Factors associated with withdrawal bleeding after administration of oral dydrogesterone or medroxyprogesterone acetate in women with secondary amenorrhea

A safety evaluation of current medications for adult women with the polycystic ovarian syndrome not pursuing pregnancy

INTRODUCTION

The polycystic ovary syndrome (PCOS) is a very prevalent disorder in premenopausal women. Cardiovascular risk factors cluster in these patients, raising concern about the safety of the drugs commonly used to ameliorate symptoms of androgen excess in in this population at risk of cardiovascular morbidity.

AREAS COVERED

This review summarizes the clinical efficacy and safety profiles of drugs commonly used for the management of hyperandrogenic symptoms and endometrial protection in adult women with PCOS who do not seek pregnancy.

EXPERT OPINION

Antiandrogenic drugs usually used in adult women with PCOS carry a low risk of severe side effects. In spite of the cardiovascular risk profile of women with PCOS, and that individualized risk assessment is of paramount importance, there is no solid evidence supporting that the use of combined oral contraceptives in these women increases the risk of cardiovascular or thromboembolic events compared with the general population. However, virtually all these drugs are used in an off-label fashion. Large, high-quality studies addressing the long-term safety of pharmacological treatments in women with PCOS are definitely needed.

The steroid hormone dydrogesterone inhibits myometrial contraction independently of the progesterone/progesterone receptor pathway

AIMS

In this study, we aimed to investigate the direct effects of steroid hormones on pregnant myometrial contraction.

MAIN METHODS

The effect of steroids on oxytocin-induced contraction was examined in vitro using pregnant rat or human myometrium. Subsequently, we evaluated whether RU486, a potent progesterone antagonist, influenced the effects of progestin on myometrial contraction. Additionally, we evaluated the effects of progestin on high-concentration KCl-induced contraction caused by voltage-dependent calcium channels in order to investigate the mechanisms involved in this process.

KEY FINDINGS

Of the natural steroids examined, 17β-estradiol, progesterone, testosterone, cortisol, and aldosterone did not influence oxytocin-induced contraction at concentrations <10^-6 M. Of the tested progestins, medroxyprogesterone acetate, norethisterone, chlormadinone acetate, levonorgesterol, 17α-hydroxyprogesterone capronate, and dienogest had no effect on contraction at <10^-6 M. However, dydrogesterone showed rapid and direct inhibition of contraction at 10^-6 M, and this inhibitory effect was dependent on dose and time. RU486 did not block the inhibitory effects of dydrogesterone on contraction. High-concentration KCl-induced contraction was also inhibited by dydrogesterone, and the inhibitory effects of dydrogesterone were observed at concentrations as low as 10^-7 M. Additionally, oxytocin-induced contraction in pregnant human myometrium was inhibited by 10^-6 M dydrogesterone.

SIGNIFICANCE

These results suggested that the rapid and direct effects of dydrogesterone on myometrial contraction were caused by a nongenomic pathway and that the progesterone receptor was not required for dydrogesterone action. Additionally, the mechanism of dydrogesterone action may involve voltage-dependent calcium channels.

Rapid Quantification of Medroxyprogesterone Acetate (MPA) in Human Plasma by LC-MS/MS

BACKGROUND

Medroxyprogesterone acetate (MPA) is a common contraceptive agent taken both orally and as a subcutaneous or intramuscular injection. Current LC-MS/MS methods for MPA quantification require large sample volumes and low-throughput analytical run times. Therefore, there are opportunities to improve upon existing methods for MPA quantification.

METHODS

MPA was extracted from 600 μL plasma, evaporated to dryness, and the reconstituted solution was injected onto a Waters Acquity liquid chromatography (LC) system via an Agilent Zorbax Eclipse-Plus C18 2.1 × 50 mm (5.0 μm) column. MPA and its internal standard were monitored on a QTRAP® 5500 mass analyzer operated in positive ionization mode. The method was validated according to the Food and Drug Administration Bioanalytical Method Validation guidelines.

RESULTS

The analytical measuring range of the assay was 200-10 000 pg/mL. QC samples prepared at the lower limit of quantification (LLOQ; 200 pg/mL) and low (600 pg/mL), mid (1750 pg/mL), and high (8500 pg/mL) levels showed interassay precision and accuracy ≤15.2% and ≤±9.6%, respectively. Stability-challenged samples yielded ≤15% from freshly prepared samples. Dilutional and matrix effects studies were also acceptable. The assay was also assessed in participants prescribed depot medroxyprogesterone acetate; observed concentrations were within the dynamic range of the assay.

CONCLUSIONS

An LC-MS/MS method for the quantification of MPA in plasma has been developed and validated. The described method is sufficiently sensitive and robust to quantify MPA in plasma and meets the criteria to support clinical trials.

Progestational effects of dydrogesterone in vitro, in vivo and on the human endometrium

Dydrogesterone has a molecular structure closely related to that of natural progesterone, but it has enhanced oral availability compared with progesterone. The hormonal profile and the progestational potency of dydrogesterone has been determined in vitro, in vivo and in humans, in combination with estrogens or without. It showed varying affinity for progesterone-binding proteins in uterine tissue in vitro, depending on the species. It exerted a clear progestational response in the rabbit in vivo, although the potency was influenced somewhat by the route of administration. When used in hormone replacement therapy, 10mg dydrogesterone given sequentially provides adequate protection against endometrial hyperplasia in postmenopausal women using 2mg estradiol. Similarly, a dydrogesterone dose of 5mg also protects the endometrium when continuously combined with 1mg estradiol. Dydrogesterone also has beneficial effects in women with amenorrhea/oligomenorrhea, dysfunctional uterine bleeding and irregular cycles. In conclusion, having a similar profile to progesterone but with better oral availability, dydrogesterone has been used successfully to treat disorders related to absolute or relative progesterone deficiency.

Cyclical dydrogesterone in secondary amenorrhea: results of a double-blind, placebo-controlled, randomized study

Secondary amenorrhea in women with normal estrogen levels increases the risk of endometrial carcinoma. Cyclical dydrogesterone induces regular withdrawal bleeding and effectively protects the endometrium of postmenopausal women receiving estrogens. In order to assess the efficacy of dydrogesterone in inducing regular withdrawal bleeds in premenopausal women with secondary amenorrhea or oligomenorrhea and normal estrogen levels, a double-blind, randomized, placebo-controlled, multicenter study was conducted in 104 women using cyclical dydrogesterone as is used for estrogen replacement therapy. Treatment consisted of dydrogesterone (10 mg/day on days 1-14 followed by placebo on days 15-28 of each cycle) given for six cycles of 28 days. The control group received placebo throughout the six cycles. Bleeding was documented by the patient on diary cards. The number of women with withdrawal bleeding during the first cycle was twice as high in the dydrogesterone group as in the placebo group (65.4% vs. 30.8%; p = 0.0004). Superiority of dydrogesterone was also observed for regularity of bleeding over the six cycles (p < 0.0001), although endometrial thickness after six cycles did not differ between the groups. In conclusion, dydrogesterone is significantly superior to placebo in inducing withdrawal bleeding, and maintaining regular bleeding, in women with secondary amenorrhea and normal estrogen levels.

Current state of hormone replacement therapy: the case for using trimegestone

Estrogen deficiency has a negative impact on the quality of life of postmenopausal women and is associated with vasomotor symptoms, insomnia and emotional lability. Other manifestations of estrogen deficiency include dry skin, dry vagina and dyspareunia, in addition to bone loss. Estrogen replacement effectively reverses these changes. The only indication for the administration of a progestogen is to protect the postmenopausal uterus against the potential development of endometrial hyperplasia and carcinoma.

A Review of Drospirenone for Safety and Tolerability and Effects on Endometrial Safety and Lipid Parameters Contrasted with Medroxyprogesterone Acetate, Levonorgestrel, and Micronized Progesterone

BACKGROUND

Drospirenone, a novel synthetic progestin, possesses characteristics more like natural progesterone than other synthetic progestins, such as medroxyprogesterone acetate and levonorgestrel. The antiandrogenic and antimineralocorticoid properties of drospirenone may, in the context of menopausal management, provide potential novel benefits in its effect on lipids and blood pressure while reducing the occurrence of water retention, acne vulgaris, and hirsutism.

METHODS

This review compares safety and tolerability data from clinical trials of drospirenone, medroxyprogesterone acetate, levonorgestrel, and micronized progesterone.

RESULTS

Results suggest that drospirenone possesses a generally well-accepted side effect profile and resembles comparator oral progestogens in conferring endometrial protection with no significant effect on weight. One study indicates that drospirenone may have a benign effect on lipid parameters, having been seen to significantly lower total cholesterol and lowdensity lipoprotein levels while maintaining high-density lipoprotein and triglyceride levels. Drospirenone also differs from the other progestogens in lowering blood pressure levels in hypertensive patients while having a mild blood pressure-lowering effect on nonhypertensive patients.

CONCLUSIONS

Among pharmacological options for menopause management, drospirenone may provide certain advantages over other progestogens in its effect on risk factors for cardiovascular disease and, thus, constitutes a useful addition to the menopausal armamentarium.

Use of dydrogesterone as a progestogen for oral contraception

Dydrogesterone is a potent orally active progestogen that has been used in clinical practice for over 40 years. Chemically, it belongs to the class of retrosteroids. Dydrogesterone is closely related to endogenous progesterone. It differs from most other synthetic progestogens in that it has no estrogenic, androgenic, glucocorticoid, or anabolic effects. The use of progestogens such as dydrogesterone is indicated in all cases of relative or absolute endogenous progesterone deficiency. Nowadays, dydrogesterone is mainly used in hormone replacement therapy (HRT). The present pilot study explored whether dydrogesterone could also be used as a progestogen for oral contraception. Given its highly favorable safety and tolerability profile, it would provide improvement over existing progestogens currently used in oral contraceptives (OCs). The results of this study indicate that dydrogesterone might indeed be a suitable candidate for use in oral contraception. This concept is currently being investigated further in two open-label phase II trials.