl estradiol (EE). Study design A substudy of the Contraceptive Clinical Trials Network of the National Institute of Child Health and Human Development enrolled 129 participants, with assessments of factor VIII, fibrinogen, protein S (PS) and sex hormone binding globulin (SHBG). Thirty-six participants had used combined hormonal contraceptives (CHCs) in the cycle preceding first CVR use (recent users) and 70 had no history of recent use (nonusers). Results Mean values at baseline were within the normal range for all four proteins but were higher for factor VIII, fibrinogen and SHBG and significantly lower for PS in recent compared to nonusers. During NES/EE CVR use, factor VIII, fibrinogen and PS were within the normal range; however, SHBG levels were increased by nearly 100% at Cycle 13. The change from baseline to final evaluation was statistically significant for all proteins in nonusers. The change in recent users was significant for factor VIII at Cycle 6 and for SHBG at Cycles 6 and 13, but not for PS or fibrinogen. Conclusion NES/EE CVR for up to 13 cycles was associated with changes from baseline in plasma levels of factor VIII, fibrinogen and PS that were within the normal range, with SHBG levels above the normal range by Cycle 6. Nonusers of CHC before CVR showed wider changes in values versus recent users whose baseline values were increased by previous EE exposure. Implications Recent use of CHCs demonstrated significant changes in all four measured hepatic proteins at baseline compared to nonusers. Use of the NES/EE CVR further changed these hepatic protein markers, but values remained within the normal range. Prebaseline exposure to estrogen can obscure interpretation of hepatic proteins changes associated with a second CHC.

Neurological diseases such as ischemic stroke can be debilitating and have limited treatments available. The progestin Nestorone® (segesterone acetate) has been evaluated for use in birth control and hormone replacement therapy due to its potency and high affinity for the progesterone receptor. Interestingly, Nestorone also exerts neuroprotection in animals afflicted with various central nervous system diseases, including stroke, which implicates its potential for treating these maladies in clinical settings. In fact, a recent Brain Research paper by Tanaka and colleagues demonstrates Nestorone's ability to reduce infarct sizes and preclude functional impairments in rats subjected to ischemic stroke. This commentary highlights Nestorone's properties as a progestin, its neuroprotective capabilities in animal studies, and how the Tanaka team's findings and previous clinical trials contribute to Nestorone's translation into a therapeutic agent for stroke and other neurological diseases.

To evaluate changes in the bone turnover markers CTx and P1NP during 6 months' use of novel continuous contraceptive vaginal rings delivering Nestorone (NES) 200 mcg/day and three doses of estradiol (E2) (10, 20, and 40 mcg/day).This randomized trial enrolled 189 women who used two consecutive vaginal rings over 180 days. Frequent blood sampling permitted analysis of NES, E2, CTx and P1NP concentrations. The bone-turnover marker analyses included only women with complete sampling and excluded women with characteristics that might interfere with accurate measurement of bone markers such as afternoon sampling, poor ring compliance or recent pregnancy. We evaluated the change from baseline to 6 months in CTx and P1NP, stratified by ring dose and by average circulating E2 concentrations.One hundred fifty-one women completed the study, and 82 women had complete data available for the bone marker analyses; the three dosage groups were balanced with regard to baseline characteristics. E2 concentrations remained low throughout treatment, regardless of which dose ring the participant used. Individual CTx changes from baseline averaged 27±56% (p.01). Similarly, individual P1NP changes averaged 11±33% (p=.04). These increases were within the premenopausal reference ranges, and unrelated to treatment dose or to circulating E2 concentrations.The low E2 dose of these rings was associated with low E2 concentrations and modest increases in serum bone turnover makers. Because we have only 6-month bone turnover markers and no direct evidence of bone loss or bone density change, these results must be interpreted with caution.Nestorone, a 19-norprogesterone derivative, leads to complete ovarian suppression, which should yield excellent contraceptive effectiveness. To prevent potential adverse effects on bone, the NES contraceptive ring should be combined with higher doses of E2 than were assessed in this study.

Progesterone (P4) exerts long-term neuroprotective effects in animal models of stroke, and P4 receptors play a crucial role in this neuroprotection. However, it currently remains unclear whether the activation of P4 receptors alone is sufficient to exert long-term neuroprotection because P4 exhibits other steroidogenic and GABAergic activities via several of its metabolites. Nestorone is a potent selective P4 receptor agonist without other steroidogenic and GABAergic activities. Therefore, we examined the effects of nestorone in adult male rats subjected to transient middle cerebral artery occlusion (MCAO). The dose-response relationship of nestorone showed that the 6-h post-ischemic administration of 10 μg/kg nestorone resulted in greater reductions in infarct sizes 48 h after MCAO than the other two doses tested (5 and 80 μg/kg), and this dose of nestorone significantly decreased astrocyte activation in the peri-infarct cortical region. Moreover, 10 μg/kg nestorone significantly prevented functional impairments on the 28th and 29th days and slightly reduced infarct size on the 30th day after MCAO. The present results suggest that the activation of P4 receptors alone is sufficient to exert neuroprotection against transient cerebral ischemia in adult male rats; therefore, nestorone is a promising agent in post-stroke treatment due to its potent progestational effects without other steroid-related activities.

Molecular imaging can visualize the biological processes at the molecular and cellular levels in vivo using certain tracers for specific molecular targets. Molecular imaging of breast cancer can be performed with various imaging modalities, however, positron emission tomography (PET) is a sensitive and non-invasive molecular imaging technology and this review will focus on PET molecular imaging of breast cancer, such as FDG-PET, FLT-PET, hormone receptor PET, and anti-HER2 PET.

Progesterone plays a protective role in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis (MS). Besides spinal cord neuropathology, MS patients present a dysfunctional hippocampus. In this work we studied the therapeutic effects of the progestin Nestorone in the brain of mice with chronic EAE. Nestorone decreased clinical grade and enhanced motor behavior. In addition, it increased cell proliferation and doublecortin positive neuroblasts in the hippocampus, increased GABAergic interneurons and attenuated the number of Iba1+ microglia/macrophages, events possibly linked to enhancement of neurogenesis. Therefore, Nestorone protected against hippocampus abnormalities and improved functional outcomes of EAE mice, suggesting its potential value for MS. Fil: Garay, Laura Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina Fil: Gonzalez Deniselle, Maria Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Sitruk Ware, Regine. Population Council’s Center for Biomedical Research; Estados Unidos. The Rockefeller University; Estados Unidos Fil: Gennoun, Rachida. Inserm; Francia Fil: Shumacher, Michael. Inserm; Francia Fil: Alejandro de Nicola. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina

Fifty percent of pregnancies in the United States are unintended despite numerous contraceptive methods available to women. The only male contraceptive methods, vasectomy and condoms, are used by 10% and 16% of couples, respectively. Prior studies have shown efficacy of male hormonal contraceptives in development, but few have evaluated patient acceptability and potential use if commercially available. The objective of this study is to determine if a transdermal gel-based male hormonal contraceptive regimen, containing testosterone and Nestorone® gels, would be acceptable to study participants as a primary contraceptive method.As part of a three-arm, 6-month, double-blind, randomized controlled trial of testosterone and nestorone gels at two academic medical centers, subjects completed a questionnaire to assess the acceptability of the regimen. Of the 99 men randomized, 79 provided data for analysis.Overall, 56% (44/79) of men were satisfied or extremely satisfied with this gel-based method of contraception, and 51% (40/79) reported that they would recommend this method to others. One third of subjects (26/79) reported that they would use this as their primary method of contraception if it were commercially available today. However, men with concerns about sexually transmitted disease were significantly less satisfied than men without such concerns (p=0.03).A majority of the men who volunteered to participate in this trial of an experimental male hormonal contraceptive were satisfied with this transdermal male hormonal contraceptive. If commercially available, a combination of topical nesterone and testosterone gels could provide a reversible, effective method of contraception that is appealing to men.A substantial portion of men report they would use this transdermal male contraceptive regimen if commercially available. This method would provide a novel, reversible method of contraception for men, whose current choices are limited to condoms and vasectomy.

Nestorone® (NES) is a potent nonandrogenic progestin being developed for contraception. NES is a synthetic progestin that may possess neuroprotective and myelin regenerative potential as added health benefits. In receptor transactivation experiments, NES displayed greater potency than progesterone to transactivate the human progesterone receptor (PR). This was confirmed by docking experiments where NES adopts the same docking position within the PR ligand-binding domain (LBD) as progesterone and forms additional stabilizing contacts between 17α-acetoxy and 16-methylene groups and PR LBD, supporting its higher potency than progesterone. The analog 13-ethyl NES also establishes similar contacts as NES with Met909, leading to comparable potency as NES. In contrast, NES is not stabilized within the human androgen receptor LBD, leading to negligible androgen receptor transactivation. Because progesterone acts in the brain by both PR binding and indirectly via binding of the metabolite allopregnanolone to γ-aminobutyric acid type A receptor (GABAAR), we investigated if NES is metabolized to 3α, 5α-tetrahydronestorone (3α, 5α-THNES) in the brain and if this metabolite could interact with GABAAR. In female mice, low concentrations of reduced NES metabolites were identified by gas chromatography/mass spectrometry in both plasma and brain. Electrophysiological studies showed that 3α, 5α-THNES exhibited only limited activity to enhance GABAAR-evoked responses with WSS-1 cells and did not modulate synaptic GABAARs of mouse cortical neurons. Thus, the inability of reduced metabolite of NES (3α, 5α-THNES) to activate GABAAR suggests that the neuroprotective and myelin regenerative effects of NES are mediated via PR binding and not via its interaction with the GABAAR.

Implantable gynecological drug delivery devices are applied for contraceptive, hormone replacement purposes and for the treatments of other gynecological diseases, e.g. endometriosis. The review provides a comprehensive overview about the indications, advantages, limitation of application and the applied technologies of hormone-containing implants, as well. The study comprises the relevant patents and the recently published papers.

Progestins used in contraception and hormone replacement therapy are synthetic compounds designed to mimic the actions of the natural hormone progesterone and are classed into four consecutive generations. The biological actions of progestins are primarily determined by their interactions with steroid receptors, and factors such as metabolism, pharmacokinetics, bioavailability and the regulation of endogenous steroid hormone biosynthesis are often overlooked. Although some studies have investigated the effects of select progestins on a few steroidogenic enzymes, studies comparing the effects of progestins from different generations are lacking. This study therefore explored the putative modulatory effects of progestins on de novo steroid synthesis in the adrenal by comparing the effects of select progestins from the respective generations, on endogenous steroid hormone production by the H295R human adrenocortical carcinoma cell line. Ultra-performance liquid chromatography/tandem mass spectrometry analysis showed that the fourth-generation progestins, nestorone (NES), nomegestrol acetate (NoMAC) and drospirenone (DRSP), unlike the progestins selected from the first three generations, modulate the biosynthesis of several endogenous steroids. Subsequent assays performed in COS-1 cells expressing human 3βHSD2, suggest that these progestins modulate the biosynthesis of steroid hormones by inhibiting the activity of 3βHSD2. The Ki values determined for the inhibition of human 3βHSD2 by NES (9.5 ± 0.96 nM), NoMAC (29 ± 7.1 nM) and DRSP (232 ± 38 nM) were within the reported concentration ranges for the contraceptive use of these progestins in vivo. Taken together, our results suggest that newer, fourth-generation progestins may exert both positive and negative physiological effects via the modulation of endogenous steroid hormone biosynthesis.

Progesterone receptors (PR) are expressed throughout the brain. However, their functional significance remains understudied. Here we report a novel role of PR as crucial mediators of neuroprotection using a model of transient middle cerebral artery occlusion and PR knockout mice. Six hours after ischemia, we observed a rapid increase in progesterone and 5-dihydroprogesterone, the endogenous PR ligands, a process that may be a part of the natural neuroprotective mechanisms. PR deficiency, and even haploinsufficiency, increases the susceptibility of the brain to stroke damage. Within a time window of 24 h, PR-dependent signaling of endogenous brain progesterone limits the extent of tissue damage and the impairment of motor functions. Longer-term improvement requires additional treatment with exogenous progesterone and is also PR dependent. The potent and selective PR agonist Nestorone is also effective. In contrast to progesterone, levels of the neurosteroid allopregnanolone, which modulates -aminobutyric acid type A receptors, did not increase after stroke, but its administration protected both wild-type and PR-deficient mice against ischemic damage. These results show that 1) PR are linked to signaling pathways that influence susceptibility to stroke, and 2) PR are direct key targets for both endogenous neuroprotection and for therapeutic strategies after stroke, and they suggest a novel indication for synthetic progestins already validated for contraception. Although allopregnanolone may not be an endogenous neuroprotective agent, its administration protects the brain against ischemicdamageby signaling mechanisms not involving PR. Collectively, our data clarify the relative roles of PR and allopregnanolone in neuroprotection after stroke. Fil: Liu, Ailing. Institut National de la Santé et de la Recherche Médicale; Francia. Université Paris Sud; Francia Fil: Margaill, Isabelle. Institut National de la Santé et de la Recherche Médicale; Francia. Universite de Paris V; Francia. University Paris Descartes; Francia Fil: Zhang, Shaodong. Institut National de la Santé et de la Recherche Médicale; Francia. Université Paris Sud; Francia Fil: Labombarda, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina Fil: Coqueran, Bérard. Institut National de la Santé et de la Recherche Médicale; Francia. Universite de Paris V; Francia Fil: Delespierre, Brigitte. Université Paris Sud; Francia. Institut National de la Santé et de la Recherche Médicale; Francia Fil: Liere, Philippe. Université Paris Sud; Francia. Institut National de la Santé et de la Recherche Médicale; Francia Fil: Marchand Leroux, Catherine. Institut National de la Santé et de la Recherche Médicale; Francia. Universite de Paris V; Francia Fil: O’Malley, Bert W.. Baylor College of Medicine; Fil: Lydon, John P.. Baylor College of Medicine; Fil: de Nicola, Alejandro Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina Fil: Sitruk Ware, Regine. The Rockefeller University; Estados Unidos Fil: Mattern, Claudia. MetP Pharma AG; Suiza Fil: Plotkine, Michel. Universite de Paris V; Francia Fil: Schumacher, Michael. Institut National de la Santé et de la Recherche Médicale; Francia. Université Paris Sud; Francia Fil: Guennoun, Rachida. Université Paris Sud; Francia. Institut National de la Santé et de la Recherche Médicale; Francia

Nomegestrol acetate (NOMAC) is a 19-norprogesterone derivative with high biological activity at the progesterone receptor, a weak anti-androgenic effect, but with no binding to estrogen, glucocorticoid or mineralocorticoid receptors. At dosages of 1.5 mg/day or more, NOMAC effectively suppresses gonadotropic activity and ovulation in women of reproductive age. Hemostasis, lipids and carbohydrate metabolism remain largely unchanged. In normal and cancerous human breast cells, NOMAC has shown favorable effects on estrogen metabolism. Like natural progesterone (but in contrast to some other synthetic progestogens), it does not appear stimulate the proliferation of cancerous breast cells. While there has been some experience of the use of NOMAC in combination with estrogens as a hormone replacement therapy, most of the data on the compound are reported in the context of its inclusion as a component of a new contraceptive pill comprising 2.5 mg NOMAC combined with 1.5 mg estradiol. Because of its strong endometrial efficacy, and due to its high antigonadotropic activity and long elimination half-life (about 50 h), the contraceptive efficacy of the new pill is maintained even when dosages are missed. Furthermore, for the first time with a monophasic 24/4 regimen containing estradiol, cyclical stability can be achieved comparable with that obtained using pills containing ethinyl estradiol and progestogens like levonorgestrel or drospirenone. The addition of NOMAC to estradiol means that the beneficial effects of estrogen are not lost, which is of especial importance in relation to the cardiovascular system. On the basis both of its pharmacology and of studies performed during the development of the NOMAC/estradiol pill, involving some 4000 women in total, good long-term tolerability can be expected for NOMAC, although its safety profile is still to be fully ascertained, as the clinical endpoint studies are yet to be completed.

A synthetic progestin Nestorone is being developed for female-contraception. This study was conducted to determine the distribution metabolism and excretion of tritium-labeled Nestorone ((3)H Nestorone) in adult female rats. Rats were injected subcutaneously (S.C.) with a single dose of 400 microCi (3)H Nestorone/kg BW. Its distribution and concentrations in blood plasma and other tissues were determined at defined times. The excreta were examined for elimination of (3)H Nestorone. Radioactivity in all samples was analyzed by liquid scintillation counter. Metabolite profiling was performed by HPLC and LC/MS analysis of the plasma urine and feces samples. Following subcutaneous injection of (3)H Nestorone the mean peak concentrations of radioactivity (C(max)) in the blood and plasma were 58.1 and 95.5 ng equiv. (3)H Nestorone/g respectively at 2-h postdose (T(max)). Thereafter the concentration of drug steadily declined through 96-h postdose with a terminal elimination half-life (t(1/2)) of 15.6 h. (3)H Nestorone-derived radioactivity was widely distributed in most tissues by 0.5 h and attained a mean maximal concentration by 2-h postdose. Approximately 81.4% and 7.62% of the administered dose was excreted via feces and urine respectively. In vivo metabolism of (3)H Nestorone resulted into a total of 19 metabolites. Among them two metabolites viz. 17alpha-deacetyl-Nestorone (M9) and 45-dihydro-17alpha-deacetyl-Nestorone (M19) were identified by HPLC and LC/MS analysis. Metabolite profiling of plasma samples showed that most of the circulating radioactivity was associated with unchanged parent drug and M19. The M19 was a major metabolite in the profiled urine and feces samples. Presence of large proportion of drug/drug-related material in feces suggested that the biliary excretion is a main elimination route of (3)H Nestorone. The distribution metabolism and excretion profiles of (3)H Nestorone obtained in this study provide a fairly good insight about its fate in women. Copyright 2010 Elsevier Inc. All rights reserved.

19-nor-progesterone (19-nor-P) has the characteristics of a potent mineralocorticoid in adrenalectomized or salt-loaded rats and is capable of causing hypertension. In human placenta, progesterone is converted to 19-hydroxy-progesterone, a precursor of 19-nor-P. In some states of pregnancy hypertension, 19-nor-P may inhibit renal 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), thus allowing cortisol to bind to the mineralocorticoid receptor (MR). Therefore, we investigated the ability of 19-nor-P to inhibit human 11beta-HSD2. Fetal kidney cells (HEK 293) were transfected with human 11beta-HSD2 and incubated with increasing concentrations of 19-nor-P, labelled and unlabelled cortisol. Steroids were extracted, separated by TLC, and radioactivity was measured using a TLC scanner. 19-nor-P treatment did not significantly reduce 11beta-HSD2 activity (430 to 300 pmol/mg protein/h) in the range of tested concentrations. In conclusion, 19-nor-P did not inhibit human 11beta-HSD2 and seems not to be involved in human hypertension. Nevertheless, 19-nor-P may be converted by extra-adrenal tissues into 19-nor-deoxycorticosterone (DOC) or 19-nor-corticosterone, which are potent mineralocorticoids and may be involved in the pathogenesis of hypertension during pregnancy.

Objective: We evaluated the effects of a new combined hormonal contraceptive vaginal ring (CVR) delivering the nonandrogenic progestin Nestorone® (NES) and ethinyl estradiol (EE) on several key estrogen-sensitive hepatic proteins that may be markers for the risk of arterial or venous disease events and on blood pressure (BP). Because the pharmacologic androgenicity of the progestin in these formulations influences the hepatic impact of EE, we selected an oral contraceptive (OC) delivering the androgenic progestin levonorgestrel (LNG) and EE as the comparator. We also investigated the effect of delivery route, which is known to modify the hepatic effects of estradiol, but has not been widely studied with EE. Study Methods: Women, aged 18-34 years, with no contraindications to the use of combined OCs, were randomized to three cycles of treatment with a CVR delivering NES/EE (150/15 μg/day) or a combined OC providing LNG and EE (150/30 μg per tablet). Each cycle consisted of 21 days of active treatment, followed by 7 days without treatment. During the last weeks of the pretreatment and third treatment cycles, blood samples were obtained for determinations of plasma concentrations of angiotensinogen, an estrogen-sensitive hepatic protein, and serum concentrations of sex hormone-binding globulin (SHBG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and estrogen- and androgen-sensitive proteins. BP was also measured. Results: Of 47 women randomized, 45 completed the study (CVR: 23; OC: 22). Within-group comparisons over time by repeated-measure analysis of variance demonstrated statistically significant changes over time with both treatments for all hepatic proteins (p

Wobbler mutant mice suffer from progressive motoneuron degeneration and glial cell reactivity in the spinal cord. To prevent development of these abnormalities, we employed Nestorone, a high-affinity progesterone receptor agonist endowed with neuroprotective, promyelinating and anti-inflammatory activities in experimental brain ischemia, preventing neuroinflammation and chemical degeneration. Five-month-old Wobbler mice (wr-/wr-) received s.c. injections of 200μg/day/mouse of Nestorone in vegetable oil or vehicle for 10days. Control NFR/NFR mice (background strain for Wobbler) received vehicle only. Vehicle-treated Wobblers showed typical spinal cord abnormalities, such as vacuolated motoneurons, decreased immunoreactive choline-acetyltransferase, decreased expression of glutamine synthase (GS), increased glial fibrillary acidic protein-positive (GFAP) astrogliosis and curved digits in forelimbs. These cell-specific abnormalities were normalized in Nestorone-treated Wobblers. In addition, vehicle-treated Wobblers showed Iba1+ microgliosis, high expression of the microglial marker CD11b mRNA and up-regulation of the proinflammatory markers TNFα and iNOS mRNAs. In Nestorone-treated Wobblers, Iba1+ microgliosis subsided, whereas CD11b, TNFα and iNOS mRNAs were down-regulated. NFκB mRNA was increased in Wobbler spinal cord and decreased by Nestorone, whereas expression of its inhibitor IκBα was increased in Nestorone-treated Wobblers compared to control mice and vehicle-treated Wobblers. In conclusion, our results showed that Nestorone restraining effects on proinflammatory mediators, microgliosis and astrogliosis may support neurons in their resistance against degenerative processes Fil: Meyer, Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina Fil: Gonzalez Deniselle, Maria Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Garay, Laura Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Sitruk Ware, Regine. The Rockefeller University; Estados Unidos. Population Council; Estados Unidos Fil: Guennoun, Rachida. Inserm; Francia. Universite Paris Sud; Francia Fil: de Nicola, Alejandro Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina

Despite numerous contraceptive options available to women, approximately half of all pregnancies in the United States and worldwide are unplanned. Women and men support the development of reversible male contraception strategies, but none have been brought to market. Herein we review the physiologic basis for male hormonal contraception, the history of male hormonal contraception development, currents agents in development, as well as the potential risks and benefits of male hormonal contraception for men.

Objective This study aims to determine the lowest effective of three Nestorone (NES)/estradiol (E2) transdermal gel doses to ensure ovulation suppression in 90–95% of cycles. Methods This was a randomized, open-label, three-treatment-period cross-over study to evaluate the effects of NES/E2 transdermal gel on ovulation inhibition, suppression of follicular growth and pharmacokinetic parameters. The doses were low (1.5 mg NES/0.5 mg E2), medium (3.0 mg NES/1.0 mg E2) and high (4.5 mg NES/1.5 mg E2). Participants applied gel daily to a fixed area on the abdomen for 21 consecutive days. They were interviewed regarding their experiences using the gel. Results Eighteen participants were randomized; 16 completed the study. Median NES Cmax values for low, medium and high dose groups at day 21 were 318.6 pmol/L, 783.0 pmol/L and 1063.8 pmol/L, respectively. Median maximum follicular diameter was higher with the lowest dose with 16.2 mm versus 10.0 and 10.4 mm with the medium and high doses, respectively. Among adherent participants, ovulation was inhibited in all dose groups, except for one participant in the medium dose (6.7%) that had luteal activity and an ultrasound image suggestive of a luteinized unruptured follicle. There were few reports of unscheduled bleeding, with more episodes reported for the lower dose. Adverse events were mild, and no skin irritation was reported from gel application. Conclusion While all three doses blocked ovulation effectively and were evaluated as safe and acceptable, the medium dose was considered the lowest effective dose based on a more adequate suppression of follicular development. Further development of this novel contraceptive delivering NES and E2 is warranted and has potential for improved safety compared to ethinyl-estradiol-based methods.

Objective: We examined the clinical performance of contraceptive vaginal rings (rings) delivering Nestorone (NES) progestin and ethinyl estradiol (EE). Ring removal times were signaled by menstrual events. Bleeding patterns adverse events patterns of use and continuation rates were the principal parameters evaluated. Methods: In a two-stage 6-month trial subjects were randomized to use rings releasing 50 µg/day of NES and either 10 (50/10) or 20 (50/20) µg/day of EE. Subjects were to keep rings continuously in situ until menstrual bleeding or prolonged spotting-signaled removal. Reinsertion was to occur 96 h later. After the randomized stage an open-label 6-month trial of rings releasing 150 µg/day of NES and 15 µg/day of EE (150/15) began with the same menstrually signaled regimen. Results: Two-hundred forty-six subjects participated in the trial. Six-month pregnancy rates ranged by ring dose from 1.3 to 3.9 per 100. For each ring dose combination 6-month continuation rates were above 80 per 100. Bleeding and spotting (B+S) days in women with the 50 µg/day NES rings were similar in number to those experienced by cycling women not using contraception. Nevertheless in the initial 90 days fewer B+S days were reported by subjects with the 50/20 ring than by subjects with the 50/10 ring (p

The implant containing Nestorone is a promising long-acting contraceptive especially suitable for lactating women. In this study, two experiments were designed to observe the effect of Nestorone on the gonadotropic cells in pituitary of rats for analyzing its antiovulation mechanism. In the first experiment, the ED 50 of Nestorone on inhibiting ovulation was found to be 1.32 mg/kg. The serum luteinizing hormone (LH) levels were significantly lower 60 h after being treated with Nestorone at 8:30–9:00 a.m. on Day 2 (D2) of estrus. Image analysis showed that the average size of the LH cells in groups treated with Nestorone at 2 or 4 mg/kg was larger than that of the control. In the group treated with 4 mg/kg, most of gonadotropic cells were regular round in shape. And, abundant granules in cytoplasm were found in those cells, which indicated that the LH stored in cells was not released. In the second experiment, the rats were treated with Nestorone at 5 mg/kg at 11:30–12:00 a.m. on D2 of estrus. The normal or higher expression of LHβ mRNA in pituitary suggested that the synthesis of LH was not inhibited by the treatment with Nestorone. The expression of PR mRNA in pituitary was significantly lower than that of the control at 33 h after treatment. This might be a direct effect of Nestorone, since there were no differences in the serum E 2 and P 4 levels between the treated and the control group. It is concluded that Nestorone prevents ovulation through inhibition of LH secretion and it has no effect on synthesis of LH. Progesterone receptors in pituitary might be involved in this process, but further study is needed to gain more evidence.

A 2-year trial of a single Nestorone® (NES) rod implant was conducted at three Latin American centers, each enrolling 100 women. We studied the safety, effectiveness and acceptability of this progestin-releasing contraceptive implant. Three pregnancies occurred, the last at 18 months of use. Because no pregnancies were expected in the first 18 months, the trial was halted. At that time, 224 women had completed at least 18 months of use, and 99 women had used the implant for more than 24 months. Few participants used adjunctive contraception between the time the study was halted and the time they had their implant removed. No additional pregnancies occurred before the removal of the last implant. The 2-year cumulative pregnancy rate was 1.7 per 100 with a Pearl index of 0.6 per 100 for the 2-year period. The 1-year and 2-year continuation rates were 80.5 and 66.7 per 100, respectively. Menstrual and medical disturbances were the principal reasons for discontinuation, followed by planned pregnancy. Headache and weight gain frequently led to discontinuation. The NES implant had little important effect on most clinical chemistry and lipid parameters. Over the study course, the mean change in hemoglobin was

The 19-nor derivatives of progesterone are referred to as “pure” progestational molecules as they bind almost exclusively to the progesterone receptor (PR) without interfering with receptors of other steroids. In this category is Nestorone ® , which has strong progestational activity and antiovulatory potency with no androgenic or estrogenic activity in vivo. These properties make it highly suitable for use in contraception and hormonal therapy (HT). Due to its high potency, very low doses of Nestorone may be delivered via long-term sustained-release delivery systems. Nestorone, 75 or 100 μg per day, released by vaginal ring has suppressed ovulation in women, with inhibition of follicular maturation. A vaginal ring releasing both 150 μg of Nestorone and 15 μg of ethinyl estradiol per day has effectively suppressed ovulation for 13 consecutive cycles. Nestorone has also been used effectively in a single implant for contraception in breastfeeding women and shows promise for use in transdermal systems as a contraceptive or for HT when combined with estrogen.

To evaluate the efficacy of three different doses of Nestorone progestin administered by implants for relief of pain, as well as bleeding patterns and symptoms in women with endometriosis.An open clinical study without a control group.Twenty-one women in whom endometriosis was diagnosed and treated at laparoscopy or at laparotomy.The patients were randomly allocated to one of three groups receiving a daily dose of either 150 micro g, 200 micro g or 400 micro g Nestorone for two to four implants inserted subcutaneously for 7 months. After removal of the implants the follow-up period was 6 months. Six patients in the 150 micro g group, seven in the 200 micro g group and five in the 400 micro g group completed the study.Records of bleeding and registered side-effects and endometriosis-related symptoms were kept by the patients. Ovarian status was evaluated by vaginal ultrasonography. Serum concentrations of Nestorone and of lipids were measured.Pelvic pain decreased significantly in response to the treatment in all groups but returned to pretreatment levels during the post-treatment period. Bleeding and spotting was the most common side-effect followed by hypoestrogenic and psychic symptoms, with no significant difference among the groups. No significant changes in the serum levels of total, HDL or LDL cholesterol were found. One patient during the treatment period and four patients during the follow ups underwent surgical procedures.All three doses of Nestorone effectively alleviated endometriosis-related pain. While the Nestorone implant provides an interesting option for the treatment of endometriosis-related pain, its role needs to be assessed in comparative trials.

Estrogen replacement therapy is associated with improvement of cognitive deficits and reduced incidence of Alzheimer's disease. To compare the impact of therapeutically relevant progestins on estrogen-induced neuroprotection, we treated primary hippocampal neuron cultures with 17beta-E2 and progestin, alone and in combination, 48 h before glutamate insult. Estrogen, progesterone, and 19-norprogesterone, alone or in combination, protected against glutamate toxicity. In contrast, medroxyprogesterone acetate (MPA) failed to protect against glutamate toxicity. Not only was MPA an ineffective neuroprotectant but it attenuated the estrogen- induced neuroprotection when coadministered. We addressed the role of MAPK activation in neuroprotection by ovarian steroids. Estrogen and all three progestins tested, alone or in combination, activated MAPK, indicating another mechanism of protection. Bcl-2 expression has been shown to prevent cell death and is up-regulated by 17beta-E2. Progesterone and 19-norprogesterone, alone or in combination with estrogen, increased Bcl-2 expression. In contrast, MPA blocked estrogen-induced Bcl-2 expression when coadministered. These results may have important implications for the effective use of hormone replacement therapy in the maintenance of neuronal function during menopause and aging and for protection against neurodegenerative diseases such as Alzheimer's disease.

Fluorine-18-labeled steroid receptor tracers, 16α-[(18)F]fluoroestradiol (FES), [(18)F]fluoro furanyl norprogesterone (FFNP), and 16β-[(18)F]fluoro-5α-dihydrotestosterone (FDHT), are important imaging tools for studies of breast and prostate cancers using positron emission tomography (PET). The automated production of these ligands with high specific activity (SA) as radiopharmaceuticals requires modification and optimization of the currently reported methods. [(18)F]FES with high SA was synthesized in over 60% radiochemical yield (RCY) at the end of synthesis (EOS) using a small amount of precursor (1) (as low as 0.3 mg) and 1 M H2SO4 for deprotection of the intermediate (2). [(18)F]FFNP was synthesized in up to 77% RCY at EOS using the triflate precursor (4) at room temperature or in 25% RCY using the mesylate precursor (6) at 65°C. Both methods are highly reproducible and afford high SA. [(18)F]FDHT was synthesized by radiofluoride incorporation at room temperature, reduction with NaBH4 , and deprotection with HCl/acetone, giving [(18)F]FDHT in up to 75% yield (RCY). All of these methods can be easily translated to automated production. The information provided here will aid in the development of automated production of these steroid receptor tracers with high or improved yields, optimal SA, and ease of processing for research and clinical use.

Objectives Develop and test a theoretical acceptability model for the Nestorone®/ethinyl estradiol contraceptive vaginal ring (CVR); explore whether domains of use within the model predict satisfaction, method adherence and CVR continuation. Study Design Four domains of use were considered relative to outcome markers of acceptability, that is, method satisfaction, adherence and continuation. A questionnaire to evaluate subjects' experiences relative to the domains, their satisfaction (Likert scale) and adherence to instructions for use was developed and administered to 1036 women enrolled in a 13-cycle Phase 3 trial. Method continuation was documented from the trial database. Stepwise logistic regression (LR) analysis was conducted and odds ratios (ORs) calculated to assess associations of satisfaction with questions from the four domains. Fisher's Exact Test was used to determine the association of satisfaction with outcome measures. Results A final acceptability model was developed based on the following determinants of CVR satisfaction: ease of use, side effects, expulsions/feeling the CVR and sexual activity including physical effects during intercourse. Satisfaction was high (89%) and related to higher method adherence [OR, 2.6 (1.3, 5.2)] and continuation [OR, 5.5 (3.5, 8.4)]. According to the LR analysis, attributes of CVR use representing items from the four domains — finding it easy to remove, not complaining of side effects, not feeling the CVR while wearing it and experiencing no change or an increase in sexual pleasure and/or frequency — were associated with higher odds of satisfaction. Conclusion Hypothesized domains of CVR use were related to satisfaction, which was associated with adherence and continuation. Results provide a scientific basis for introduction and future research. Implications Statement Acceptability research is important when introducing a new method of contraception and determining whether it can be a successful option in meeting the reproductive health needs of women and men. This study was designed to test a conceptual model of acceptability and identify factors associated with successful use of a new contraceptive delivery modality. Original research was conducted for this publication.

Progestin hormones stimulate sperm motility in teleosts but their mechanisms of action remain unclear. Preliminary results suggest that progestin upregulation of sperm motility in southern flounder and several other marine species is mediated through a sperm membrane progestin receptor with the characteristics of membrane progestin receptor alpha (mPRα, also known as Paqr7b). The hypothesis that mPRα has an important role in progestin regulation of southern flounder sperm motility and fertility was tested in the present study. The specific mPRα agonist, 10-ethenyl-19-norprogesterone (Org OD 02-0, 100nM), mimicked the stimulatory actions of the endogenous progestin, 17,20β, 21-trihydroxy-4-pregnen-3-one (20β-S, 100nM) on flounder sperm motility. The concentration of the mPRα protein on sperm plasma membranes was positively correlated to sperm motility as well as the responsiveness of sperm to progestin stimulation. Acute in vitro progestin treatment of sperm with high mPRα protein levels increased both sperm motility and fertilization success in strip spawning experiments. However, in vitro progestin treatments were ineffective on sperm with low receptor abundance. A single injection of the superactive gonadotropin-releasing hormone analog (LHRHa, 100μg/kg) increased sperm motility and fertilization success in strip spawning experiments 72h post-injection which was accompanied by an increase in mPRα protein concentrations on sperm plasma membranes. These results provide clear evidence that southern flounder sperm hypermotility is mediated through mPRα. Stimulatory G proteins, but not inhibitory G proteins, were identified in flounder sperm plasma membrane fractions. The finding that treatment of flounder sperm plasma membrane fractions with either 20β-S or Org OD 02-0 increases cAMP levels suggests progestins stimulate flounder sperm motility by activating an mPRα/stimulatory G protein/membrane adenylyl cyclase pathway. A similar mechanism has been identified in Atlantic croaker, suggesting that the signaling pathway mediated by mPRα in sperm is highly conserved in advanced teleosts. Collectively, our results indicate that progestin-stimulation of flounder sperm hypermotility and fertility is dependent on a sufficient concentration of mPRα which can be upregulated by in vivo LHRHa treatments. These findings potentially have practical applications for enhancing the fertility of male flounder broodstock.

The progestational activity of second- and third-generation progestins in oral contraceptives were markedly increased by addition of an 18-methyl group. A new progestin, the 18-methyl analog of Nestorone, 16-methylene-17alpha-hydroxy-18-methyl-19-norpregn-4-ene-3,2 0-dione acetate (10), was synthesized. The relative binding affinity and biologic activity of 10 was compared with Nestorone, levonorgestrel, and progesterone using a binding assay for rat progesterone receptors, the Clauberg assay in the rabbit, and by assessing pregnancy maintenance in the rat. These studies, as summarized in Table 4, show that 10 is three to ten times more potent than Nestorone. The addition of the 18-methyl group to Nestorone markedly increased its potency as noted above, but is unlikely to change its rate of delivery from sustained release systems. 10 should be ideally suited for administration by implants or small skin patches.

Changes to the pattern of menstrual bleeding are almost universal in women using progestogen-only methods of contraception, and are an important cause of discontinuation of these methods. The present study was designed to explore the changes in menstrual bleeding patterns and objectively measure menstrual blood loss (MBL) in 110 women before and during one year of use of 4 different progestogen-only contraceptives: Norplant subdermal levonorgestrel implants; Nestorone progestogen 4-cm or 6-cm implants nominally delivering 100 microg or 150 microg daily; or a vaginal ring (CVR) delivering 100 microg of Nestorone (NES) daily (CVR users were limited to only 6 months of use). Groups could not be directly compared because of the differences in numbers of subjects and durations of treatment. The total MBL during each of the three 8-week collection periods during treatment decreased significantly in each group compared to the total blood loss in the two control cycles (greater than 50% decrease in all groups during the first 6 months), although the differences between individual women at the extremes remained considerable. The highest blood loss measured on any single day during the treatment collection periods was significantly reduced (p0.001) in users of all four devices in all three collection periods compared to the control period (CVR users did not have a 3rd collection period). The Nestorone-releasing CVR was associated with an 88% reduction in mean MBL and a high incidence of amenorrhea at 6 months. There was considerable variation in percentage reduction in total blood loss at 6 and 12 months between individual women ranging from 100% (women with amenorrhea) to a small minority experiencing an increase compared with control cycles. The increases in measured blood loss during treatment were almost entirely in women with light bleeding in the control period and were related to prolonged episodes of light bleeding rather than heavy bleeding. Women contemplating use of a progestogen-only contraceptive method need to be counseled about alterations to the menstrual cycle but can be reassured that total blood loss will usually be much less than with normal cycles.

Vaginal inspections using colposcopy before insertion of contraceptive vaginal rings and at 2-month intervals during ring use were conducted on 169 users of four different formulations. The rings studied released Nestorone alone (50, 75, 100 g daily over 6 months); ethinyl estradiol: Nestorone (30:100 and 15:150 g daily over 6 months); ethinylestradiol:norethindrone acetate (20:1000 and 15:1000 g daily over 4 months); and ethinyl estradiol:norethindrone acetate (20:1000 g daily over 12 months). A total of 88 altered or atypical conditions of the vaginal surface appearance were recorded in 507 inspections (17.4% of inspections). Many of these atypical appearances were quite subtle. The incidence was significantly higher (p0.01) than in the single pretreatment examinations (11 in 158 inspections; 7.0%), but closely matched that of a "control group" of sexually active women who were the subject of an earlier study by the same investigators. In that study, the incidence was 18% (57 atypical conditions in 317 inspections). In all, 83% of atypical conditions identified in the vagina during ring use had disappeared by the next scheduled colposcopy despite continued ring use. Findings of potential significance were conservatively defined as all ulcerations, those abrasions and ecchymoses that were0.5 cm in any direction, and fields of five or more petechiae. Findings fitting those criteria comprised 30% of atypical conditions in ring users, 33% in the control group, and 27% pretreatment. The corresponding incidence as a percentage of inspections were 5.3%, 6. 0%, and 2.5% in the ring users, control groups, and pretreatment groups, respectively. These differences were not statistically significant. The findings suggest that the vaginal rings included in the studies contributed little, if at all, to clinically significant lesions or to total lesion incidence. Further definition would require a larger and longer-term study with matched controls.