Overview of elagolix for the treatment of endometriosis

The short- and mid-term efficacy and safety of elagolix in the management of pain associated with endometriosis: A systematic review and meta-analysis

BACKGROUND

Elagolix, an approved non-peptide GnRH antagonist, shows promise in relieving endometriosis-related pain, but its short- and mid-term efficacy and potential side effects are still under investigation.

OBJECTIVE

The aim is to provide data for therapeutic applications by methodically evaluating elagolix's safety and effectiveness in treating endometriosis-related pain.

METHODS

Databases such as PubMed, Embase, Cochrane Library, Web of Science, ClinicalTrials.gov, and others were thoroughly searched. The search time was from the establishment date to September 2023. The study included randomized controlled trials (RCTs) that compared the efficacy of elagolix versus placebo in treating endometriosis-associated pain. After data extraction and literature scanning, quality assessment was carried out using Quality evaluation was carried out using the bias risk assessment tool suggested by the Cochrane Reviewers' Handbook 5.1.0 after literature screening and data extraction. Stata 15.0 was used to do the meta-analysis.

RESULTS

In total, five RCTs involving 2056 patients were included in the analysis. The meta-analysis demonstrated a significant superiority of elagolix over placebo in the management of endometriosis-related pain, specifically in endometriosis pain [WMD=-0.77, 95% CI (-1.00, -0.53), P<0.001], as well as in non-menstrual pelvic pain, daily assessment of dysmenorrhea (DYS), and dyspareunia (DYSP), all of which are associated with endometriosis. Regarding safety, no discernible variation was observed in the incidence of serious adverse responses between the elagolix and placebo groups [RR=0.90, 95% CI (0.58, 1.40), P=0.643]. Conversely, the elagolix group exhibited a significantly higher incidence rate of general adverse responses [RR = 1.34, 95% CI (1.18, 1.52), P<0.001] compared to the control group.

CONCLUSIONS

The efficacy of elagolix in reducing pain in premenopausal women with endometriosis has been demonstrated over the short- to mid-term. However, careful monitoring for potential adverse effects is essential throughout the treatment duration.

Post-marketing safety concerns with elagolix: a disproportionality analysis of the FDA adverse event reporting system

OBJECTIVE

Elagolix is approved for the treatment of moderate-to-severe pain associated with endometriosis. However, the long-term safety of elagolix in a large sample of real-world patients is unknown.

METHODS

The U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) reports were collected and analyzed from January 2019 to June 2023. Disproportionality analyses, including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS) algorithms, were employed in data mining to quantify the signals of elagolix-related adverse events (AEs).

RESULTS

After removing the non-drug-related AE signals, we detected several AE signals such as hot flushes, bone pain, suicidal ideation, depression, and increased liver enzymes, which were known during the clinical trial phase. In addition to this, we detected several unexpected important AEs that were not mentioned in the drug insert, including cystitis interstitial, parosmia, and epiploic appendagitis. The median onset time of elagolix-associated AEs was 28.5 days.

CONCLUSION

Our study provides a comprehensive picture of the safety of elagolix in the post-marketing setting, while also identifying potential new AE signals. These findings emphasize the importance of continued monitoring of the potential risks of elagolix.

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.

Forced degradation studies of elagolix sodium with the implementation of high resolution LC-UV-PDA-MSn (n = 1,2,3…) and NMR structural elucidation

Elagolix sodium (ELS) is a marketed product using to release moderate to severe endometriosis-associated pain. It contains functional groups such as carboxyl group, secondary amino group, 2,4-dioxo pyrimidinyl and several benzyl or benzyl-like position hydrogen atom that are susceptive to occur stress degradation. Forced degradation studies of ELS reveal different degradation profiles of the drug substance which are conducted under photo, thermal, acidic, neutral, alkaline and hydrogen peroxide oxidative conditions in the direction of the ICH guidances. With structural elucidation of LC-PDA/UV-MSⁿ and NMR, the degradants were identified, and seven new degradants are reported in this study. It is confirmed that most of the degradation behaviors of ELS are related to the carboxyl group and secondary amino group in the 3-carboxyl propylamine side chain. Under the oxidative condition using hydrogen peroxide as the oxidant, the secondary amine was oxidized to form an N-hydrogen amine degradant and two further degradants of amine and carbonyl analogs were generated. Under the alkaline degradation condition, the ELS is proven to be stable and no obvious degradants are produced. On the other hand, under the acidic and neutral degradation condition, the 2,4-dioxo pyrimidinyl core of elagolix sodium is stable but the carboxyl group and secondary amine will occur ring cyclization to form the δ-lactam analogs of elagolix sodium. The plausible mechanisms for the degradation of acidic, thermal, photo-degradative and hydrogen peroxide mediated oxidative of elagolix sodium are proposed. It is worth to note that DP-3-4 are the potential degradants which are only found in the solution degradation and are not the real impurities of elagolix sodium.

Gas Chromatography-Mass Spectrometry (GC-MS) Metabolites Analysis in Endometriosis Patients: A Prospective Observational Translational Study

BACKGROUND

Endometriosis affects women of reproductive age, and its pathogenesis is still unclear. Typically, it overlaps other similar medical and surgical conditions, determining a delay in early diagnosis. Metabolomics allows studying metabolic changes in different physiological or pathological states to discover new potential biomarkers. We used the gas chromatography-mass spectrometer (GC-MS) to explore metabolic alterations in endometriosis to better understand its pathophysiology and find new biomarkers.

METHODS

Twenty-two serum samples of patients with symptomatic endometriosis and ten without it were collected and subjected to GC-MS analysis. Multivariate and univariate statistical analyses were performed, followed by pathway analysis.

RESULTS

Partial least squares discriminant analysis was performed to determine the differences between the two groups (p = 0.003). Threonic acid, 3-hydroxybutyric acid, and proline increased significantly in endometriosis patients, while alanine and valine decreased. ROC curves were built to test the diagnostic power of metabolites. The pathway analysis identified the synthesis and degradation of ketone bodies and the biosynthesis of phenylalanine, tyrosine, and tryptophan as the most altered pathways.

CONCLUSIONS

The metabolomic approach identifies metabolic alterations in women with endometriosis. These findings may improve our understanding of the pathophysiological mechanisms of disease and the discovery of new biomarkers.

Deep Endometriosis and Infertility: What Is the Impact of Surgery?

In women with deep endometriosis, the spontaneous fertility rate might range from 2 to 10%. The optimal management of these women is still an area of debate. Therefore, this review aims to explore the literature on the impact of deep endometriosis surgery on reproductive outcomes and pregnancy rates in women with and without prior infertility. A total of 392 articles were identified through database searching. Twenty-three studies were eligible to be included in the review. A total of 1548 women were identified, 814 of whom became pregnant, with a mean pregnancy rate of 52.6% (95% CI 49.7-63%). Our review suggests that surgery may improve fertility outcomes. Due to the variability in the studies, it is impossible to stratify fertility outcomes of surgery by the localization of deep endometriosis. More investigations are needed to determine whether surgical management should be first-intention or limited to the failure of medically assisted reproduction treatment.

Current status and challenges of drug development for hormonal treatment of endometriosis: a systematic review of randomized control trials

OBJECTIVE

The aim of this systematic review is to summarize the data obtained from randomized controlled trials looking at new pharmacologic treatments for endometriosis published over the last decade with a focus on hormonal therapeutic options for endometriosis-associated pelvic pain (EAPP), excluding studies focusing on fertility.

METHODS

We identified relevant original studies in the English language through a search of the MEDLINE, Scopus, and EMBASE (2012 to present) databases using the appropriate MeSH terms and applying the article type filter 'randomized controlled trials'. A total of 219 records were found during the electronic search. After a detailed evaluation and review of the manuscripts, 11 primary articles met the inclusion criteria. A systematic review of the data was conducted.

RESULTS

This review included several emerging drug therapies for EAPP. Randomized control trials showed promising results with several oral gonadotropin-releasing hormone antagonists (elagolix, relugolix, ASP1707, linzagolix). However, studies of other hormonal agents such as aromatase inhibitors and selective progesterone receptor modulators have not yielded significant or new advantages. Selective estrogen receptor modulators have not been represented in randomized control trials and have failed to demonstrate clinical efficacy.

CONCLUSION

Although numerous novel agents are being investigated for the treatment of endometriosis, there is still no significant progress in the development of curative rather than suppressive drugs. Therefore, further efforts are needed to develop an effective and hopefully curative treatment for this chronic, costly, and overwhelming disease.

Concurrent Benign Metastasizing Leiomyoma in the Abdominal Wall and Pelvic Cavity: A Case Report and Review of the Literature

Benign metastatic leiomyoma (BML) is a histologically benign disease with invasive biological behavior. Most patients are women of childbearing age with a history of uterine leiomyoma. The progress of the disease is relatively slow, the prognosis is good, and most patients can survive for a long time. The lung is the common metastatic site, and BML with metastatic lesions outside the lung is very rare. A 37-year-old woman with multiple BML in the abdominal wall and pelvic cavity after uterine leiomyoma surgery was admitted to our hospital. Combined with the clinical data of this case and reviewing the relevant literature, this paper discusses the pathological characteristics, diagnosis, differential diagnosis, and treatment of BML.

Characterization of patients that can continue conservative treatment for adenomyosis

Background

Historically, hysterectomy has been the radical treatment for adenomyosis. Although, some patients may not want to have their uterus removed, patients often have to no choice but to request hysterectomy during conservative treatment. The factors necessitating these hysterectomies remain unknown. The purpose of this study was to determine which patients can continue conservative treatment for adenomyosis.

Methods

We selected women diagnosed with adenomyosis and provided with conservative treatment at the Kindai University Hospital and Osaka Red Cross Hospital in Osaka Japan from 2008 to 2017. Age at diagnosis, parity, uterine size, subtype of adenomyosis, type of conservative treatment, and timing of hysterectomy for cases with difficulty continuing conservative treatment were examined retrospectively.

Results

A total of 885 patients were diagnosed with adenomyosis, and 124 started conservative treatment. Conservative treatment was continued in 96 patients (77.4%) and hysterectomy was required in 28 patients (22.6%). The cumulative hysterectomy rate was 32.4%, and all women had hysterectomy within 63 months. In the classification tree, 82% (23/28) of women aged 46 years or younger were able to continue conservative treatment when parity was zero or one. In those with parity two and over, 95% (20/21) of those aged 39 years and older had hysterectomy.

Conclusions

Patients who continue conservative treatment for approximately 5 years are more likely to have successful preservation of the uterus. Multiparity and higher age at diagnosis are factors that contribute to hysterectomy after conservative treatment. Parity and age at diagnosis may be stratifying factors in future clinical trials of hormone therapy.

Possible role of microbiome in the pathogenesis of endometriosis

INTRODUCTION

There is an urgent necessity to explore the complex pathophysiological nature of endometriosis, which may enable the rationale for new diagnostic and therapeutic strategies to be discovered. This systematic review aimed to clarify the bidirectional relationship between endometriosis and the microbiome and evaluate if the microbiome may be involved in endometriosis's pathogenesis, establishing a potential connection between the different studies.

EVIDENCE ACQUISITION

Studies were identified through a systematic literature search of papers that evaluated the microbiomes of human or other animal species with endometriosis and of those without in the electronic database PubMed/Medline, and Embase without a date restriction. We included all cohort studies focusing on the interaction between endometriosis and the microbiomes of humans or other mammals, evaluating if the microbiome may be involved in endometriosis's pathogenesis.

EVIDENCE SYNTHESIS

Endometriosis appears to be associated with elevated levels of different microorganisms across various microbiome sites. An ineffective immune response seems to play a key role in endometriosis pathogenesis, and there is some scientific proof to state that the immune response may be modulated by the microbiome. Interestingly, nine studies of our review detected species belonging to the phyla Proteobacteria, Bacteroidetes, and Negativicutes characterized by Gram-negative staining, that were significantly increased in endometriosis cohorts.

CONCLUSIONS

Laboratory and clinical investigations indicate that hosts' microbiome profiles with and without endometriosis can be significantly different. To further our understanding of the relationships between endometriosis and the host microbiome, more studies are necessary.

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.

Management Challenges of Deep Infiltrating Endometriosis

Deep infiltrating endometriosis (DIE) is the most aggressive of the three phenotypes that constitute endometriosis. It can affect the whole pelvis, subverting the anatomy and functionality of vital organs, with an important negative impact on the patient's quality of life. The diagnosis of DIE is based on clinical and physical examination, instrumental examination, and, if surgery is needed, the identification and biopsy of lesions. The choice of the best therapeutic approach for women with DIE is often challenging. Therapeutic options include medical and surgical treatment, and the decision should be dictated by the patient's medical history, disease stage, symptom severity, and personal choice. Medical therapy can control the symptoms and stop the development of pathology, keeping in mind the side effects derived from a long-term treatment and the risk of recurrence once suspended. Surgical treatment should be proposed only when it is strictly necessary (failed hormone therapy, contraindications to hormone treatment, severity of symptoms, infertility), preferring, whenever possible, a conservative approach performed by a multidisciplinary team. All therapeutic possibilities have to be explained by the physicians in order to help the patients to make the right choice and minimize the impact of the disease on their lives.

Recent developments in pharmaceutical salts: FDA approvals from 2015 to 2019

Around half of the new molecular entities approved by the US Food and Drug Administration (FDA) are pharmaceutical salts. The pharmaceutical salts have been on a continuous growth trajectory since the approval of the first salt form in 1939. This review aims to provide updates on pharmaceutical salts approved by the FDA between 2015 and 2019. The five-year drug-approval database contains 61 pharmaceutical salts, featuring a diverse range of counterions; however, hydrochlorides are the most abundant. The chemical structures of all pharmaceutical salts in each class are presented here, along with their therapeutic indications and date of approval. The reason behind the selection of a particular counterion and the technical superiority achieved by the salt form over the free active pharmaceutical ingredient base are also discussed.

Medical therapy options for endometriosis related pain, which is better? A systematic review and network meta-analysis of randomized controlled trials

Our objective was to assess and rank different pharmacological interventions for relieving endometriosis-related pain. We conducted an online bibliographic search in different databases from their inception until March 2019. We included randomized controlled trials (RCTs) that assessed different medical therapies in the management of endometriosis-related pain. We applied this network meta-analysis (NMA) based on the frequentist approach using statistical package "netmeta" (version 1.0-1) in R software. Our main outcomes were the change in severity of pelvic pain, dysmenorrhea score, non-menstrual pelvic pain score, and dyspareunia score. Overall, 36 RCTs were included in this study (patients no. = 7942). Dienogest (0.94), combined hormonal contraceptives (CHCs) (0.782), and elagolix (0.38) were the highest-ranked interventions for reducing the severity of pelvic pain at three months, while at six months, gonadotropin-releasing hormone (GnRH) analogues (0.75), levonorgestrel-releasing intrauterine system (LNG-IUS) (0.73), and dienogest (0.65) were linked to more reduction in pelvic pain. The ranking p-score showed that GnRH analogues was the highest-ranked treatment for reducing dysmenorrhea at 3 months (1.00), while CHCs were the highest-ranked treatment at 6 months (0.97), followed by GnRH analogues (0.89). GnRH analogues (0.63) and elagolix (0.54) at three months while desogestrel (0.94) and CHCs (0.91) at six months were the highest-ranked treatment to reduce non-menstrual pelvic pain. GnRH analogues and elagolix were the highest-ranked pharmacologic therapies for reducing dyspareunia. In conclusion, CHCs, GnRH analogues, progesterone, and elagolix were the best approaches in reducing the pain of endometriosis.

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.

Endometriosis

Pelvic endometriosis is a complex syndrome characterized by an estrogen-dependent chronic inflammatory process that affects primarily pelvic tissues, including the ovaries. It is caused when shed endometrial tissue travels retrograde into the lower abdominal cavity. Endometriosis is the most common cause of chronic pelvic pain in women and is associated with infertility. The underlying pathologic mechanisms in the intracavitary endometrium and extrauterine endometriotic tissue involve defectively programmed endometrial mesenchymal progenitor/stem cells. Although endometriotic stromal cells, which compose the bulk of endometriotic lesions, do not carry somatic mutations, they demonstrate specific epigenetic abnormalities that alter expression of key transcription factors. For example, GATA-binding factor-6 overexpression transforms an endometrial stromal cell to an endometriotic phenotype, and steroidogenic factor-1 overexpression causes excessive production of estrogen, which drives inflammation via pathologically high levels of estrogen receptor-β. Progesterone receptor deficiency causes progesterone resistance. Populations of endometrial and endometriotic epithelial cells also harbor multiple cancer driver mutations, such as KRAS, which may be associated with the establishment of pelvic endometriosis or ovarian cancer. It is not known how interactions between epigenomically defective stromal cells and the mutated genes in epithelial cells contribute to the pathogenesis of endometriosis. Endometriosis-associated pelvic pain is managed by suppression of ovulatory menses and estrogen production, cyclooxygenase inhibitors, and surgical removal of pelvic lesions, and in vitro fertilization is frequently used to overcome infertility. Although novel targeted treatments are becoming available, as endometriosis pathophysiology is better understood, preventive approaches such as long-term ovulation suppression may play a critical role in the future.

New insights on the pathogenesis of endometriosis and novel non-surgical therapies

Endometriosis is a disease of theories, but none has succeeded to explain the whole picture. Most widely available drugs for endometriosis aim to relieve symptoms and improve fertility. Unfortunately, many short and long-term side-effects are associated with the treatments. To overcome this problem, researchers have developed many novel therapeutic agents, including non-invasive technique. We aim to provide new insights on pathogenesis model and novel non-surgical treatments for endometriosis, including drugs already available in the market and also drugs which are still under research. Seven novel treatment modalities are recognized, namely dienogest, aromatase inhibitor (AI), gonadotrophine-releasing hormone (GnRH) antagonist, anti tumor necrosing factor (TNF)-α, selective estrogen receptor modulator (SERM), selective progesterone receptor modulator (SPRM), and high-intensity focused ultrasound (HIFU). Dienogest, AI, and GnRH antagonists are effective novel treatments with good tolerance and safety. SERM and SPRM show inconsistent results, while anti-TNF-α is still in the animal experimental stage. HIFU is a potential futuristic treatment. However, it is still a long way until this technology is truly applicable.

Synthesis and biological evaluation of 3-(2-aminoethyl) uracil derivatives as gonadotropin-releasing hormone (GnRH) receptor antagonists

We investigated a series of uracil analogues by introducing various substituents on the phenyl ring of the N-3 aminoethyl side chain and evaluated their antagonistic activity against human gonadotropin-releasing hormone (GnRH) receptors. Analogues with substituents at the ortho or meta position demonstrated potent in vitro antagonistic activity. Specifically, the introduction of a 2-OMe group enhanced nuclear factor of activated T-cells (NFAT) inhibition up to 6-fold compared to the unsubstituted analogue. We identified compound 12c as a highly potent GnRH antagonist with moderate CYP inhibition. Compound 12c showed potent and prolonged LH suppression after a single dose was orally administered in castrated monkeys compared to a known antagonist, Elagolix. We believe that our SAR study offers useful insights to design GnRH antagonists as a potential treatment option for endometriosis.

Recent Development of Non-Peptide GnRH Antagonists

The decapeptide gonadotropin-releasing hormone, also referred to as luteinizing hormone-releasing hormone with the sequence (pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH₂) plays an important role in regulating the reproductive system. It stimulates differential release of the gonadotropins FSH and LH from pituitary tissue. To date, treatment of hormone-dependent diseases targeting the GnRH receptor, including peptide GnRH agonist and antagonists are now available on the market. The inherited issues associate with peptide agonists and antagonists have however, led to significant interest in developing orally active, small molecule, non-peptide antagonists. In this review, we will summarize all developed small molecule GnRH antagonists along with the most recent clinical data and therapeutic applications.

Adverse bone effects of medications used to treat non-skeletal disorders

There is a growing list of medications used to treat non-skeletal disorders that cause bone loss and/or increase fracture risk. This review discusses glucocorticoids, drugs that reduce sex steroids, antidiabetic agents, acid-reducing drugs, selective serotonin reuptake inhibitors, and heparin. A number of drugs are known to cause bone loss, increase fracture risk, or both. These drugs should be used in the lowest dose necessary to achieve the desired benefit and for the shortest time necessary, but in many cases, long-term treatment is required. Effective countermeasures are available for some.

Research development of a new GnRH antagonist (Elagolix) for the treatment of endometriosis: a review of the literature

PURPOSE

Limitated studies have reported the efficacy of GnRH antagonist on endometriosis symptoms. The aim of our study was to review all available trials to investigate the medical treatment of endometriosis with only GnRH antagonists, with special attention to pharmacodynamic activity, safety, and efficacy.

METHODS

Pub Med and Sciencedirect database were searched using terms of "endometriosis treatment", "GnRH antagonist", and "Elagolix". The search was limited to clinical studies published in English. Title and abstract were screened to identify relevant articles.

RESULTS

Five studies covering use of GnRH antagonist were found. A phase 1 study evaluated the safety, pharmacokinetics, and inhibitory effects on gonadotropins and estradiol of single dose and 7 day elagolix administration to healthy premenopausal women; two phase II studies evaluated efficacy in patient with endometriosis. Moreover, there are two Phase III clinical trials just completed.

CONCLUSION

GnRH antagonists may have the advantage of oral administration and lower incidence of adverse events. Currently, only Phase II studies have been published demonstrating promising results in terms of efficacy, safety, and tolerability. From the results of the phase III studies, elagolix may become a valuable addition to the armamentarium of pharmacological agents to treat endometriosis-related pain.

New developments in the medical treatment of endometriosis

Endometriosis affects 1 in 10 women of reproductive-age. The current treatments are surgical and hormonal but have limitations, including the risk of recurrence, side effects, contraceptive action for women who desire pregnancy, and cost. New treatments include gonadotropin-releasing hormone analogues, selective progesterone (or estrogen) receptor modulators, aromatase inhibitors, immunomodulators, and antiangiogenic agents. Further research is needed into central sensitization, local neurogenesis, and the genetics of endometriosis to identify additional treatment targets. A wider range of medical options allows for the possibility of precision health and a more personalized treatment approach for women with endometriosis.

Pharmacologic treatment of the ovarian endometrioma

INTRODUCTION

Treatment of ovarian endometriomas is commonly achieved through laparoscopic surgery and this can be effective in eliminating the disease, although a majority of recent trials documented an adverse effect of surgery on ovarian reserve markers. With the advancement in imaging techniques, ovarian endometriomas are increasingly diagnosed at an earlier stage when the endometrioma may be smaller, less fibrotic and more responsive to medical treatment, making an evaluation of medical options critically important.

AREAS COVERED

The review focuses on currently utilized pharmacologic therapies for endometrioma (oral contraceptives, the levonorgestrel-releasing IUS, the hormone-releasing subdermal implant, Implanon); experimental and future treatments are also mentioned (GnRH antagonists, progesterone receptor modulators, antioestrogens, newer subdermal implants and intracystic administration of pharmacologic agents). Finally, the usefulness of post-operative adjuvant medical treatments is discussed Expert opinion: Today, reliable, non-invasive diagnostic procedures of an ovarian endometrioma are available and should be utilized to identify its presence and type of pathology. In a young patient, classic medical therapies such as oral contraceptives and synthetic progestins should be tried first to alleviate symptoms. Only when these regimens fail, should a minimally invasive surgery be envisaged. Following endoscopic surgery, adjuvant medical treatment may reduce recurrence of both symptoms and the lesion.