Effects of a monophasic combined oral contraceptive containing nomegestrol acetate and 17 beta-oestradiol on ovarian function in comparison to a monophasic combined oral contraceptive containing drospirenone and ethinylestradiol

A review of the pharmacology, clinical outcomes, and real-world effectiveness, safety, and non-contraceptive effects of NOMAC/E2

Selecting an appropriate oral contraceptive can be challenging for healthcare professionals due to the abundance of marketed contraceptive options with different clinical and real-world effectiveness and safety profiles. Nomegestrol acetate + 17β-estradiol (NOMAC/E2) is a combined oral contraceptive (COC) that inhibits ovulation by suppressing ovarian function by a 17-hydroxy-progesterone derivative and an estrogen identical to that endogenously produced by the ovaries. This narrative review examines clinical and real-world studies of NOMAC/E2 based on a background literature search using PubMed and Google Scholar. The review outlines the pharmacology of NOMAC/E2, including its progestational activity, pharmacokinetics, and effects on carbohydrate metabolism, lipid metabolism, and coagulation parameters, and summarizes key clinical efficacy and safety data that led to the approval of NOMAC/E2 in Europe, Brazil, and Australia. To help elucidate how NOMAC/E2 clinical trial data translate into a real-world setting, this review describes the effectiveness and safety of NOMAC/E2 in prospective studies that include over 90,000 users (half of whom received NOMAC/E2), outlining its effects on risk of thrombosis, menstrual bleeding patterns, weight, mood, acne, bone health, and patient quality of life. Non-contraceptive benefits of NOMAC/E2 for women with endometriosis, dysmenorrhea, or pre-menstrual dysphoric disorder are also discussed. These data demonstrate that NOMAC/E2 has a long half-life and rapid absorption, is effective at preventing unwanted pregnancies, and exhibits a favorable safety profile in both clinical trials and real-world settings. Importantly, NOMAC/E2 is not associated with increased risk of venous thromboembolism, a major safety concern of healthcare professionals for women receiving hormonal contraceptives. This review highlights NOMAC/E2 as a differentiated option among COCs and could help inform oral contraceptive choice to ultimately improve patient management and outcomes in real-world settings.

Estradiol Valerate vs Ethinylestradiol in Combined Oral Contraceptives: Effects on the Pituitary-Ovarian Axis

CONTEXT

Limited studies have compared the effects of combined oral contraceptives (COCs) containing natural estrogens and synthetic ethinylestradiol (EE) on reproductive hormones.

OBJECTIVE

To compare estradiol valerate (EV) + dienogest (DNG), EE + DNG, and DNG alone (active control) on levels of follicle stimulating hormone (FSH), luteinizing hormone, anti-Müllerian hormone (AMH), ovarian steroids, sex hormone binding globulin (SHBG), and the free androgen index (FAI).

METHODS

This spin-off study from a randomized trial enrolled 59 healthy, 18 to 35-year-old ovulatory women, outpatients at Helsinki and Oulu University Hospitals, Finland, who were randomized to EV 2 mg + DNG 2-3 mg (n = 20); EE 0.03 mg + DNG 2 mg (n = 20); and DNG 2 mg (n = 19) for 9 weeks. Blood samples were drawn at baseline, and at 5 and 9 weeks. Age and BMI were comparable between groups; 3 women discontinued.

RESULTS

EV + DNG suppressed FSH by -27% (-51% to -3%) (median [95% CI]) vs EE + DNG, -64% (-78 to -51), P = 0.04, but AMH levels decreased similarly by -9% (-18 to -0.1) vs -13% (-28 to 0.2), P = 0.38, respectively. EV + DNG increased SHBG levels by 56% (30% to 82%) and EE + DNG by 385% (313% to 423%), P < 0.001. Total testosterone decreased by 16% (-27% to -5%) in the EV + DNG group but it did not decrease in the EE + DNG group, whereas the FAI decreased by -39% (-54% to -25%) vs -72% (-78% to -67%), P < 0.001. DNG alone did not induce changes in any of these parameters.

CONCLUSION

Compared with EE + DNG, treatment with EV + DNG resulted in milder pituitary downregulation and reduced induction of hepatic SHBG synthesis-potentially carrying more beneficial health effects.

Prospective controlled cohort study on the safety of a monophasic oral contraceptive containing nomegestrol acetate (2.5mg) and 17β-oestradiol (1.5mg) (PRO-E2 study): risk of venous and arterial thromboembolism

OBJECTIVE

To assess and compare the risk of venous thromboembolism (VTE) and arterial thromboembolism (ATE) in NOMAC-E2 users with levonorgestrel-containing combined oral contraceptive (COCLNG) users.

STUDY DESIGN

This large, prospective, observational active surveillance study used a non-inferiority design. New users of NOMAC-E2 and COCLNG were recruited in 12 countries in Australia, Europe, and Latin America. Women were followed up directly and self-reported outcomes of interest were validated via treating physicians. The main outcome of interest was VTE, specifically deep venous thrombosis of the lower extremities (DVT) and pulmonary embolism (PE). Secondary outcomes included all VTE and ATE. Data on confounders were captured and independent blinded adjudication assessed the classification of events. Incidence rates, crude (HRcrude), and adjusted (HRadj) hazard ratios were calculated.

RESULTS

A total of 101,498 women (49,598 NOMAC-E2 users and 51,900 COCLNG users) were enrolled and followed for up to 2 years (144,901 WY of observation). NOMAC-E2 users had a higher mean age (31.0 ± 8.63 years) than COCLNG users (29.3 ± 8.53 years) but other baseline characteristics were similar between the cohorts. The main analysis comparing the risk of DVT of the lower extremities and PE in NOMAC-E2 users versus COCLNG users yielded an HRadj of 0.59 (95% CI, 0.25-1.35) (adjusted for age, BMI, family history of VTE, and current duration of use). The risk of all VTE and ATE was not higher in NOMAC-E2 users compared with COCLNG users.

CONCLUSION(S)

NOMAC-E2 use was not associated with a higher risk of VTE or ATE compared with COCLNG.

Pharmacodynamics of combined estrogen-progestin oral contraceptives 3. Inhibition of ovulation

INTRODUCTION

Following a historical overview, the ovulation-inhibiting effect of various orally administered estrogen-progestin combinations (combined oral contraceptives [COCs]) are examined for their components alone or in the various combined formulations. Special emphasis is given to products containing natural estrogens. Areas covered: Inhibition of ovulation with progestins alone; estrogens alone; various progestins in combination with ethinyl estradiol; various progestins in combination with natural estrogens (estradiol, estradiol valerate, and estetrol). Expert commentary: The original idea to achieve ovulation blockage through the administration of steroid hormones involved the use a progestogen (both progesterone and its synthetic homologous). The ability of a progestin to inhibit ovulation depends on the type of compound and on its dosage and a difference of more than 20-fold in activity exists between compounds utilized today in COCs. Initially, the estrogenic component was present only because it contaminated the first progestin utilized. It was soon found that an estrogen is necessary for proper cycle control. It was also found that the estrogen acts synergistically in inhibiting ovulation. For almost half a century, most COCs contained ethinyl estradiol. Today, also natural estrogens are being employed. Inhibition of ovulation was complete with all early high dose preparations. Decreasing dosage allowed some ovarian activity to occur, occasionally leading to a mature follicle. Even in this situation, defective corpus luteum formation assured contraceptive protection.

Improvement of Low Sexual Desire Due to Antiandrogenic Combined Oral Contraceptives After Switching to an Oral Contraceptive Containing 17β-Estradiol

OBJECTIVES

To investigate the effects of a combined oral contraceptive (COC) containing 17β-estradiol (E2) 1.5 mg and nomegestrol acetate 2.5 mg (NOMAC/E2) on the sexual health of women affected by low sexual desire due to COCs containing ethinylestradiol.

MATERIALS AND METHODS

Eighty-three women (age range 19-32) participated in the study. Sex hormone-binding globulin (SHBG), total testosterone (TT), and free androgen index (FAI) were measured. The Female Sexual Function Index (FSFI) and the Female Sexual Distress Scale (FSDS) questionnaires were used to assess sexual function and distress, respectively. Hormonal levels were measured and questionnaires were administered before the women switched COC NOMAC/E2 usage (baseline) and at the 3-month (first) and 6-month (second) follow-ups.

RESULTS

SHBG reduction (p < 0.001), TT (p < 0.05), and FAI increases (p < 0.001) were observed during the first and second follow-ups with respect to baseline values. Sexual desire increased from baseline to the first and second follow-ups (p < 0.001). At baseline, the total FSFI score was 22 ± 1.5 and the FSDS score was 16.6 ± 1.3, both indicating sexual dysfunction with sexual distress. At the first follow-up, the total FSFI score and the FSDS score increased toward sexual health values, being 28.3 ± 1.6 and 12.1 ± 1.5, respectively (p < 0.001). At the second follow-up, the FSFI score had risen to 30.6 ± 1.3 (p < 0.001) and the FSDS score had dropped to 8.3 ± 1.4 (p < 0.001).

CONCLUSIONS

COCs containing E2 are an innovation that could help women to not suffer from low sexual desire during hypoandrogenic COC usage.

Pipeline for contraceptive development

The high rates of unplanned pregnancy reflect an unmet need for effective contraceptive methods for women, especially for individuals with health risks such as obesity, diabetes, hypertension, and other conditions that may contraindicate use of an estrogen-containing product. Improvements in safety, user convenience, acceptability, and availability of products remain important goals of the contraceptive development program. Another important goal is to minimize the impact of the products on the environment. Development of new methods for male contraception has the potential to address many of these issues of safety for women who have contraindications to effective contraceptive methods but want to protect against pregnancy. It would also address a huge unmet need for men who want to control their fertility. Products under development for men would not introduce ecotoxic hormones into the water system.

Contraceptive options for women with premenstrual dysphoric disorder: current insights and a narrative review

Premenstrual syndrome and its most severe form, premenstrual dysphoric disorder (PMDD), are two well-defined clinical entities that affect a considerable number of women. Progesterone metabolites and certain neurotransmitters, such as gamma-aminobutyric acid and serotonin, are involved in the etiology of this condition. Until recently, the only treatment for women with PMDD was psychoactive drugs, such as selective serotonin reuptake inhibitors. Several years ago, there has been evidence of the beneficial role of combined hormonal contraceptives in controlling PMDD symptoms. Oral combined hormonal contraceptives that contain drospirenone in a 24+4-day regimen are the only drugs that have been approved by US Food and Drug Administration for the treatment of PMDD, but there is scientific evidence that other agents, with other formulations and regimens, could also be effective for the treatment of this condition. However, it remains unclear whether the beneficial effect of combined hormonal contraceptives is associated with the type of estrogen or progestogen used or the treatment regimen.

Inhibition of ovulation by administration of estetrol in combination with drospirenone or levonorgestrel: Results of a phase II dose-finding pilot study

Objectives The aim of the study was to evaluate the efficacy of different dosages of estetrol (E₄) combined with one of two progestins in suppressing the pituitary–ovarian axis and ovulation in healthy premenopausal women.

Methods This was an open, parallel, phase II, dose-finding, pilot study performed in healthy women aged 18 to 35 years with a documented ovulatory cycle before treatment. For three consecutive cycles in a 24/4-day regimen, participants received 5 mg or 10 mg E₄/3 mg drospirenone (DRSP); 5 mg, 10 mg or 20 mg E₄/150 μg levonorgestrel; or 20 μg ethinylestradiol (EE)/3 mg DRSP as comparator. Pituitary–ovarian axis activity and the occurrence of ovulation were evaluated by monitoring follicular size, serum levels of follicle-stimulating hormone, luteinising hormone, estradiol and progesterone during treatment cycles 1 and 3. Endometrial thickness was evaluated throughout the trial, and the return of ovulation was evaluated after the last intake of medication.

Results A total of 109 women were included in the trial. No ovulation occurred in any treatment group. Ovarian activity inhibition seemed proportional to the E₄ dosage: the highest suppression was observed in the 20 mg E₄ group and was very similar to that observed with EE/DRSP. Endometrial thickness was suppressed to the same extent in all groups. Post-treatment ovulation occurred in all participants between 17 and 21 days after the last active treatment. The study combinations were well tolerated and safe.

Conclusions Combined with a progestin, E₄ adequately suppresses ovarian activity, particularly when given at a dosage above 10 mg/day.

Chinese Abstract

摘要

目的 这项研究的目的是评估不同剂量的雌四醇联合两种孕激素中的其中一种对垂体-卵巢轴以及健康的绝经前妇女的排卵方面的抑制疗效。

方法 这是一个在18到35岁的健康女性中进行的开放的、平行的，关于II期药物剂量探索的初步研究，这些女性均有治疗前的排卵周期记录。连续三个周期的24/4-天方案,参与者接受5毫克或10毫克的雌四醇/3毫克屈螺酮;5毫克,10毫克或20毫克的雌四醇/150 μg左炔诺孕酮;或用20 μg炔雌醇/3毫克屈螺酮作比较。在第1和第3个治疗周期，通过监测卵泡的大小,血清促卵泡激素、黄体生成素、雌二醇和孕激素的水平对垂体-卵巢轴的活动和排卵进行评估。对子宫内膜厚度的评估贯穿于整个试验过程中，对排卵抑制的评估在用完药物之后。

结果 总共有109名妇女参与试验。任何一个治疗组都没有出现排卵。对卵巢活动的抑制似乎与雌四醇的剂量成正比：最严重的抑制出现在20毫克的雌四醇组，与在炔雌醇/屈螺酮组观察到的情况非常相似。所有组的子宫内膜厚度的抑制程度是相同的。在最后一次积极治疗后的第17到21天之间，所有参与者均出现了治疗后的排卵。所有的试验组合均有良好的耐受性和安全性。

结论 雌四醇联合一种雌激素能够充分的抑制卵巢活动，尤其是当雌四醇的剂量大于10毫克/天的时候。

关键词

雌四醇；雌激素；口服避孕药；排卵抑制；孕激素

An update on new orally administered contraceptives for women

INTRODUCTION

The focus in contraception is shifting from oral contraceptives to more effective methods, such as implants and intrauterine devices. Generics are favored by third-party payors. As a result, potentially exciting developments in branded pills to increase safety or to reduce side effects may have gone unnoticed.

AREAS COVERED

This article reviews the features of each of the four new oral contraceptives that have been introduced in the United States and/or Europe in the last few years. The motivation for the development of each product is outlined as is its efficacy, safety, tolerability and the noncontraceptive applications that have been explored are described.

EXPERT OPINION

The hypothesis that using estradiol in place of ethinyl estradiol would reduce the risk of venous thromboembolism is still to be proven. However, the stronger progestogens used in these formulations may offer other tangible benefits for selected women. The new products for extended cycle pill use may have less impact. The flexible regimen can be adopted using any pill, but the approved product does provide convenience to patients. Cost will continue to be the determining factor in the acceptance of these new products, unless substantial health benefits can be conclusively proven.

Nomegestrol acetate/17-beta estradiol: a review of efficacy, safety, and patient acceptability

Nomegestrol acetate (NOMAC) 2.5 mg with 17-beta estradiol (E2) 1.5 mg is a new combined oral contraceptive (COC) formulation and is the first monophasic E2 pill to be marketed, having been licensed for use in Europe in 2011. It is available to be taken daily in a regimen of 24 active pills followed by four placebo pills. NOMAC is a highly selective 19-nor progestogen derivative with specific binding to progesterone receptors, anti-estrogenic activity and no androgenic, mineralocorticoid nor glucocorticoid effects. E2 is an estrogen that is identical to endogenous estrogen. While it has been in use for only a short period of time, current evidence suggests that NOMAC/E2 is just as effective, safe, and acceptable as existing COC preparations. Two large Phase III trials conducted in the Americas and across Europe, Australia, and Asia showed lower cumulative pregnancy rates in the NOMAC/E2 groups compared to the drospirenone (DRSP) 3 mg in combination with ethinyl estradiol (EE) 30 µg (DRSP/EE) groups but this difference was not statistically significant. NOMAC/E2 exhibits a good safety profile and has less effects on cardiovascular risk, hemostatic, metabolic, and endocrine factors in comparison to COCs containing EE in combination with levonorgestrel (LNG) or DRSP. NOMAC/E2 has also been found to cause less breast cell proliferation when compared to E2 alone and has some anti-proliferative effect on human breast cancer cells. NOMAC/E2 is considered acceptable as its compliance, continuation rates, and bleeding patterns were similar to COCs containing DRSP/EE and LNG 150 µg combined with EE 30 µg or LNG 100 µg combined with EE 20 µg (LNG/EE). However, discontinuation was found to be slightly higher in the NOMAC/E2 groups in the two large Phase III trials comparing NOMAC/E2 use with DRSP/EE. As the scientific literature has limited information on NOMAC/E2, further experience with NOMAC/E2 is required.

Comparative analysis of the effects of nomegestrol acetate/17 β-estradiol and drospirenone/ethinylestradiol on premenstrual and menstrual symptoms and dysmenorrhea

OBJECTIVES

To compare premenstrual and menstrual symptoms in healthy women using nomegestrol acetate/17β-estradiol (NOMAC/E2) and drospirenone/ethinylestradiol (DRSP/EE) via the Moos Menstrual Distress Questionnaire Form C (MDQ-C).

METHODS

Women completed the MDQ-C at baseline and after completion of cycles 1, 3, 6 and 13, for the premenstrual (four days before most recent flow) and menstrual (most recent flow) phases in two randomized controlled trials. Treatment effects of NOMAC/E2 and DRSP/EE on the t-scores of eight MDQ-C symptom domains from 3522 women were examined, and the effects of both treatments on the score for cramps from 1779 women with moderate to severe cramps at baseline. Longitudinal data analysis methods were applied in both analyses.

RESULTS

NOMAC/E2 users experienced a significant improvement in Pain, Water Retention, Negative Affect, Impaired Concentration and Behaviour Change domain scores in the menstrual phase compared with DRSP/EE users (p < 0.001 for all comparisons). However, Arousal (emotional and mental) scores worsened with NOMAC/E2 but not with DRSP/EE. Women with moderate to severe cramps experienced an improvement in the cramps score with NOMAC/E2 and DRSP/EE.

CONCLUSIONS

NOMAC/E2 was effective in reducing most premenstrual and menstrual symptoms, and was associated with significantly greater improvements in many MDQ-C domain scores compared with DRSP/EE. ( ClinicalTrials.gov: NCT00413062 and NCT00511199).

Toward a new concept of "natural balance" in oral estroprogestin contraception

The Pill has undergone many changes since its first appearance some 50 years ago. Key developments included the reduction of ethinylestradiol doses and the synthesis of new progestins in order to increase safety, compliance and efficiency. Low-dose combined oral contraceptives (COCs) are currently the preferred option for millions of women. Due to this widespread use, it has been argued that the safety of COCs should be even better, raising the threshold for excellence. Yet in spite of major improvements, there is still an associated risk of venous thromboembolism (VTE). The next step in COCs' evolution should take total estrogenicity and hepatic estro-androgenic balance into account. The focus on the estrogen component--which has not changed in 50 years--has yielded a new class of natural estrogen pills. Following the introduction of a first quadriphasic pill, a monophasic estradiol pill based on the concept of "natural balance" was subsequently made available. These recent achievements could represent a step forward in the evolution of COCs and pave the way for better safety.

The effect of combined oral contraception on testosterone levels in healthy women: a systematic review and meta-analysis

BACKGROUND; Combined oral contraceptives (COCs) reduce levels of androgen, especially testosterone (T), by inhibiting ovarian and adrenal androgen synthesis and by increasing levels of sex hormone-binding globulin (SHBG). Although this suppressive effect has been investigated by numerous studies over many years, to our knowledge no systematic review concerning this issue had been performed. This systematic review and meta-analysis was performed to evaluate the effect of COCs on concentrations of total T, free T and SHBG in healthy women and to evaluate differences between the various types of COCs (e.g. estrogen dose, type of progestin) and the assays used to assess total T and free T.

METHODS

A review of the literature was performed using database searches (MEDLINE, EMBASE and the Cochrane Central Register of Clinical Trials) and all publications (from inception date until July 2012) investigating the effect of COCs on androgen levels in healthy women were considered eligible for selection. Three reviewers were involved in study selection, data extraction and critical appraisal. For the meta-analysis, data on total T, free T and SHBG were extracted and combined using random effects analysis. Additional subgroup analyses were performed to evaluate differences between the various types of COCs (e.g. estrogen dose, type of progestin) and the assays used to assess total T or free T.

RESULTS

A total of 151 records were identified by systematic review and 42 studies with a total of 1495 healthy young women (age range: 18-40 years) were included in the meta-analysis. All included studies were experimental studies and 21 were non-comparative. Pooling of the results derived from all the included papers showed that total T levels significantly decreased during COC use [mean difference (MD) (95% confidence interval, CI) -0.49 nmol/l (-0.55, -0.42); P < 0.001]. Significantly lower levels of free T were also found [relative change (95% CI) 0.39 (0.35, 0.43); P < 0.001], with a mean decrease of 61%. On the contrary, SHBG concentrations significantly increased during all types of COC use [MD (95% CI) 99.08 nmol/l (86.43, 111.73); P < 0.001]. Subgroup analyses revealed that COCs containing 20-25 µg EE had similar effects on total and free T compared with COCs with 30-35 µg EE. In addition, suppressive effects on T levels were not different when comparing different types of progestins. However, subgroup analyses for the estrogen dose and the progestin type in relation to changes in SHBG levels did show significant differences: COCs containing second generation progestins and/or the lower estrogen doses (20-25 µg EE) were found to have less impact on SHBG concentrations.

CONCLUSIONS

The current literature review and meta-analysis demonstrates that COCs decrease circulating levels of total T and free T and increase SBHG concentrations. Due to the SHBG increase, free T levels decrease twice as much as total T. The estrogen dose and progestin type of the COC do not influence the decline of total and free T, but both affect SHBG. The clinical implications of suppressed androgen levels during COC use remain to be elucidated.

The pharmacokinetics and pharmacodynamics of dehydroepiandrosterone during use of an ethinylestradiol- and drospirenone-containing oral contraceptive

BACKGROUND

Combined oral contraceptives (COCs) reduce the levels of ovarian and adrenal androgens. Co-administration of dehydroepiandrosterone (DHEA) may normalise androgen levels during COC use.

OBJECTIVE

To investigate the effect of the addition of DHEA to a COC on the pharmacokinetics (PK) and pharmacodynamics (PD) of DHEA and its sulphate (DHEA-S), and on levels of total and free testosterone (T).

METHODS

In a prospective, randomised, double-blind, placebo-controlled, cross-over study involving 21 female volunteers, the PK and PD of DHEA and DHEA-S were investigated during the use of one cycle of a COC containing 30 μg ethinylestradiol (EE) and 3 mg drospirenone (DRSP) with and without daily co-administration of 50 mg DHEA.

RESULTS

Treatment during one cycle with a COC containing EE and DRSP reduces the exposure to DHEA and DHEA-S by at least 20%. This loss of adrenal androgens can be fully compensated by daily oral co-administration of 50 mg DHEA. With DHEA co-administration total T levels rise significantly (1.44 nmol/L with DHEA vs. 0.82 nmol/L with placebo; p < 0.001). Free T levels decrease significantly with both DHEA and placebo treatment, but significantly less during co-administration of DHEA (6.34 pmol/L with DHEA vs. 3.96 pmol/L with placebo; p < 0.001).

CONCLUSION

By adding DHEA to a COC the loss of adrenal and ovarian androgens can be restored.

Nomegestrol acetate-17b-estradiol for oral contraception

Oral contraceptives remain a popular method of contraception over 50 years after their introduction. While safe and effective for many women, the failure rate of oral contraception is about 8%. Concerns about the risk of venous thromboembolism continue to drive the search for the safest oral contraceptive formulations. The oral contraceptive NOMAC-E2 contains nomegestrol acetate (NOMAC) 2.5 mg + 17b-estradiol (E2) 1.5 mg. The approved dosing regimen is 24 days of active hormone, followed by a 4-day hormone-free interval. NOMAC is a progestin derived from testosterone, which has high bioavailability, rapid absorption, and a long half-life. Estradiol, though it has a lower bioavailability, has been successfully combined with NOMAC in a monophasic oral contraceptive. Two recently published randomized controlled trials demonstrate that NOMAC-E2 is an effective contraceptive, with a Pearl Index less than one pregnancy per 100 woman-years. The bleeding pattern on NOMAC-E2 is characterized by fewer bleeding/spotting days, shorter withdrawal bleeds, and a higher incidence of amenorrhea than the comparator oral contraceptive containing drospirenone and ethinyl estradiol. The adverse event profile appears to be acceptable. Few severe adverse events were reported in the randomized controlled trials. The most common adverse events were irregular bleeding, acne, and weight gain. Preliminary studies suggest that NOMAC-E2 does not seem to have negative effects on hemostatic and metabolic parameters. While no one oral contraceptive formulation is likely to be the optimum choice for all women, NOMAC-E2 is a formulation with effectiveness comparable with that of other oral contraceptives, and a reassuring safety profile.

The bioequivalence of the contraceptive steroids ethinylestradiol and drospirenone is not affected by co-administration of dehydroepiandrosterone

OBJECTIVES

To study the effect of co-administration of 50 mg dehydroepiandrosterone (DHEA) on the bioequivalence of ethinylestradiol (EE) and drospirenone (DRSP) in women who were using a combined oral contraceptive (COC) containing 30 μg EE and 3 mg DRSP, and to estimate whether the addition of DHEA to this COC affects the serum levels and the bioequivalence of the synthetic contraceptive steroids.

METHODS

This was a randomised, double-blind, two-period crossover study. Participants received two EE/DRSP COC treatment cycles in random order, one with and one without daily 50 mg DHEA , separated by a 28-day wash-out cycle during which the subjects used an EE/levonorgestrel (LNG) COC without DHEA. Serum levels of EE and DRSP were measured according to a sampling scheme allowing pharmacokinetic evaluations.

RESULTS

Addition of DHEA to an EE/DRSP COC had no effect on serum levels of EE and DRSP. The COC regimens with and without DHEA were bioequivalent. Oestradiol levels were equally suppressed during pill intake, whether with placebo or DHEA.

CONCLUSION

Adding DHEA to a COC containing EE and DRSP does not affect the pharmacokinetic properties of EE and DRSP. Therefore, it will most likely not affect its contraceptive efficacy.

Preclinical pharmacological profile of nomegestrol acetate, a synthetic 19-nor-progesterone derivative

BACKGROUND

Nomegestrol acetate (NOMAC), a synthetic progestogen derived from 19-nor-progesterone, recently completed clinical trials for use with 17beta-estradiol in a new monophasic combined oral contraceptive. In this review, published as well as previously unpublished preclinical studies that detail the effects of NOMAC on estrogenic, progestogenic, and androgenic systems, as well as mineralocorticoid, glucocorticoid, bone, and metabolic indices are described.

METHODS

In vitro assays to determine NOMAC structure-activity relationships used tissue derived from rat uteri. Transactivation profiles were performed using Chinese hamster ovary (CHO) cells transfected with cDNAs encoding human steroid receptors. Estrogenic and anti-estrogenic activities were monitored in vivo in rats as well as in vitro in human breast cancer cells. Standard in vivo techniques were used in rats to determine progestational activity; antigonadotropic, androgenic, mineralocorticoid, and glucocorticoid activities; as well as effects on bone and other metabolic indices. Ovulation inhibition was monitored in rats and primates. NOMAC's effects on cardiovascular systems were determined in dogs and primates.

RESULTS

NOMAC was without significant agonistic or antagonistic activity for estrogen receptor alpha or beta in vitro, and inhibited ovulation in rats and monkeys (2.5 mg/kg and 1 mg/kg, respectively). NOMAC lacked androgenic, antimineralocorticoid, glucocorticoid, and metabolic activity and exhibited moderate anti-androgenic activity in rats. NOMAC did not affect bone mineral density (BMD) in rats or hemodynamic and electrophysiologic parameters in dogs and primates.

CONCLUSIONS

NOMAC is a selective progestogen structurally similar to progesterone that has modest anti-androgenic activity and does not affect lipid or carbohydrate metabolism, BMD, or many cardiovascular parameters in selected animal models.

Pharmacokinetic profile of nomegestrol acetate and 17β-estradiol after multiple and single dosing in healthy women

BACKGROUND

The pharmacokinetics of the monophasic oral contraceptive nomegestrol acetate (NOMAC) plus 17β-estradiol (E(2)) were investigated after a single dose and multiple dosing.

STUDY DESIGN

NOMAC/E2 (2.5 mg/1.5 mg) was administered daily to healthy women (18-50 years, n=23) for 24 days; blood samples for pharmacokinetic analysis were obtained on Day 24 and again, after a 10-day pill-free interval, on Day 35 after a single dose.

RESULTS

NOMAC reached steady state after 5 days with mean ±standard deviation (SD) trough NOMAC concentration (C(av)) of 4.4±1.4 ng/mL. On Day 24, mean±SD peak NOMAC concentration (Cmax, 12.3±3.5 ng/mL) was reached in mean 1.5 h (t(max)); the mean±SD elimination half-life (t(½)) was 45.9±15.3 h. After a single dose, NOMAC mean±SD C(max) was 7.2±2.0 ng/mL and mean±SD t(½) was 41.9±16.2 h. On Day 24, E2 mean±SD C(av) was 50.3±25.7 pg/mL; mean±SD Cmax was 86.0±51.3 pg/mL. After a single dose, mean±SD E2 Cmax was 253±179 pg/mL.

CONCLUSIONS

These data demonstrate that NOMAC/E2 has a pharmacokinetic profile consistent with once-daily dosing.

An overview of the development of combined oral contraceptives containing estradiol: focus on estradiol valerate/dienogest

Natural estrogens such as estradiol (E(2)) or its valerate ester (E(2)V) offer an alternative to ethinyl estradiol (EE). E(2)-containing combined oral contraceptives (COCs) have demonstrated sufficient ovulation inhibition and acceptable contraceptive efficacy. However, earlier formulations were generally associated with unacceptable bleeding profiles. Two E(2)V-containing preparations have been approved to date for contraceptive use: E(2)V/cyproterone acetate (CPA) (Femilar(®); only approved in Finland and only in women >40 years or women aged 35-40 years in whom a COC containing EE is not appropriate) and E(2)V/dienogest (DNG; Qlaira(®)/Natazia(®)). The objective of the current review is to provide an overview of the development of COCs containing natural estrogen, highlighting past issues and challenges faced by earlier formulations, as well as the current status and future directions. The majority of information to date pertains to the development of E(2)V/DNG.

Efficacy and tolerability of a monophasic combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol in a 24/4 regimen, in comparison to an oral contraceptive containing ethinylestradiol and drospirenone in a 21/7 regimen

OBJECTIVES

The primary objective was to assess the efficacy, cycle control and tolerability of a monophasic combined oral contraceptive (COC) containing nomegestrol acetate (NOMAC) and 17β-oestradiol (E2). Effects on acne were evaluated as a secondary objective. Results were compared to those of a COC containing drospirenone (DRSP) and ethinylestradiol (EE).

METHODS

Women (aged 18-50 years) were randomised to receive NOMAC/E2 (2.5 mg/1.5 mg) in a 24/4-day regimen (n=1591) or DRSP/EE (3 mg/30 μg) in a 21/7-day regimen (n=535) for 13 cycles.

RESULTS

Estimated Pearl Indices for NOMAC/E2 and DRSP/EE were 0.38 and 0.81 in women aged≤35 years and 0.31 and 0.66 for all women (18-50 years), respectively. Scheduled withdrawal bleedings were shorter and lighter among users of NOMAC/E2 and were sometimes absent altogether. Intracyclic bleeding/spotting was infrequent in both groups, and decreased over time. Type and frequency of adverse events were similar to those typically reported for COCs.

CONCLUSIONS

These data show that NOMAC/E2 provides high contraceptive efficacy with acceptable cycle control as well as an overall adverse event profile similar to that of DRSP/EE.

Effects of a monophasic combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol compared with one containing levonorgestrel and ethinylestradiol on haemostasis, lipids and carbohydrate metabolism

OBJECTIVES

To compare the effects of a combined oral contraceptive (COC) containing nomegestrol acetate and 17β-oestradiol (NOMAC/E2) on haemostasis, lipids, carbohydrate metabolism, C-reactive protein (CRP) and sex hormone-binding globulin (SHBG) with those of a COC containing levonorgestrel and ethinylestradiol (LNG/EE).

METHODS

In a randomised, open-label study, 121 healthy women, 18-50 years of age, were randomly assigned to receive NOMAC/E2 (2.5 mg/1.5 mg) in a 24/4-day regimen (n=60) or LNG/EE (150 μg/30 μg) in a 21/7-day regimen (n=61) for six cycles. The primary outcome was the change from baseline to cycle 6 for all indices.

RESULTS

All parameters were similar at baseline between the two groups. Over six cycles, NOMAC/E2 had less effect on most haemostatic indices than LNG/EE. Lipids were essentially unchanged with NOMAC/E2, whereas with LNG/EE high-density lipoprotein cholesterol decreased and low-density lipoprotein cholesterol and triglycerides slightly increased. NOMAC/E2 induced negligible changes in glucose and insulin parameters, in contrast to LNG/EE. A much smaller increase in CRP was observed with NOMAC/E2 than with LNG/EE. NOMAC/E2 was associated with a greater increase in SHBG.

CONCLUSIONS

The monophasic COC NOMAC/E2 had less influence on haemostasis, lipids and carbohydrate metabolism than the COC LNG/EE.

The state of hormonal contraception today: benefits and risks of hormonal contraceptives: combined estrogen and progestin contraceptives

Discussion of effective birth control methods can be a challenging process for clinicians because the adoption and consistent use of contraception may be influenced by patients' fears, myths, and misperceptions. Over the years, new progestins have been included in combination contraceptives or are used alone to provide effective contraception as well as to decrease androgenic side effects and ameliorate the symptoms of premenstrual dysphoric disorder. Alternative delivery systems and regimens have also been introduced to improve tolerability and continuance and convenience of use. This is a review of estrogen and progestin combinations and their effects.

The future of contraception: innovations in contraceptive agents: tomorrow's hormonal contraceptive agents and their clinical implications

Currently available contraceptive methods have not eliminated the burden of unintended pregnancy. Future progress will require technological advancements, leading to the development of novel and highly effective birth control strategies that will be acceptable to the general population. Included are highlights of some of the ongoing research, demonstrating the development of methods with the potential to be highly effective, widely accepted, easy to use, and more cost-effective, with fewer side effects, than currently available options.

Effects of a monophasic combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol in comparison to one containing levonorgestrel and ethinylestradiol on markers of endocrine function

Objectives

To compare the effects of two monophasic combined oral contraceptives, containing either nomegestrol acetate/17β-oestradiol (NOMAC/E2) or levonorgestrel/ ethinylestradiol (LNG/EE) on endocrine function, androgens, and sex hormone-binding globulin (SHBG).

Methods

Randomised, open-label, multi-centre trial involving 121 healthy women, aged 18-50 years old. Participants received NOMAC/E2 (2.5 mg/1.5 mg) in a 24/4-day regimen (n = 60) or LNG/EE (150 μg/30 μg) in a 21/7-day regimen (n = 61) for six cycles. The primary outcome was the change from baseline to cycle 6 in markers of adrenal and thyroid function, androgens, and SHBG.

Results

Total cortisol, corticosteroid-binding globulin (CBG), and thyroxine-binding globulin (TBG) increased from baseline in both groups, with significantly greater increases in the LNG/EE group. No relevant changes from baseline or differences between the groups were observed for thyroid-stimulating hormone (TSH) and free thyroxine (T₄). Androgens and androgen precursors decreased from baseline in both groups, with significantly greater decreases in the LNG/EE group (except for free testosterone). A greater increase in SHBG was observed with NOMAC/E2 than with LNG/EE.

Conclusions

NOMAC/E2 has significantly less influence on markers of adrenal and thyroid function and androgens than LNG/EE. The clinical relevance of these findings requires further study.

Nomegestrol acetate, a novel progestogen for oral contraception

Nomegestrol acetate (NOMAC) is a potent, highly selective progestogen, which is structurally similar to 19-norprogesterone and characterized as a full agonist at the progesterone receptor, with no or minimal binding to other steroid receptors, including the androgen and glucocorticoid receptors. In animal models, NOMAC demonstrated moderate antiandrogenic activity and strong antiestrogenic activity. In clinical studies, the progestogen was associated with effective suppression of gonadotropic activity and ovulation in premenopausal women, and a neutral impact on hemostasis, lipids, and carbohydrate metabolism. In normal and cancerous human breast tissue, NOMAC has shown favorable effects on estrogen metabolism, and in human breast cancer cell lines in vitro, it does not stimulate cell proliferation. The pharmacologic profile of NOMAC suggested that it would be well suited for combination with a physiologic estrogen in a combined oral contraceptive (COC), with the aim of achieving effective contraception with good cycle control and a favorable safety profile. A monophasic COC containing NOMAC 2.5mg and 17β-estradiol (E2) 1.5mg, administered in a 24/4-day regimen, is currently under clinical investigation. In a phase III study, NOMAC/E2 provided consistent and robust ovulation inhibition, with contraceptive effects that compared favorably with those of drospirenone 3mg/ethinyl estradiol (EE) 30 μg. Investigators for a second phase III study reported less overall impact with NOMAC/E2 on hemostatic, lipid, inflammatory, and carbohydrate metabolism parameters than with levonorgestrel 150 μg/EE 30 μg. These clinical findings are promising; however, full publication of results from the pivotal phase III trials of NOMAC/E2 is pending.

Comparison of a 24-day and a 21-day pill regimen for the novel combined oral contraceptive, nomegestrol acetate and 17β-estradiol (NOMAC/E2): a double-blind, randomized study

BACKGROUND Nomegestrol acetate/17β-estradiol (NOMAC/E(2)) is a new monophasic oral contraceptive combining NOMAC (2.5 mg), a highly selective progesterone-derived progestogen, with E(2) (1.5 mg), which is structurally identical to endogenous estrogen. The objective of this study was to compare the effects on ovarian activity of two different NOMAC/E(2) regimens. METHODS This was a double-blind, randomized study. Healthy, premenopausal women (aged 18-38 years, previous menstrual cycle length 28 ± 7 days) were randomized by computer-generated code to once-daily NOMAC/E(2) for three consecutive 28-day cycles: either 24 days with a 4-day placebo interval (n = 40) or 21 days with a 7-day placebo interval (n = 37) per cycle. Follicular growth (primary outcome measure), plasma hormone profiles and bleeding patterns were assessed. RESULTS There was no evidence of ovulation during treatment with either NOMAC/E(2) regimen. The largest follicle diameter was significantly smaller in the 24-day group than in the 21-day group [mean (SD) mm in cycle 2: 9.0 (3.0) versus 11.3 (5.3) (P = 0.02); in cycle 3: 9.2 (3.0) versus 11.5 (6.0) (P = 0.04)]. Mean FSH plasma levels were significantly lower in the 24-day versus the 21-day group on Day 24 of cycles 1 and 2. Withdrawal bleeding duration was significantly shorter in the 24-day than in the 21-day group [mean (SD) days after cycle 1: 3.5 (1.3) versus 5.0 (2.6) (P = 0.002); after cycle 2: 3.9 (1.6) versus 4.8 (1.7) (P = 0.03)]. CONCLUSIONS The 24-day NOMAC/E(2) regimen was associated with greater inhibition of follicular growth and shorter duration of withdrawal bleeding than the 21-day regimen, suggesting the shorter pill-free interval results in a greater margin of contraceptive efficacy and tolerability, and fewer withdrawal symptoms.