Elagolix Suppresses Ovulation in a Dose-Dependent Manner: Results From a 3-Month, Randomized Study in Ovulatory Women

The modern management of uterine fibroids-related abnormal uterine bleeding

Uterine fibroids (UFs) are the most common female benign pelvic tumors, affecting >60% of patients aged 30-44 years. Uterine fibroids are asymptomatic in a large percentage of cases and may be identified incidentally using a transvaginal ultrasound or a magnetic resonance imaging scan. However, in approximately 30% of cases, UFs affect the quality of life and women's health, with abnormal uterine bleeding and heavy menstrual bleeding being the most common complaints, along with iron deficiency (ID) and ID anemia. Medical treatments used for UFs-related abnormal uterine bleeding include symptomatic agents, such as nonsteroidal antiinflammatory drugs and tranexamic acid, and hormonal therapies, including combined oral contraceptives, gonadotropin-releasing hormone agonists or antagonists, levonorgestrel intrauterine systems, selective progesterone receptor modulators, and aromatase inhibitors. Nevertheless, few drugs are approved specifically for UF treatment, and most of them manage the symptoms. Surgical options include fertility-sparing treatments, such as myomectomy, or nonconservative options, such as hysterectomy, especially in perimenopausal women who are not responding to any treatment. Radiologic interventions are also available: uterine artery embolization, high-intensity focused ultrasound or magnetic resonance-guided focused ultrasound, and radiofrequency ablation. Furthermore, the management of ID and ID anemia, as a consequence of acute and chronic bleeding, should be taken into account with the use of iron replacement therapy both during medical treatment and before and after a surgical procedure. In the case of symptomatic UFs, the location, size, multiple UFs, or coexistent adenomyosis should guide the choice with a shared decision-making process, considering long- and short-term treatment goals expected by the patient, including pregnancy desire or wish to preserve the uterus independently of reproductive goals.

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.

Oral Gonadotropin-Releasing Hormone Antagonists for the Treatment of Uterine Leiomyomas

Uterine leiomyomas are common hormone-responsive neoplasms that frequently cause heavy menstrual bleeding, anemia, pelvic pressure, pain, and adverse reproductive outcomes. In this overview, the efficacy and safety of oral gonadotropin-releasing hormone (GnRH) antagonists, co-administered with menopausal replacement-level steroid hormones or used at doses to avoid complete hypothalamic suppression, are reviewed for the management of uterine leiomyomas. Oral GnRH antagonists provide rapid suppression of sex steroids and avoid the initial steroidal flare and resultant temporary worsening of symptoms typically seen with parenteral GnRH agonists. Oral GnRH antagonists are effective in reducing leiomyoma-associated heavy menstrual bleeding, with high rates of amenorrhea and improved anemia and leiomyoma-associated pain, and providing modest reduction in uterine volume when used in combination with menopausal replacement-level steroid hormones. This add-back therapy can reduce hypogonadal side effects, including hot flushes and bone mineral density loss, close to levels seen with placebo therapy. Currently, both elagolix 300 mg twice daily with once-daily estradiol (1 mg) and norethindrone (0.5 mg) and relugolix 40 mg once daily with estradiol (1 mg) and norethindrone (0.5 mg) combination therapy are approved for leiomyoma treatment by the U.S. Food and Drug Administration. Linzagolix is under investigation in the United States but approved at two does with and without steroid hormones in the European Union. The efficacy of these agents appears to be robust over a wide spectrum of clinical presentations, demonstrating that worse disease parameters at baseline do not appear to inhibit efficacy. Across clinical trials, participants largely reflected the population of individuals affected by uterine leiomyomas.

Infertility workup: identifying endometriosis

Endometriosis was classically diagnosed during diagnostic laparoscopies, which used to be routinely performed up until a decade ago or so. This practice fitted with the long-held belief that surgery was the gold standard for diagnosing endometriosis. Today, the abandon of routine diagnostic laparoscopies-in favor of assisted reproductive technology-first therapeutic approaches-has created a void for diagnosing endometriosis. Modern-day imaging techniques-ultrasound and magnetic resonance imaging-when used with a systematic approach have offered a reliable replacement option for diagnosing endometriosis. In infertility, endometriosis should be identified or excluded on the basis of past history or confirmation or exclusion suspicion on the basis of history and/or physical examination.

Does timing matter when initiating elagolix in a natural menstrual cycle?

Objective

To investigate the efficacy of elagolix when administered at different time points in a menstrual cycle.

Design

Clinical case series.

Setting

Academic reproductive endocrinology center.

Patients

Ovulatory women not desiring pregnancy.

Intervention(s)

Six doses of elagolix 200 mg were administered over 4 days, starting at 3 different points in a menstrual cycle: early follicular; late follicular; and midluteal. Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and progesterone (P) concentrations were measured at baseline, during elagolix administration, and 1 day after the last dose. Transvaginal ultrasounds were performed to monitor follicle sizes.

Main Outcome Measure(s)

Serum FSH, LH, E2, and P.

Result(s)

Twelve women, four per group, completed the study. Subjects were 23–42 years of age. Demographics and ovarian reserve parameters were similar among participants. Elagolix suppressed FSH, LH, E2, and P when administered in the early follicular and midluteal phases but had mixed results when administered in the late follicular phase. Two participants demonstrated suppression of all four hormones. One participant ovulated, indicated by an increase in P concentration and development of a corpus luteum. A second participant did not ovulate yet demonstrated an increase in E2 concentration with growth of a dominant follicle. There were no significant differences in median percent change of hormone concentrations across study groups.

Conclusion(s)

The results of this study suggest that elagolix can suppress the hypothalamic–pituitary–ovarian axis when initiated at different points in a menstrual cycle. Optimal dosing and treatment window for consistent hormone suppression have yet to be determined.

Clinical Registration Number

NCT04060992

Oriahnn: New Drug Approved for Treating Heavy Menstrual Bleeding in Women With Uterine Fibroids

OBJECTIVE

To review data of elagolix plus estradiol and norethindrone acetate as add-back therapy for the treatment of heavy menstrual bleeding (HMB) in premenopausal women with uterine fibroids.

DATA SOURCES

Literature search of PubMed/MEDLINE and SCOPUS was performed using the search terms Oriahnn; elagolix, estradiol, norethindrone AND heavy menstrual bleeding; elagolix AND heavy menstrual bleeding; and gonadotropin-releasing hormone receptor antagonist AND heavy menstrual bleeding between January 1, 1996, to March 2, 2021. Additional data were obtained from prescribing information, references of identified articles, and abstracts from scientific meetings.

STUDY SELECTION/DATA EXTRACTION

Clinical trials and articles discussing elagolix plus add-back therapy for the management of HMB in women with leiomyomas were included.

DATA SYNTHESIS

Phase 3 trials met the primary end point of menstrual blood loss (MBL) less than 80 mL at month 6 and at least a 50% reduction in MBL from baseline to the final month in 68.5% of women taking elagolix plus add-back therapy enrolled in UF-1 (8.7% placebo) and 76.5% of women in UF-2 (10% placebo). The most common adverse effects include hot flushes, nausea, headache, and night sweats.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Women with symptomatic uterine fibroids can experience significant HMB resulting in distress, depression, and anxiety. Surgical intervention remains the most commonly recommended and chosen treatment. Elagolix plus add-back therapy is a nonsurgical, oral option.

CONCLUSIONS

Elagolix plus add-back therapy is effective in reducing menstrual bleeding associated with uterine fibroids. However, there are several warnings and precautions that must be considered.

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.

Pharmacokinetic and Pharmacodynamic Profiles of Ethinylestradiol/Norgestimate Combination or Norethindrone upon Coadministration with Elagolix 150 mg Once Daily in Healthy Premenopausal Women

Background

Two pharmacokinetic/pharmacodynamic studies were conducted to evaluate the potential drug–drug interaction between elagolix, an oral gonadotropin-releasing hormone receptor antagonist, and an oral contraceptive (ethinylestradiol [EE] 0.035 mg and norgestimate 0.18/0.215/0.25 mg) or progestin-only contraceptive (norethindrone 0.35 mg) in healthy premenopausal women.

Methods

These phase I studies used a two-period, sequential design, where period 1 included treatment with oral contraceptives, followed by period 2 with contraceptives coadministered with elagolix 150 mg once daily.

Results

In study 1, pharmacokinetic exposures for EE in period 2 increased by 30% and the norgestimate metabolites decreased by approximately 15% when coadministered with elagolix. Mean hormone exposure appeared lower for follicle-stimulating hormone (FSH; 31%), luteinizing hormone (LH; 38%), and estradiol (E2; 16%). The percentage of women with consecutive progesterone (P) concentrations above 5 nmol/L was similar in both periods. Norethindrone pharmacokinetic exposures were comparable in both periods. The hormone exposure for LH and FSH was similar, and mean E2 exposure was 32% lower in period 2. The percentage of subjects with consecutive ovulatory P concentrations was also similar in both periods (study 2). Safety and tolerability profiles were unremarkable in both studies.

Conclusions

Coadministration of elagolix 150 mg once daily with oral contraceptives containing EE and norgestimate, or norethindrone, resulted in small pharmacokinetic changes in the oral contraceptive components. Similar or lower FSH, LH, and E2 exposures were observed during coadministration, with ovulatory P concentrations also comparable in both periods. The pharmacodynamic profiles of the oral contraceptives were maintained when coadministered with elagolix.

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.

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.

Assessment of Clinical Drug-Drug Interactions of Elagolix, a Gonadotropin-Releasing Hormone Receptor Antagonist

Elagolix is an oral gonadotropin-releasing hormone receptor antagonist indicated for the management of endometriosis-associated pain and in combination with estradiol/norethindrone acetate indicated for the management of heavy menstrual bleeding associated with uterine leiomyomas (fibroids) in premenopausal women. Elagolix coadministered with estradiol/norethindrone acetate is in late-stage development for the management of heavy menstrual bleeding associated with uterine fibroids. Based on the in vitro profile of elagolix metabolism and disposition, 9 drug-drug interaction (DDI) studies evaluating the victim and perpetrator characteristics of elagolix were conducted in 144 healthy volunteers. As a victim of cytochrome P450 (CYPs) and transporter-mediated DDIs, elagolix area under the curve (AUC) increased by ∼2-fold following coadministration with ketoconazole and by ∼5- and ∼2-fold with single and multiple doses of rifampin, respectively. As a perpetrator, elagolix decreased midazolam AUC (90% confidence interval) by 54% (50%-59%) and increased digoxin AUC by 32% (23%-41%). Elagolix decreased rosuvastatin AUC by 40% (29%-50%). No clinically significant changes in exposure on coadministration with sertraline or fluconazole occurred. A elagolix 150-mg once-daily regimen should be limited to 6 months with strong CYP3A inhibitors and rifampin because of the potential increase in bone mineral density loss, as described in the drug label. A 200-mg twice-daily regimen is recommended for no more than 1 month with strong CYP3A inhibitors and not recommended with rifampin. Elagolix is contraindicated with strong organic anion transporter polypeptide B1 inhibitors (eg, cyclosporine and gemfibrozil). Consider increasing the doses of midazolam and rosuvastatin when coadministered with elagolix, and individualize therapy based on patient response. Clinical monitoring is recommended for P-glycoprotein substrates with a narrow therapeutic window (eg, digoxin). Dose adjustments are not required for sertraline, fluconazole, bupropion (or any CYP2B6 substrate), or elagolix when coadministered.

Effect of Elagolix Exposure on Clinical Efficacy End Points in Phase III Trials in Women With Endometriosis-Associated Pain: An Application of Markov Model

Elagolix is an oral gonadotropin‐releasing hormone antagonist approved by the US Food and Drug Administration (FDA) for the management of moderate‐to‐severe pain associated with endometriosis and in combination with estradiol/norethindrone acetate approved for the management of heavy menstrual bleeding associated with uterine leiomyomas (fibroids) in premenopausal women. The objective of this work was to characterize the relationships between elagolix exposures and clinical efficacy response rates for dysmenorrhea (DYS) and nonmenstrual pelvic pain (NMPP) in premenopausal women enrolled in the pivotal phase III studies with moderate‐to‐severe pain associated with endometriosis. Relationships between elagolix average concentrations (C_avg) and efficacy responses (DYS and NMPP) were characterized using a nonlinear mixed‐effects discrete‐time first order Markov modeling approach. Only age was statistically significant for NMPP but not considered clinically relevant. This work indicates that the selection of elagolix dose is not determined based on tested patient demographics, baseline, or endometriosis disease severity measures in covariate analysis. In other words, the work suggests no preference of one regimen over the other to treat endometriosis‐associated pain (DYS or NMPP) for any patient subpopulation based on tested covariate groups.

Clinical characteristics difference between early and late recurrence of ovarian endometriosis after laparoscopic cystectomy

BACKGROUND

Ovarian endometriosis is the most frequent type of endometriosis. Despite the use of surgery and medication, many patients suffer from recurrence within near future. Currently, there are no effective clinical characteristics available to predict the time to recurrence in ovarian endometriosis patients.

PURPOSE

To identify the effective clinical indicators for early and late endometrioma recurrence, we compared the clinical characteristics of early and late recurrence after treatment.

METHODS

We collected 358 patients with ovarian endometriosis who had a minimum of 5 years of postoperative follow-up after undergoing a laparoscopic excision of ovarian endometrioma performed at Peking Union Medical College Hospital from January 2009 to April 2013.

RESULTS

A total of 358 patients were recruited in the validation set, with a median follow-up time of 83 months (60-120 months). Till the last follow-up, 68 patients exhibited recurrence. Three-year and 5-year recurrence rates were 9.2% and 15.4%, respectively. Univariate analysis in our study showed that patient with endometrioma surgery history had higher incidence of recurrence in 3 years after re-surgery (OR: 5.594, P = 0.029). Univariate and multivariate analyses using the logistic regression showed that the presence of tenesmus before surgery affected the incidence of early recurrence with a ratio of 57.9% (11/19) and 89.5% (17/19) in 3 years and 5 years after surgery, respectively.

CONCLUSIONS

Presence of tenesmus before surgery may be linked to the early recurrence of endometrioma.

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.