Elagolix: First Global Approval

Development and Application of a Physiologically Based Pharmacokinetic Model for Elagolix in the Adult and Adolescent Population

INTRODUCTION

Endometriosis, a common and distressing gynecological condition, affects fertility and causes pain, is often managed with medications such as Elagolix. The present study aimed to construct a physiologically based pharmacokinetic (PBPK) model for elagolix to predict its pharmacokinetics in different populations, including those with special conditions, to enhance treatment strategies for endometriosis.

METHODS

The PBPK model was optimized using observational data based on the oral administration of elagolix in a healthy Chinese population under fasting conditions. Model accuracy was further verified by comparing the predicted postprandial elagolix concentration data for healthy Chinese individuals with observed data and by comparing these values with the predicted values in a US population model with renal injury or following multiple-dose administration.

RESULTS

Elagolix pharmacokinetic (PK) profiles in the Chinese and American populations exhibited no differences that were attributable to ethnicity. The model predicted in vivo PK in adolescents aged 14-18 years, revealing no clinically significant differences in the effects of elagolix between adolescents and adults. In addition, no predicted PK differences in individuals with overweight were observed. However, notable variations emerged in those classified as obesity class 2 and above compared to healthy individuals.

CONCLUSION

Our study presents a novel PBPK model for elagolix in healthy Chinese women, addressing a clinical data gap for its use in adolescents and obese patients. By validating the model with real-world factors, including diet and renal impairment, we provide initial pharmacokinetic predictions for these populations, contributing to a more informed clinical approach.

Medical Management of Endometriosis in Adolescent and Young Adult Women: A Review of 91 Cases of Biopsy-Confirmed Endometriosis

OBJECTIVES

To characterise contemporary trends in the hormonal management of endometriosis in adolescent and young adult patients with biopsy-proven endometriosis.

METHODS

Retrospective chart review of women aged 14-25 years who underwent laparoscopy for pelvic pain with biopsy-proven endometriosis between January 2011 and September 2020 at an academic tertiary hospital system. The final sample included 91 patients with biopsy-confirmed endometriosis.

RESULTS

Combined oral contraceptives (COCs) were the most common initial treatment (64% of patients). Progestin-only formulations (low- and high-dose norethindrone acetate) were offered to younger patients (age 15.9 ± 2.7 years) than those offered COCs (19.9 ± 3.3 years) and levonorgestrel intrauterine devices (LNG-IUDs) (21.9 ± 1.7 years). Current treatments varied widely and included COCs (32%), LNG-IUDs (18%), oral progestins (low- and high-dose norethindrone, medroxyprogesterone) (14%), elagolix (9%), and leuprolide (8%). Oral adjuncts to LNG-IUD were common: usually low- or high-dose norethindrone (37% of patients with an LNG-IUD), but also included progesterone, COCs, and elagolix.

CONCLUSIONS

Oral progestins, LNG-IUDs, and COCs were the mainstay of initial treatment. Subsequent treatments varied widely and included COCs, LNG-IUDs, oral progestins, elagolix, leuprolide, and combinations of these agents. We observed that most young women switched between therapies, suggesting that a personalised approach is often used to determine treatment plans among the wide range of options currently available. This study helps define the spectrum of treatment regimens for endometriosis in adolescent females.

Abnormal uterine bleeding: The well-known and the hidden face

Abnormal uterine bleeding (AUB) is a bleeding from the uterine corpus that is abnormal in regularity, volume, frequency or duration. It encompasses heavy menstrual bleeding, irregular menstrual bleeding and intermenstrual bleeding, which are common symptoms among women of reproductive age, impacting their overall well-being. Menstruation involves interactions between endometrial epithelial and stromal cells, immune cell influx, and changes in endometrial vasculature. These events resemble an inflammatory response with increased vessel permeability, tissue breakdown, and the arrival of innate immune cells. However, the mechanisms of menstrual cessation are poorly understood. AUB can be related to structural causes (polyp, adenomyosis, leiomyoma, malignancy/hyperplasia) and nonstructural conditions (coagulopathy, ovulatory dysfunction, endometrial, iatrogenic). While transvaginal ultrasound is the primary method for the screening of intracavitary lesions, saline infusion sonohysterography is more accurate to detect endometrial polyps and submucous leiomyomas, while hysteroscopy with biopsy remains the reference method for a definitive diagnosis. The main goals in managing AUB are addressing and correcting the underlying primary cause, if possible, and establishing a regular bleeding pattern or amenorrhea, which can be done with antifibrinolytic agents, progestins, gonadotropin-releasing hormone agonists and antagonists, or surgical interventions, each one with specific indications and limitations. Further research is necessary to assess the effectiveness and the long-term effects of various medical and surgical treatments. Meanwhile, the availability of diagnostic methods such as transvaginal ultrasound and hysteroscopy and the universal distribution of medical treatments for AUB should be prioritized by policymakers to minimize the diagnostic and treatment delay and thus reduce the risk of AUB-related anemia and the need of hysterectomy.

Experimental and new investigational drugs for the treatment of uterine fibroids

INTRODUCTION

Uterine fibroids, the most prevalent benign tumors among reproductive-age women, pose treatment challenges that range from surgical interventions to medical therapies for symptom control. Progestins and estroprogestins effectively manage uterine bleeding by suppressing dysfunctional endometrium over fibroids. While GnRH agonists represent a crucial milestone in symptom treatment, their prolonged use results in menopausal-like symptoms and irreversible bone mineral density loss. Advancements in understanding fibroid pathophysiology have prompted the exploration of new compounds to overcome current therapy limitations.

AREAS COVERED

This manuscript offers an updated overview of investigational drugs for symptomatic uterine fibroids.

EXPERT OPINION

Despite ulipristal acetate's well-established efficacy as a selective progesterone receptor modulator (SPRM) in fibroid treatment, its prescription has declined due to the rare but severe risk of liver damage. Oral GnRH antagonists, like elagolix, relugolix, and linzagolix, with their novel pharmacodynamic properties, are gaining traction in fibroid management, inducing a dose-dependent reduction in circulating sex hormone levels. Ongoing research on natural compounds, such as vitamin D and epigallocatechin gallate (EGCG), presents emerging options for treating uterine fibroids. This evolving landscape reflects the ongoing efforts to improve therapeutic outcomes for individuals with symptomatic uterine fibroids.

G protein-coupled receptors (GPCRs): advances in structures, mechanisms, and drug discovery

G protein-coupled receptors (GPCRs), the largest family of human membrane proteins and an important class of drug targets, play a role in maintaining numerous physiological processes. Agonist or antagonist, orthosteric effects or allosteric effects, and biased signaling or balanced signaling, characterize the complexity of GPCR dynamic features. In this study, we first review the structural advancements, activation mechanisms, and functional diversity of GPCRs. We then focus on GPCR drug discovery by revealing the detailed drug-target interactions and the underlying mechanisms of orthosteric drugs approved by the US Food and Drug Administration in the past five years. Particularly, an up-to-date analysis is performed on available GPCR structures complexed with synthetic small-molecule allosteric modulators to elucidate key receptor-ligand interactions and allosteric mechanisms. Finally, we highlight how the widespread GPCR-druggable allosteric sites can guide structure- or mechanism-based drug design and propose prospects of designing bitopic ligands for the future therapeutic potential of targeting this receptor family.

UHPLC-MS/MS Method Development and Validation for the Genotoxic Impurities Trimethyl Phosphate and Triisopropyl Phosphate of Elagolix Sodium

Elagolix sodium is a gonadotropin-releasing hormone (GnRH) receptor antagonist that inhibits endogenous GnRH signaling by competitively binding to GnRH receptors in the pituitary gland to treat moderate to severe pain associated with endometriosis. To keep the safety and quality of the drug, a fast quantitative method by reversed-phase ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry has been developed and validated for the identification, assay and estimation of potential genotoxic impurities trimethyl phosphate and triisopropyl phosphate in commercial batches of this active pharmaceutical ingredient in accordance with International Conference on Harmonization guidelines Q2 and M7. The method was validated by assessing specificity, sensitivity, linearity, the limit of quantification and detection, accuracy, precision and robustness for above analytes at a very low concentration, whose quantification and detection limits reached to 24 and 4.8 pg/ml, respectively, and the total run time for a single injection was 6 min.

A review of phase II and III drugs for the treatment and management of endometriosis

INTRODUCTION

Endometriosis is an estrogen-dependent disease that gives rise to pelvic pain and infertility. Although estroprogestins and progestins currently stand as the first-line treatments for this condition, demonstrating efficacy in two-thirds of patients, a significant portion of individuals experience only partial relief or symptom recurrence following the cessation of these therapies. The coexistence of superficial, deep endometriosis, and ovarian endometriomas, as three distinct phenotypes with unique pathogenetic and molecular characteristics, may elucidate the current heterogeneous biological response to available therapy.

AREAS COVERED

The objective of this review is to furnish the reader with a comprehensive summary pertaining to phase II-III hormonal treatments for endometriosis.

EXPERT OPINION

Ongoing research endeavors are directed toward the development of novel hormonal options for this benign yet debilitating disease. Among them, oral GnRH antagonists emerge as a noteworthy option, furnishing rapid therapeutic onset without an initial flare-up; these drugs facilitate partial or complete estrogen suppression, and promote prompt ovarian function recovery upon discontinuation, effectively surmounting the limitations associated with previously employed GnRH agonists. Limited evidence supports the use of selective estrogen and progesterone receptor modulators. Consequently, further extensive clinical research is imperative to garner a more profound understanding of innovative targets for novel hormonal options.

Update on the management of endometriosis-associated pain in France

The French National College of Obstetricians and Gynecologists (CNGOF) published guidelines for managing endometriosis-associated pain in 2018. Given the development of new pharmacological therapies and a review that was published in 2021, most national and international guidelines now suggest a new therapeutic approach. In addition, a novel validated screening method based on patient questionnaires and analysis of 109-miRNA saliva signatures, which combines biomarkers and artificial intelligence, opens up new avenues for overcoming diagnostic challenges in patients with pelvic pain and for avoiding laparoscopic surgery when sonography and MRI are not conclusive. Dienogest (DNG) 2 mg has been a reimbursable healthcare expense in France since 2020, and, according to recent studies, it is at least as effective as combined hormonal contraception (CHC) and can be used as an alternative to CHC for first-line treatment of endometriosis-associated pain. Since 2018, the literature concerning the use of DNG has grown considerably, and the French guidelines should be modified accordingly. The levonorgestrel intrauterine system (LNG IUS) and other available progestins per os, including DNG, or the subcutaneous implant, can be offered as first-line therapy, gonadotropin-releasing hormone (GnRH) agonists with add-back therapy (ABT) as second-line therapy. Oral GnRH antagonists are promising new medical treatments for women with endometriosis-associated pain. They competitively bind to GnRH receptors in the anterior pituitary, preventing native GnRH from binding to GnRH receptors and from stimulating the secretion of luteinizing hormone and follicle-stimulating hormone. Consequently, estradiol and progesterone production is reduced. Oral GnRH antagonists will soon be on the market in France. Given their mode of action, their efficacy is comparable to that of GnRH agonists, with the advantage of oral administration and rapid action with no flare-up effect. Combination therapy with ABT is likely to allow long-term treatment with minimal impact on bone mass. GnRH antagonists with ABT may thus be offered as second-line treatment as an alternative to GnRH agonists with ABT. This article presents an update on the management of endometriosis-associated pain in women who do not have an immediate desire for pregnancy.

Efficacy and safety of oral gonadotropin-releasing hormone antagonists in moderate-to-severe endometriosis-associated pain: a systematic review and network meta-analysis

PURPOSE

The aim of this NMA is to comprehensively analyze evidence of oral GnRH antagonist in the treatment of moderate-to-severe endometriosis-associated pain.

METHODS

Literature searching was performed to select eligible studies published prior to April 2022 in PubMed, Cochrane, Embase and Web of Science. Randomized controlled trials involving patients who suffered from moderate-to-severe endometriosis-associated pain and treated with oral nonpeptide GnRH antagonists or placebo were included.

RESULTS

Elagolix 400 mg and ASP1707 15 mg were most efficient in reducing pelvic pain, dysmenorrhea and dyspareunia. Relugolix 40 mg was best in reducing the analgesics use. The rates of any TEAEs and TEAEs-related discontinuation were highest in relugolix 40 mg and elagolix 250 mg, respectively, while rates of hot flush and headache were highest in relugolix 40 mg and elagolix 150 mg. Significantly decreased spinal BMD was observed in elagolix 250 mg.

CONCLUSION

Oral GnRH antagonists were effective in endometriosis-associated pain in 12w, and most of the efficiency and safety outcomes were expressed in a dose-dependent manner, but linzagolix 75 mg was an exception.

GnRH agonists and antagonists in therapy of symptomatic uterine fibroids - current roles and future perspectives

INTRODUCTION

Uterine fibroids are the most common noncancerous tumors in women of childbearing age. This review was developed to evaluate the current role of gonadotropin-releasing hormone (GnRH) agonists and antagonists in the therapy of symptomatic uterine fibroids.

AREAS COVERED

There is a great need for alternative methods for surgical treatment of uterine fibroids. Hormonal therapy remains the first-line treatment option for most patients. GnRH analogs (agonists and antagonists) modulate the pulsatile release of GnRH. This review summarizes the available literature concerning pharmacologic principles underlying the mechanism of action of GnRH and its analogs, as well as individual therapeutic applications to which these drugs have been applied.

EXPERT OPINION

In many cases, it is possible to try to treat uterine fibroids pharmacologically. Both groups of GnRH analogs are used in therapy, agonists instead as a preparation for surgery, and antagonists as a drug for long-term use. It is essential to develop this path further and look for at least long-term-release systems or new methods of administering these drugs. It is also important from the patient's perspective to search for possible drugs that may have an additive effect of decreasing side effects when combined with GnRH analogs.

Elagolix Sodium Salt and Its Synthetic Intermediates: A Spectroscopic, Crystallographic, and Conformational Study

Elagolix sodium salt is the first marketed orally active non-peptide gonadotropin-releasing hormone receptor antagonist (GnRHR-ant) for the management of hormone dependent diseases, such as endometriosis and uterine fibroids. Despite its presence on the market since 2018, a thorough NMR analysis of this drug, together with its synthetic intermediates, is still lacking. Hence, with the aim of filling this literature gap, we here performed a detailed NMR investigation, which allowed the complete assignment of the ¹H, ¹³C, and ¹⁵N NMR signals. These data allowed, with the support of the conformational analysis, the determination of the stereochemical profile of the two atropisomers, detectable in solution. Moreover, these latter were also detected by means of cellulose-based chiral HPLC, starting from a sample prepared through an implemented synthetic procedure with respect to the reported ones. Overall, these results contribute to further understanding of the topic of atropisomerism in drug discovery and could be applied in the design of safe and stable analogs, endowed with improved target selectivity.

Dysregulated Liver Metabolism and Polycystic Ovarian Syndrome

A significant fraction of couples around the world suffer from polycystic ovarian syndrome (PCOS), a disease defined by the characteristics of enhanced androgen synthesis in ovarian theca cells, hyperandrogenemia, and ovarian dysfunction in women. Most of the clinically observable symptoms and altered blood biomarker levels in the patients indicate metabolic dysregulation and adaptive changes as the key underlying mechanisms. Since the liver is the metabolic hub of the body and is involved in steroid-hormonal detoxification, pathological changes in the liver may contribute to female endocrine disruption, potentially through the liver-to-ovary axis. Of particular interest are hyperglycemic challenges and the consequent changes in liver-secretory protein(s) and insulin sensitivity affecting the maturation of ovarian follicles, potentially leading to female infertility. The purpose of this review is to provide insight into emerging metabolic mechanisms underlying PCOS as the primary culprit, which promote its incidence and aggravation. Additionally, this review aims to summarize medications and new potential therapeutic approaches for the disease.

Physiological and Pharmacological overview of the Gonadotropin Releasing Hormone

Gonadotropin-releasing Hormone (GnRH) is a decapeptide responsible for the control of the reproductive functions. It shows C- and N-terminal aminoacid modifications and two other distinct isoforms have been so far identified. The biological effects of GnRH are mediated by binding to high-affinity G-protein couple receptors (GnRHR), showing characteristic very short C tail. In mammals, including humans, GnRH-producing neurons originate in the embryonic nasal compartment and during early embryogenesis they undergo rapid migration towards the hypothalamus; the increasing knowledge of such mechanisms improved diagnostic and therapeutic approaches to infertility. The pharmacological use of GnRH, or its synthetic peptide and non-peptide agonists or antagonists, provides a valid tool for reproductive disorders and assisted reproduction technology (ART). The presence of GnRHR in several organs and tissues indicates additional functions of the peptide. The identification of a GnRH/GnRHR system in the human endometrium, ovary, and prostate has extended the functions of the peptide to the physiology and tumor transformation of such tissues. Likely, the activity of a GnRH/GnRHR system at the level of the hippocampus, as well as its decreased expression in mice brain aging, raised interest in its possible involvement in neurogenesis and neuronal functions. In conclusion, GnRH/GnRHR appears to be a fascinating biological system that exerts several possibly integrated pleiotropic actions in the complex control of reproductive functions, tumor growth, neurogenesis, and neuroprotection. This review aims to provide an overview of the physiology of GnRH and the pharmacological applications of its synthetic analogs in the management of reproductive and non-reproductive diseases.

Asymmetric Synthesis of US-FDA Approved Drugs over Five Years (2016–2020): A Recapitulation of Chirality

Chirality is a major theme in the design, discovery, and development of new drugs. Historically, pharmaceuticals have been synthesized as racemic mixtures. However, the enantiomeric forms of drug molecules have distinct biological properties. One enantiomer may be responsible for the desired therapeutic effect (eutomer), whereas the other may be inactive, interfere with the therapeutic form, or exhibit toxicity (distomer). Classical chemical synthesis usually leads to a racemic mixture unless stereospecific synthesis is employed. To meet the requirements of single-enantiomeric drugs, asymmetric synthesis has evolved at the forefront of drug discovery. Asymmetric synthesis involves the conversion of an achiral starting material into a chiral product. This review emphasizes the methods used for synthesizing FDA-approved chiral drugs during 2016–2020, with a special focus on asymmetric synthesis by means of chiral induction, resolution, or chiral pool.

Profile of Linzagolix in the Management of Endometriosis, Including Design, Development and Potential Place in Therapy: A Narrative Review

Estrogens play a critical role in the pathogenesis of endometriosis and it is logical to assume that lowering estradiol levels with oral gonadotropin-releasing hormone (GnRH) antagonists may prove effective, especially in women who fail to respond to progestogens. Indeed, due to progesterone resistance, oral contraceptives and progestogens work well in two-thirds of women suffering from endometriosis, but are ineffective in 33% of women. Oral GnRH antagonists have therefore been evaluated for management of premenopausal women with endometriosis-associated pelvic pain. The first publication on these drugs reported the efficacy of elagolix. The present paper is a narrative review of linzagolix, which is an orally administered GnRH receptor antagonist with low pharmacokinetic/pharmacodynamic variability. It binds to and blocks the GnRH receptor in the pituitary gland, resulting in a dose-dependent drop in luteinizing hormone (LH) and follicle-stimulating hormone (FSH) production. This reduction in LH and FSH levels in turn leads to a dose-dependent decline in estrogen. Phase 2 and 3 trials are reviewed and discussed here. There is a place for GnRH antagonists in the management of symptomatic endometriosis, and linzagolix with or without add-back therapy (ABT) is one option that can be used at low doses, avoiding the need for ABT, which is contraindicated in some patients.

Gonadotropin-Releasing Hormone Antagonists-A New Hope in Endometriosis Treatment?

Endometriosis is a chronic disease, in which endometrial-like tissue is found outside the uterine cavity. Lesions are typically located in the true pelvis but can be found, in addition to extragenital endometriosis, in the respiratory system, the diaphragm, the pleura or the pericardium. As the extrauterine endometrial lesions undergo the menstrual cycle, they cause many symptoms, including pain, and besides infertility, they all mostly affect the quality of the patient's life. Pharmacological management of endometriosis significantly increases in importance either as a first-line treatment or as a complementary therapy after surgery. Yet, current research on antagonists of the gonadotropin-releasing hormone (GnRH) has revealed their potential benefits in endometriosis treatment. Their mechanism of action is to down-regulate the hypothalamic-pituitary-gonadal axis and therefore induce a hypoestrogenic state. The resulting reduction of estrogen levels prevents disease progression and diminishes the recurrence rate after surgical removal of endometriosis. The present review summarizes recent reports of the role oral GnRH antagonists have as a significant treatment option for pain reduction in endometriosis patients.

Elagolix is porphyrogenic and may induce porphyric attacks in patients with the acute hepatic porphyrias

Elagolix is an FDA-approved treatment for moderate-to-severe pain associated with endometriosis but has been associated with increased acute porphyric attacks in women with the acute hepatic porphyrias (AHPs). A fluorescence-based screening assay for drug porphyrogenicity in LMH cells indicates that elagolix is porphyrogenic; thus, elagolix should be avoided or used with caution in patients with the AHPs.

Oral gonadotropin-releasing hormone antagonists for treating endometriosis-associated pain: a systematic review and network meta-analysis

OBJECTIVE

To review the use of oral gonadotropin-releasing hormone (GnRH) antagonists and synthesize their efficacy and safety parameters for the treatment of endometriosis-associated pain.

DESIGN

Systematic review and network meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Premenopausal women with endometriosis who had experienced moderate or severe pain.

INTERVENTION(S)

The Web of Science, Embase, Scopus, and MEDLINE were searched until April 10, 2022. Only randomized controlled trials were included. The risk of bias in the included studies was assessed using the Cochrane Risk of Bias tool 2. A Bayesian random-effects network meta-analysis was used to perform indirect comparisons. I² was used to assess the global heterogeneity. Relative treatment estimates were performed. Treatment ranking was performed through the surface under the cumulative ranking curve. The certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation framework.

MAIN OUTCOME MEASURE(S)

Endometriosis-associated pain, dysmenorrhea, dyspareunia, and noncyclic pelvic pain reduction.

RESULT

(s): Five studies and 6 randomized controlled trials, including a total of 2,796 women and 10 different doses of oral GnRH antagonist treatments, were eligible for inclusion. All studies were considered to have a low risk of bias. Almost all efficacy- and safety-related outcomes showed a dose-response relationship. Regarding endometriosis-associated pain, the top 3 treatments were elagolix 400 mg, linzagolix 75 mg, and linzagolix 200 mg, with mean differences of -1.26 (95% credible interval [CrI], -1.70 to -0.79), -0.98 (95% CrI, -1.84 to -0.15), and -0.98 (95% CrI, -1.90 to -0.064), respectively. The top 3 treatments to decrease dysmenorrhea were relugolix 40 mg, elagolix 400 mg, and relugolix 20 mg, with mean differences of -1.60 (95% CrI, -2.07 to -1.14), -1.25 (95% CrI, -1.56 to -0.95), and -1.10 (95% CrI, -1.59 to -0.62), respectively. However, only high-dose treatments were significantly associated with most quality of life- and adverse effect-related outcomes. Relugolix 40 and 20 mg and elagolix 400 mg, with odds ratios of 6.88 (95% CrI, 2.18-24.58), 1.60 (95% CrI, 0.62-4.13), and 1.85 (95% CrI, 1.05-3.30), had a significantly increased incidence of adverse events.

CONCLUSION

(s): Oral GnRH antagonists are effective for endometriosis-associated pain and dysmenorrhea and the patient global impression. The incidence of ovarian hypoestrogenic effects in a short-term duration was significant in a dose-effect response, particularly the highest dose.

CLINICAL TRIAL REGISTRATION NUMBER

International Prospective Register of Systematic Reviews registration number CRD42022332904.

Novel pharmacological therapies for the treatment of endometriosis

INTRODUCTION

Endometriosis is a chronic, estrogen-dependent, inflammatory disease associated with pelvic pain, infertility, impaired sexual function, and psychological suffering. Therefore, tailored patient management appears of primary importance to address specific issues and identify the appropriate treatment for each woman. Over the years, abundant research has been carried out with the objective to find new therapeutic approaches for this multifaceted disease.

AREAS COVERED

This narrative review aims to present the latest advances in the pharmacological management of endometriosis. In particular, the potential role of GnRH antagonists, selective progesterone receptor modulators (SPRMs), and selective estrogen receptors modulators (SERMs) will be discussed. We performed a literature search in PubMed and Embase, and selected the best quality evidence, giving preference to the most recent and definitive original articles and reviews.

EXPERT OPINION

Medical therapy represents the cornerstone of endometriosis management, although few advances have been made in the last decade. Most studies have focused on the evaluation of the efficacy and safety of GnRH antagonists (plus add-back therapy in cases of prolonged treatment), which should be used as second-line treatment options in selected cases (i.e. non-responders to first-line treatments). Further studies are needed to identify the ideal treatment for women with endometriosis.

Phenols in Pharmaceuticals: Analysis of a Recurring Motif

Phenols and phenolic ethers are significant scaffolds recurring both in nature and among approved small-molecule pharmaceuticals. This compendium presents the first comprehensive compilation and analysis of the structures of U.S. FDA-approved molecules containing phenol or phenolic ether fragments. This dataset comprises 371 structures, which are strongly represented by natural products. A total of 55 of the compounds described here are on the World Health Organization's list of essential medicines. Structural analysis reveals significant differences in the physicochemical properties imparted by phenols versus phenol ethers, each having benefits and drawbacks for drug developability. Despite trends over the past decade to increase the fraction of sp³ centers in drug leads, thereby "escaping flatland", phenols and phenolic ethers are represented in 62% of small-molecule drugs approved in 2020, suggesting that this aromatic moiety holds a special place in drugs and natural products.

Review of human genetic and clinical studies directly relevant to GnRH signalling

GnRH is the pivotal hormone in controlling the hypothalamic-pituitary gonadal (HPG) axis in humans and other mammalian species. GnRH function is influenced by a multitude of known and still unknown environmental and genetic factors. Molecular genetic studies on human families with hypogonadotropic hypogonadism over the past two decades have been instrumental in delineating the kisspeptin and neurokinin B signalling, which integrally modulates GnRH release from the hypothalamus. The identification of kisspeptin and neurokinin B ligand-receptor gene pair mutations in patients with absent puberty have paved the way to a greater understanding of the central regulation of the HPG cascade. In this article, we aim to review the literature on the genetic and clinical aspects of GnRH and its receptor, as well as the two ligand-receptor sets directly pertinent to the function of GnRH hormone signalling, kisspeptin/ kisspeptin receptor and NKB/NK3R.

Effects of Elagolix on the Pharmacokinetics of Omeprazole and its Metabolites in Healthy Premenopausal Women

This study evaluated the effect of repeated doses of elagolix on the pharmacokinetics of omeprazole and its metabolites in healthy premenopausal female subjects. Adult premenopausal female subjects (N = 20) received a single oral dose of omeprazole (40 mg) on Day 1 and Day 11 and oral doses of elagolix (300 mg) twice-daily on Days 3 to 11. Serial blood samples for assay of omeprazole and its metabolites were collected for 24 hours after dosing on Days 1 and 11. Pharmacokinetic parameters were calculated for omeprazole, 5-hydroxyomeprazole and omeprazole sulfone; and were compared between Day 1 and Day 11. Pharmacogenetic testing was performed for CYP2C19 variant alleles and the results were used to compare the magnitude of elagolix-omeprazole DDI between the different genotype subgroups. Administration of elagolix 300 mg twice-daily for 9 days increased omeprazole exposure by 1.8-fold and decreased the metabolite-to-parent ratio for 5-hydroxyomeprazole by ~60%. Conversely, there was an increase in the metabolite-to-parent ratio for omeprazole sulfone by 25%. Elagolix increased omeprazole exposures by 2- to 2.5-fold in CYP2C19 Extensive and Intermediate Metabolizer subjects, but decreased omeprazole exposures by 40% in Poor Metabolizer subjects. Exposures of 5-hydroxyomeprazole decreased by 20-30% in all genotype subgroups, and omeprazole sulfone exposures increased by ~3-fold in Extensive and Intermediate Metabolizer subjects. Elagolix is a weak inhibitor of CYP2C19 and exposure of CYP2C19 substrates may be increased upon coadministration with elagolix. Omeprazole may exhibit drug interactions due to multiple mechanisms other than CYP2C19-mediated metabolism; complicating the interpretation of results from omeprazole DDI studies.

GnRH Antagonists with or without Add-Back Therapy: A New Alternative in the Management of Endometriosis?

To evaluate the effectiveness of a new class of medical drugs, namely oral gonadotropin-releasing hormone (GnRH) antagonists, in the management of premenopausal women with endometriosis-associated pelvic pain. We reviewed the most relevant papers (n = 27) on the efficacy of new medical alternatives (oral GnRH antagonists) as therapy for endometriosis. We first briefly summarized the concept of progesterone resistance and established that oral contraceptives and progestogens work well in two-thirds of women suffering from endometriosis. Since clinical evidence shows that estrogens play a critical role in the pathogenesis of the disease, lowering their levels with oral GnRH antagonists may well prove effective, especially in women who fail to respond to progestogens. There is a need for reliable long-term oral treatment capable of managing endometriosis symptoms, taking into consideration both the main symptoms and phenotype of the disease. Published studies reviewed and discussed here confirm the efficacy of GnRH antagonists. There is a place for GnRH antagonists in the management of symptomatic endometriosis. Novel algorithms that take into account the different phenotypes are proposed.

Breakthrough Bleeding in Transgender and Gender Diverse Adolescents and Young Adults on Long-Term Testosterone

STUDY OBJECTIVE

Amenorrhea is a goal of many transgender and gender diverse adolescent and young adult (TGD AYA) patients on testosterone gender-affirming hormone therapy (T-GAHT). Breakthrough bleeding can contribute to worsening gender dysphoria. Our objective was to evaluate breakthrough bleeding in TGD AYA on T-GAHT.

DESIGN

Institutional review board-approved retrospective cohort.

SETTING

Tertiary-care children's hospital.

PARTICIPANTS

TGD AYA on T-GAHT >1 year.

INTERVENTIONS

None; observational.

MAIN OUTCOME MEASURES

Presence of, and risk factors for, breakthrough bleeding.

RESULTS

Of the 232 patients who met inclusion criteria, one-fourth (n = 58) had 1 or more episodes of breakthrough bleeding, defined as bleeding after more than 1 year on T-GAHT. In comparing patients with breakthrough bleeding to those without, there were no significant differences between age of initiation, body mass index (BMI), race/ethnicity, testosterone type used, use of additional menstrual suppression, serum testosterone, or estradiol levels. Patients with breakthrough bleeding patients were on T-GAHT longer (37.3 ± 17.0 vs 28.5 ± 14.6 months, P < .001) and were more likely to have endometriosis (P = .049). Breakthrough bleeding began at a mean of 24.3 ± 17.2 months after T-GAHT initiation. Of those with breakthrough bleeding, 46 (79.3%) had no known cause, 10 (17.2%) bled only with missed T-GAHT doses, and 2 (3.4%) bled only when withdrawing from concomitant menstrual suppression. No breakthrough bleeding management method was found to be superior.

CONCLUSION

Breakthrough bleeding is relatively common (25%) on T-GAHT despite early amenorrhea. Most cases do not have an identifiable cause. Our data did not show superiority of any 1 method for managing breakthrough bleeding on T-GAHT.

Linzagolix: a new GnRH-antagonist under investigation for the treatment of endometriosis and uterine myomas

INTRODUCTION

Uterine myomas and endometriosis are benign hormone-dependent diseases affecting women of reproductive age. Substantial efforts have been made to develop innovative medical options for treating these gynecologic diseases. Elagolix and relugolix have been approved in some countries for treating endometriosis and myomas, respectively; however, linzagolix (OBE 2109, KLH 2109) is a new oral gonadotropin-releasing hormone (GnRH) antagonist in phase II-III trials. Treatment options for women with contraindications for hormonal therapies or who refuse particular options, are the driving force behind the development of new drugs in this area.

AREA COVERED

This drug evaluation highlights definitive and preliminary results from previous and ongoing studies of linzagolix for the treatment of endometriosis and myomas.

EXPERT OPINION

Linzagolix showed a dose-dependent and rapidly reversible action on the pituitary-gonadal axis. In a recent phase II trial (EDELWEISS), linzagolix significantly reduced pain related to endometriosis and improved quality of life at single daily doses of 75-200 mg. The preliminary results of international, double-blind phase III trials (PRIMROSE 1 and 2) reported its efficacy in treating heavy menstrual bleeding related to myomas with a good safety profile. Further studies will determine the necessity of add-back therapy during long-term use of linzagolix.

Thromboembolic safety profile of low-dose estradiol (valerate) in combined hormonal preparations: Implications for the development of new hormonal endometriosis and uterine fibroid therapies

Background:

Several promising new medications containing low-dose estradiol (E2) in combination with a progestin and an additional component, such as gonadotropin-releasing hormone antagonists, are currently being developed for use in pre-menopausal women.

Objective:

This pooled analysis was designed to estimate the thromboembolic safety profile of E2 and its ester, estradiol valerate (E2Val), when used in combined hormonal treatments in a pre-menopausal population.

Methods:

Data regarding users of combined oral contraceptives (COCs) and combined menopausal hormonal therapy (MHT) containing either E2/E2Val or ethinylestradiol (EE) ⩽ 30 µg were retrieved from five large prospective, non-interventional, cohort studies in Europe, US, and Canada with similar study design but differing medication cohorts. Propensity score sub-classification was applied to balance baseline parameters between cohorts and time-to-event analysis of venous thromboembolic events (VTE) was carried out based on the extended Cox model to calculate crude and adjusted hazard ratios (HR).

Results:

(1) Crude incidence rates of VTE were higher in MHT users compared to pre-menopausal COC users, (2) the VTE risk in menopausal users of E2/E2Val-norethindrone acetate was not higher than that in menopausal users of E2/E2Val-progestin (adjusted HR 0.71; 95% confidence interval, 0.41-1.26) and (3) the VTE risk in pre-menopausal users of E2/E2Val-progestin was similar, or lower, than pre-menopausal users of EE⩽30µg-progestin (adjusted HR 0.49; 95% confidence interval, 0.28–0.84).

Conclusion:

Our data presents a solid safety assessment of combined hormonal preparations containing E2/E2Val. We conclude that the risk of E2/E2Val-norethindrone acetate in pre-menopausal users is unlikely to be higher than the known risk of COCs containing EE ⩽ 30 µg-progestin.

Validation of a quantitative systems pharmacology model of calcium homeostasis using elagolix Phase 3 clinical trial data in women with endometriosis

Elagolix is a novel, oral gonadotropin‐releasing hormone receptor antagonist indicated for the management of moderate to severe pain associated with endometriosis and heavy menstrual bleeding associated with uterine fibroids. Consistent with its mechanism of action, elagolix exhibited dose‐dependent suppression of estradiol (E2) in clinical studies. A dose‐response model that describes the relationship between elagolix dosages and average E2 levels was combined with a previously published quantitative systems pharmacology (QSP) model of calcium homeostasis to predict bone mineral density (BMD) changes during and following elagolix treatment. In the QSP model, changes in E2 levels were linked to downstream changes in markers of bone resorption (carboxyterminal cross‐linked telopeptide of type 1 collagen [CTX]), formation (N‐terminal propeptide of type 1 procollagen [P1NP]) and BMD. The BMD, CTX, and P1NP predictions by the QSP model were validated against observed data from four phase III clinical trials of elagolix in premenopausal women with endometriosis. BMD, CTX, and P1NP were successfully described by the QSP model, without any model fitting, suggesting that the model was validated for further predictions of elagolix effects on BMD. Simulations using the validated QSP model demonstrated that elagolix 150 mg once daily dosing for 24 months is predicted to result in −0.91% change from baseline in lumbar spine BMD. The QSP model simulation results were part of the totality of evidence to support the approved duration of therapy for elagolix 150 mg once daily in patients with endometriosis.

Elagolix in the treatment of heavy menstrual bleeding associated with uterine fibroids in premenopausal women

INTRODUCTION

Uterine fibroids (UFs) are the most common benign tumor arising from myometrium of reproductive age women, with significant financial burden estimated in hundreds of billions of dollars. Unfortunately, there are limitations in available long-term treatment options. Thus, there is a large unmet need in the UF space for noninvasive therapeutics.

AREAS COVERED

Authors reviewed the literature available for elagolix; an orally bioavailable, second-generation, non-peptide gonadotropin-releasing hormone (GnRH) antagonist recently approved by the US Food and Drug Administration (FDA) in combination with estradiol/norethindrone acetate for the management of heavy menstrual bleeding associated with UFs in premenopausal women.

EXPERT OPINION

The utility of new-generation oral GnRH-antagonists, such as elagolix, relugolix and linzagolix, is offering a new potential opportunity for the future therapy of UFs: elagolix has been the most studied drug of this class for treating benign gynecological diseases, including endometriosis and UFs, for which it has been US FDA-approved in 2018 and 2020, respectively.

Endometriosis and Medical Therapy: From Progestogens to Progesterone Resistance to GnRH Antagonists: A Review

Background: The first objective of this review was to present, based on recent literature, the most frequently applied medical options (oral contraceptive pills (OCPs) and progestogens) for the management of symptomatic endometriosis, and evaluate their effectiveness in treating premenopausal women with endometriosis-associated pelvic pain, dysmenorrhea, non-menstrual pelvic pain and dyspareunia. The second objective was to review the concept of progesterone resistance and newly available treatment options. Methods: We reviewed the most relevant papers (n = 73) on the efficacy of OCPs and progestogens as medical therapy for endometriosis, as well as those on progesterone resistance and new medical alternatives (oral gonadotropin-releasing hormone (GnRH) antagonist). Eleven papers, essentially reviews, were selected and scrutinized from among 94 papers discussing the concept of progesterone resistance. Results: Having reviewed the most significant papers, we can confirm that OCPs and progestogens are effective in two-thirds of women suffering from endometriosis, but that other options are required in case of failure (in one-third of women due to progesterone resistance) or intolerance to these compounds. It is clear that there is a need for effective long-term oral treatment capable of managing endometriosis symptoms, while mitigating the impact of side effects. Biochemical, histological and clinical evidence show that estrogens play a critical role in the pathogenesis of endometriosis, so lowering levels of circulating estrogens should be considered an effective medical approach. The efficacy of three oral GnRH antagonists is discussed on the basis of published studies. Conclusion: There is a place for GnRH antagonists in the management of symptomatic endometriosis and clinical trials should be conducted, taking into account the different phenotypes in order to propose novel algorithms.

U.S. FDA Approved Drugs from 2015-June 2020: A Perspective

In the present work, we report compilation and analysis of 245 drugs, including small and macromolecules approved by the U.S. FDA from 2015 until June 2020. Nearly 29% of the drugs were approved for the treatment of various types of cancers. Other major therapeutic areas of focus were infectious diseases (14%); neurological conditions (12%); and genetic, metabolic, and cardiovascular disorders (7-8% each). Itemization of the approved drugs according to the year of approval, sponsor, target, chemical class, major drug-metabolizing enzyme(s), route of administration/elimination, and drug-drug interaction liability (perpetrator or/and victim) is presented and discussed. An effort has been made to analyze the pharmacophores to identify the structural (e.g., aromatic, heterocycle, and aliphatic), elemental (e.g., boron, sulfur, fluorine, phosphorus, and deuterium), and functional group (e.g., nitro drugs) diversity among the approved drugs. Further, descriptor-based chemical space analysis of FDA approved drugs and several strategies utilized for optimizing metabolism leading to their discoveries have been emphasized. Finally, an analysis of drug-likeness for the approved drugs is presented.

Gonadotropin-releasing hormone analogs: Mechanisms of action and clinical applications in female reproduction

Extra-hypothalamic GnRH and extra-pituitary GnRH receptors exist in multiple human reproductive tissues, including the ovary, endometrium and myometrium. Recently, new analogs (agonists and antagonists) and modes of GnRH have been developed for clinical application during controlled ovarian hyperstimulation for assisted reproductive technology (ART). Additionally, the analogs and upstream regulators of GnRH suppress gonadotropin secretion and regulate the functions of the reproductive axis. GnRH signaling is primarily involved in the direct control of female reproduction. The cellular mechanisms and action of the GnRH/GnRH receptor system have been clinically applied for the treatment of reproductive disorders and have widely been introduced in ART. New GnRH analogs, such as long-acting GnRH analogs and oral nonpeptide GnRH antagonists, are being continuously developed for clinical application. The identification of the upstream regulators of GnRH, such as kisspeptin and neurokinin B, provides promising potential to develop these upstream regulator-related analogs to control the hypothalamus-pituitary-ovarian axis.

Patient preferences for elagolix and leuprolide for treating endometriosis-related pain in the United States

INTRODUCTION

We evaluated elagolix and leuprolide from the patient's perspective for the treatment of endometriosis-related pain.

AREA COVERED

Preference weights from a published discrete choice experiment were used to evaluate preferences for treatment profiles simulating elagolix (150 mg/day and 200 mg/twice-daily dosages) and leuprolide for the treatment of moderate to severe endometriosis-related pain. Sensitivity analyses were conducted by varying the range of risk for pregnancy-related problems, moderate to severe hot flashes, and bone fracture across scenarios.

EXPERT OPINION

The 200 mg twice daily dosage of elagolix is more likely to be preferred over leuprolide by patients with moderate to severe endometriosis-related pain in all scenarios explored in the evaluation and sensitivity analyses. The probability that an average respondent would select a treatment was sensitive to increases in risk of moderate to severe hot flashes for leuprolide and possible variations in the risk of pregnancy-related problems for both treatments but was not influenced by an increased risk of bone fracture.

CONCLUSIONS

Patients' preferences for treatment of endometriosis-related pain should be evaluated using the benefits and risks of each pharmacological option. Respondents were more likely to prefer the treatment profile similar to 200 mg twice daily elagolix over that of leuprolide in all scenarios.

Structure of the human gonadotropin-releasing hormone receptor GnRH1R reveals an unusual ligand binding mode

Gonadotrophin-releasing hormone (GnRH), also known as luteinizing hormone-releasing hormone, is the main regulator of the reproductive system, acting on gonadotropic cells by binding to the GnRH1 receptor (GnRH1R). The GnRH-GnRH1R system is a promising therapeutic target for maintaining reproductive function; to date, a number of ligands targeting GnRH1R for disease treatment are available on the market. Here, we report the crystal structure of GnRH1R bound to the small-molecule drug elagolix at 2.8 Å resolution. The structure reveals an interesting N-terminus that could co-occupy the enlarged orthosteric binding site together with elagolix. The unusual ligand binding mode was further investigated by structural analyses, functional assays and molecular docking studies. On the other hand, because of the unique characteristic of lacking a cytoplasmic C-terminal helix, GnRH1R exhibits different microswitch structural features from other class A GPCRs. In summary, this study provides insight into the ligand binding mode of GnRH1R and offers an atomic framework for rational drug design.

An Evidence-Based Review of Elagolix for the Treatment of Pain Secondary to Endometriosis

Purpose of Review

This is a review of elagolix use for pain related to endometriosis. It summarizes the background and recent data available about the pathogenesis of endometriosis and pain that is secondary to this syndrome. It then reviews the evidence to support the use of elagolix and the indications for use.

Recent Findings

Endometriosis occurs in 10% of reproductive-age women and is a common source of chronic pelvic pain, infertility, and co-morbid disorders. It usually presents with some combination of dysmenorrhea, dyspareunia, chronic pelvic pain, and infertility. Treatment options may be surgical or hormonal. Traditional treatment is divided into medical and surgical. The latter, though effective, is reserved for surgical emergencies and patients failing medical management. Medical management with NSAIDs is usually limited in efficacy. It is generally based on hormonal suppression leading to atrophy of endometrial lesions. Elagolix (Orlissa) is a GnRH antagonist that suppressed the entire hypophysis-gonadal axis. Reduced levels of estrogen and progesterone lead to involution of the endometrial lesions and improvement in symptoms. Clinical trials showed that elagolix is effective in treating dysmenorrhea and non-menstrual pain that is secondary to endometriosis. It is well tolerated and has a relatively safe usage profile. Studies up to 12 months long showed continued efficacy and reduction in dysmenorrhea of up to 75%, with 50%-60% reduction in non-menstrual pain. Elagolix was found effective when compared to both placebo and alternative treatments.

Summary

Endometriosis is a common syndrome that causes significant pain, morbidity, and disability, as well as financial loss. Elagolix is an effective drug in treating the symptoms of endometriosis and is a relatively safe option. Phase 4 studies will be required to evaluate the safety and efficacy of long term chronic use.

Relugolix, an oral gonadotropin-releasing hormone receptor antagonist, reduces endometriosis-associated pain in a dose-response manner: a randomized, double-blind, placebo-controlled study

OBJECTIVE

To evaluate the efficacy and safety of three dose levels of relugolix, a gonadotropin-releasing hormone receptor antagonist, compared with placebo and leuprorelin in women with endometriosis-associated pain.

DESIGN

Phase 2, multicenter, randomized, double-blind, placebo-controlled study.

SETTING

Hospitals and clinics.

PATIENT(S)

Adult premenopausal women with endometriosis who had dysmenorrhea and endometriosis-associated pelvic pain.

INTERVENTION(S)

During a 12-week treatment period, patients received relugolix 10 mg (n = 103), 20 mg (n = 100), or 40 mg (n = 103) as a daily oral dose; placebo (n = 97) as a daily oral dose; or leuprorelin 3.75 mg (n = 80) as a monthly subcutaneous injection.

MAIN OUTCOME MEASURE(S)

Primary endpoint was the change from baseline in mean visual analog scale score for pelvic pain during 28 days before the end of treatment.

RESULT(S)

The mean changes in mean visual analog scale score for pelvic pain were -3.8 mm in the placebo group; -6.2, -8.1, and -10.4 mm in the relugolix 10-mg, 20-mg, and 40-mg groups; respectively; and -10.6 mm in the leuprorelin group. The major adverse events with relugolix were hot flush, metrorrhagia, menorrhagia, and irregular menstruation, and bone mineral density decrease in a dose-response manner, which were also observed in the leuprorelin group with a frequency comparable with that in the relugolix 40-mg group.

CONCLUSION(S)

Oral administration of relugolix alleviated endometriosis-associated pain in a dose-response manner and was generally well tolerated. Relugolix 40 mg demonstrated efficacy and safety comparable with those of leuprorelin.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01458301.

Relugolix for the treatment of uterine fibroids

INTRODUCTION

Uterine fibroids (UF) are benign tumors common in premenopausal women, with strong impact on the health-care systems. For many years, surgery represented the only therapy for symptomatic fibroids. However, clinicians are observing a switch from surgery to noninvasive methods; in particular, medical treatment has been shown to be efficacious in obtaining a bleeding reduction and in ameliorating patient conditions.

AREAS COVERED

The authors review the current options available for the treatment of women with UF, with a special focus on the newest one, relugolix. It is an orally active non-peptide Gonadotropin-releasing hormone (GnRH)-receptor antagonist recently licensed for women with symptomatic fibroids. Relugolix is a well-tolerated safe drug; it is effective in inducing a dose-dependent decrease in menstrual blood loss, with faster reduction of heavy menstrual bleeding (HMB) and a greater shrinkage in fibroid volume compared to the current standard of GnRH agonist treatment.

EXPERT OPINION

Relugolix is a promising drug for the non-surgical treatment of women with UF. To date, the only published data come from a well-selected Japanese female population study while results from worldwide ongoing studies are ongoing in order to confirm the efficacy of this GnRH agonist receptor.

Tailor-Made Amino Acids and Fluorinated Motifs as Prominent Traits in Modern Pharmaceuticals

Structural analysis of modern pharmaceutical practices allows for the identification of two rapidly growing trends: the introduction of tailor-made amino acids and the exploitation of fluorinated motifs. Curiously, the former represents one of the most ubiquitous classes of naturally occurring compounds, whereas the latter is the most xenobiotic and comprised virtually entirely of man-made derivatives. Herein, 39 selected compounds, featuring both of these traits in the same molecule, are profiled. The total synthesis, source of the corresponding amino acids and fluorinated residues, and medicinal chemistry aspects and biological properties of the molecules are discussed.

Dienogest and the Risk of Endometriosis Recurrence Following Surgery: A Systematic Review and Meta-analysis

STUDY OBJECTIVE

To determine whether dienogest therapy after endometriosis surgery reduces the risk of endometriosis recurrence compared with expectant management.

DATA SOURCES

Ovid MEDLINE, Ovid EMBASE, PubMed, Cochrane Central Register of Controlled Trials, Web of Science, LILACS, clinicaltrials.gov, and International Standard Randomized Controlled Trial Number Registry were searched from inception to March 2019 for observational and randomized controlled trials.

METHODS OF STUDY SELECTION

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Medical Subject Heading terms and keywords such as "dienogest," "endometriosis," and "recurrence" were used to identify relevant studies.

TABULATION, INTEGRATION, AND RESULTS

The search yielded 328 studies, 10 of which were eligible for inclusion, representing 1184 patients treated with dienogest and 846 expectantly managed controls. Among these studies, 9 looked exclusively at endometrioma recurrence, whereas 1 used reappearance of symptoms as evidence of disease recurrence. Data on both incidence of and time to recurrence of endometriosis were extracted. The incidence rate of endometriosis recurrence in patients treated with dienogest was 2 per 100 women over a mean follow-up of 29 months (95% confidence interval [CI], 1.43-3.11) versus 29 per 100 women managed expectantly over a mean follow-up of 36 months (95% CI, 25.66-31.74). The likelihood of recurrence was significantly reduced with postoperative dienogest (log odds -1.96, CI, -2.53 to -1.38, p <.001).

CONCLUSION

Patients receiving dienogest after conservative surgery for endometriosis had significantly lower risk of postoperative disease recurrence than those who were expectantly managed.

The potential role of elagolix for treating uterine bleeding associated to uterine myomas

INTRODUCTION

Uterine myomas represents a widespread gynecological disease of women in reproductive age. Although surgery remains the first choice for treating most patients, in the last years, new medical approaches have been considered in order to ameliorate heavy menstrual bleeding (HMB) related to their presence. Elagolix is a second-generation gonadotropin-releasing hormone (GnRH) antagonist under investigation for the long-term treatment of uterine myomas.

AREAS COVERED

The aim of this drug evaluation is to give a complete overview of pharmacokinetic and pharmacodynamic data on elagolix for treating HMB related to uterine myomas and to report the results of the current clinical trials in this setting.

EXPERT OPINION

In two previous phase II studies, this drug succeeded in ameliorating blood loss and quality of life of patients affected by uterine myomas with a good safety profile. Three phase III trials (ELARIS UF-I, UF-II, and EXTEND) investigated the efficacy, tolerability, and safety of elagolix at 300 mg twice daily with add-back therapy. The primary endpoint, consisting in the reduction in HMB compared to placebo, was met in the majority of patients under treatment. Currently, elagolix is under investigation in two other ongoing multicenter phase III clinical studies.

Clinical Utility Of Elagolix As An Oral Treatment For Women With Uterine Fibroids: A Short Report On The Emerging Efficacy Data

Uterine fibroids (UFs) are the most common gynaecological benign disease. Even though often asymptomatic, UFs can worsen women’s health and their quality of life, causing heavy bleeding and anaemia, pelvic discomfort and reduced fertility. Surgical treatment of UFs could be limited by its invasiveness and the desire to preserve fertility. Thus, effective medical therapies for the management of this condition are needed. Common drugs used to control bleeding, such us hormonal contraceptive or levonorgestrel-releasing intrauterine system, have no effect on fibroids volume. Among other more efficient treatments, the gonadotropin-releasing hormone (GnRH) agonist or the selective progesterone-receptor modulators have a non-neutral safety profile; thus, they are used for limited periods or for cyclic treatments. Elagolix is a potent, orally bioavailable, non-peptide GnRH antagonist that acts by a competitive block of the GnRH receptor. The biological effect is a dose-dependent inhibition of gonadal axis, without a total suppression of estradiol concentrations. For this reason, even though comparative studies between elagolix and GnRH agonists have not been performed, elagolix has been associated with a better profile of adverse events. Recently, elagolix received US FDA approval for the treatment of moderate to severe pain caused by endometriosis. Several clinical trials assessed the efficacy of elagolix for the treatment of heavy bleeding caused by UFs and the definitive results of Phase III studies are expected. Available data on elagolix and UFs showed that the drug, with or without low-dose hormone add-back therapy, is able to significantly reduce menstrual blood loss, lead to amenorrhea and improve haemoglobin concentrations in the majority of participants in comparison with placebo. The safety and tolerability profile appeared generally acceptable. The concomitant use of add-back therapy can prevent bone loss due to the hypoestrogenic effect and can improve safety during elagolix treatment.

Fertility Preservation in Women With Malignancy: Future Endeavors

The area of fertility preservation is constantly developing. To date, the only noninvestigational and unequivocally accepted methods for fertility preservation are cryopreservation of embryos and unfertilized oocytes. This article is one of several in a monogram on fertility preservation. The debate, pros and cons, and equivocal data on the use of GnRH analogues for fertility preservation are elaborated by 3 other manuscripts, in this monogram. A repeat of the arguments, pros and cons of this debatable issue, would be a repetition and redundancy of what is already included in this monogram. The subject of ovarian cryopreservation for fertility preservation is also elaborated by several other authors in this monogram. It is possible that, in the not too far future, the technologies of in vitro maturation of primordial follicles to metaphase 2 oocytes, and the “artificial ovary,” will turn clinically available. These technologies may bypass the risk of resuming malignancy by autotransplantation of cryopreserved-thawed ovarian tissue in leukemia and diseases where malignant cells may persist in the cryopreserved ovarian tissue. We summarize here the suggested options for future endeavors in fertility preservation.

Fluorine-Containing Drugs Approved by the FDA in 2018

Over the last two decades, fluorine substitution has become one of the essential structural traits in modern pharmaceuticals. Thus, about half of the most successful drugs (blockbuster drugs) contain fluorine atoms. In this review, we profile 17 fluorine-containing drugs approved by the food and drug administration (FDA) in 2018. The newly approved pharmaceuticals feature several types of aromatic F and CF₃ , as well as aliphatic (CF₂ ) substitution, offering advances in the treatment of various diseases, including cancer, HIV, malarial and smallpox infections.

Elagolix as a Novel Treatment for Endometriosis-Related Pain

Endometriosis, which is the growth of endometrial tissue outside of the uterus, is estimated to affect up to 10% of reproductive-age women. Symptoms associated with endometriosis include dysmenorrhea, chronic pelvic pain, and dyspareunia. In July 2018, the U.S. Food and Drug Administration approved elagolix (Orilissa, AbbVie, North Chicago, IL) as an oral treatment for endometriosis-related pain. This medication is a gonadotropin-releasing hormone receptor antagonist that works by suppressing levels of hormones, including estrogen and progesterone. This helps decrease inflammation and the proliferation of endometrial tissue. In this column, I provide an overview of elagolix and discuss contraindications, adverse effects, and practice implications for nurses who work with women affected by endometriosis.