T0901317, an Agonist of Liver X Receptors, Attenuates Neuronal Apoptosis in Early Brain Injury after Subarachnoid Hemorrhage in Rats via Liver X Receptors/Interferon Regulatory Factor/P53 Upregulated Modulator of Apoptosis/Dynamin-1-Like Protein Pathway.

METHODS: Subarachnoid hemorrhage (SAH) models of Sprague-Dawley rats were established with perforation method. T0901317 was injected intraperitoneally 1-hour post-SAH. GSK2033, an inhibitor of LXRs, and interferon regulatory factor (IRF-1) CRISPR activation were injected intracerebroventricularly to evaluate potential signaling pathway. The severity of SAH, neurobehavior test in both short- and long-term and apoptosis was measured with Western blot and immunofluorescence staining. RESULTS: Expression of LXR-α and IRF-1 increased and peaked at 24 h post-SAH, while LXR-ß remained unaffected in SAH+vehicle group compared with Sham group. Post-SAH T0901317 treatment attenuated neuronal impairments in both short- and long-term and decreased neuronal apoptosis, the expression of IRF-1, P53 upregulated modulator of apoptosis (PUMA), dynamin-1-like protein (Drp1), Bcl-2-associated X protein (Bax) and cleaved caspase-3, and increasing B-cell lymphoma 2 (Bcl-2) at 24 h from modeling. GSK2033 inhibited LXRs and reversed T0901317's neuroprotective effects. IRF-1 CRISPR activation upregulated the expression of IRF-1 and abolished the treatment effects of T0901317. CONCLUSION: T0901317 attenuated neuronal apoptosis via LXRs/IRF-1/PUMA/Drp1 pathway in SAH rats.

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.

Synthesis and evaluation of novel fluorinated hematoporphyrin ether derivatives for photodynamic therapy.

A photosensitizer with high phototoxicity, suitable amphipathy and low dark toxicity could play a pivotal role in photodynamic therapy (PDT). In this study, a facile and versatile approach was adopted to synthesize a series of novel fluorinated hematoporphyrin ether derivatives (I1-I5 and II1-II4), and the photodynamic activities of these compounds were studied. Compared to hematoporphyrin monomethyl ether (HMME), all PSs showed preferable photodynamic activity against A549 lung tumor cells. The longest visible absorption wavelength of these compounds was approximately 622 nm. Among them, II3 revealed the highest singlet oxygen yield (0.0957 min-1), the strongest phototoxicity (IC50 = 1.24 µM), the lowest dark toxicity in vitro, and exhibited excellent anti-tumor effects in vivo. So compound II3 could act as new drug candidate for photodynamic therapy.

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.

A Clinician's Guide to the Treatment of Endometriosis with Elagolix.

Pain associated with endometriosis is a considerable burden for women, permeating all aspects of their lives, from their ability to perform daily activities to their quality of life. Although there are many options for endometriosis-associated pain management, they are often limited by insufficient efficacy, inconvenient routes of administration, and/or intolerable side effects. Elagolix, a nonpeptide, small-molecule gonadotropin-releasing hormone (GnRH) receptor antagonist, is the first new oral therapy to be approved for the treatment of endometriosis-associated pain in the United States in more than a decade. Modulation of estradiol with elagolix is dose dependent and ranges from partial to full suppression. Clinical evidence has shown that elagolix at both approved doses (150 mg once daily and 200 mg twice daily) is effective for reducing symptoms of pelvic pain (dysmenorrhea, nonmenstrual pelvic pain, and dyspareunia), improving quality of life, and decreasing use of rescue analgesics (nonsteroidal anti-inflammatory drugs and/or opioids). The availability of two dosing options allows for individualization of treatment based on baseline clinical factors and response to therapy. Elagolix is well tolerated, with less pronounced hypoestrogenic effects compared with GnRH agonists. This review provides an overview of elagolix, highlighting currently available treatment options and the application of this new treatment for women with endometriosis-associated pain.

Exposure-Safety Analyses Identify Predictors of Change in Bone Mineral Density and Support Elagolix Labeling for Endometriosis-Associated Pain.

Elagolix is a novel oral gonadotropin releasing hormone receptor antagonist, that can suppress estradiol in a dose-dependent manner. It is indicated for management of moderate-to-severe pain associated with endometriosis. A population exposure-response model describing the relationship between elagolix exposure and changes in bone mineral density (BMD) was developed using data from four phase III studies in premenopausal women with endometriosis-associated pain. Elagolix pharmacokinetic exposure-dependent changes in BMD were described by an indirect-response maximum effect (Emax ) model through stimulation of bone resorption. African American race, higher body mass index (BMI), and lower type-I collagen C-telopeptide concentrations were significantly associated with higher baseline BMD. Higher BMI was significantly associated with higher bone formation rates. Simulations using the final model demonstrated that elagolix 150 mg q.d. dosing for 24 months is predicted to result in -1.45% (-2.04 to -0.814) decrease from baseline in BMD and were used to support corresponding dosing recommendations in the label.

Clinical Conundrum: A 33-Year-Old With Pain Post-Orgasm and a History of Endometriosis.

A 33-year-old with a history of endometriosis presented with pain post-orgasm, accompanied by breakthrough bleeding, nausea, sweatiness, and exhaustion. History and examination suggested a gynaecologic component, likely related to the uterus itself. After several therapeutic trials, a clinical response was obtained with the use of a gonadotropin-releasing hormone antagonist, elagolix. The case is discussed with respect to dysorgasmia and post-orgasm illness syndrome. Post-orgasm pain in women has not been well studied, and it is recommended that such periorgasm phenomena be the topic of future research.

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.

Elagolix for Heavy Menstrual Bleeding in Women with Uterine Fibroids.

BACKGROUND: Uterine fibroids are hormone-responsive neoplasms that are associated with heavy menstrual bleeding. Elagolix, an oral gonadotropin-releasing hormone antagonist resulting in rapid, reversible suppression of ovarian sex hormones, may reduce fibroid-associated bleeding. METHODS: We conducted two identical, double-blind, randomized, placebo-controlled, 6-month phase 3 trials (Elaris Uterine Fibroids 1 and 2 [UF-1 and UF-2]) to evaluate the efficacy and safety of elagolix at a dose of 300 mg twice daily with hormonal "add-back" therapy (to replace reduced levels of endogenous hormones; in this case, estradiol, 1 mg, and norethindrone acetate, 0.5 mg, once daily) in women with fibroid-associated bleeding. An elagolix-alone group was included to assess the impact of add-back therapy on the hypoestrogenic effects of elagolix. The primary end point was menstrual blood loss of less than 80 ml during the final month of treatment and at least a 50% reduction in menstrual blood loss from baseline to the final month; missing data were imputed with the use of multiple imputation. RESULTS: A total of 412 women in UF-1 and 378 women in UF-2 underwent randomization, received elagolix or placebo, and were included in the analyses. Criteria for the primary end point were met in 68.5% of 206 women in UF-1 and in 76.5% of 189 women in UF-2 who received elagolix plus add-back therapy, as compared with 8.7% of 102 women and 10% of 94 women, respectively, who received placebo (P<0.001 for both trials). Among the women who received elagolix alone, the primary end point was met in 84.1% of 104 women in UF-1 and in 77% of 95 women in UF-2. Hot flushes (in both trials) and metrorrhagia (in UF-1) occurred significantly more commonly with elagolix plus add-back therapy than with placebo. Hypoestrogenic effects of elagolix, especially decreases in bone mineral density, were attenuated with add-back therapy. CONCLUSIONS: Elagolix with add-back therapy was effective in reducing heavy menstrual bleeding in women with uterine fibroids. (Funded by AbbVie; Elaris UF-1 and Elaris UF-2 ClinicalTrials.gov numbers, NCT02654054 and NCT02691494.).

Achieving clinically meaningful response in endometriosis pain symptoms is associated with improvements in health-related quality of life and work productivity: analysis of 2 phase III clinical trials.

BACKGROUND: Endometriosis-related pain symptoms have a negative impact on health-related quality of life and productivity. In fact, as endometriosis-related symptom severity and the number of symptoms experienced increases, health-related quality of life decreases. Dysmenorrhea and nonmenstrual pelvic pain are prominent symptoms experienced by women with endometriosis and were shown to have improved with the oral, nonpeptide gonadotropin-releasing hormone antagonist, elagolix. OBJECTIVE: The objective of this post hoc analysis was to address the question of if patients show a clinical response (in dysmenorrhea or nonmenstrual pelvic pain), do they also have improvements in health-related quality of life and in productivity? STUDY DESIGN: This post hoc analysis used data from the Elaris Endometriosis-I and Elaris Endometriosis-II phase III, randomized, placebo-controlled studies. A surgical diagnosis of endometriosis (in the past 10 years), premenopausal, aged 18-49 years, and moderate to severe endometriosis-associated pain were among the inclusion criteria for both trials. Women self-reported pain daily using a scale ranging from 0 (no pain) to 3 (severe pain); daily pain was assigned to either dysmenorrhea or nonmenstrual pelvic pain based on self-reported bleeding on that particular day. In addition, their self-reported endometriosis-associated pain must have been an average of moderate or severe during the month leading to baseline for inclusion in the trial program. Patients were characterized as achieving a clinical response for dysmenorrhea or nonmenstrual pelvic pain (ie, responder or nonresponder), which was defined as women who did not have an increase in analgesic use and who met the pain reduction score threshold at month 3. Pain reduction score thresholds were defined separately for dysmenorrhea and nonmenstrual pelvic pain in the trial using receiver-operating characteristics analysis. Health-related quality of life was assessed using the Endometriosis Health Profile-30; work productivity was assessed using the Health-Related Productivity Questionnaire. RESULTS: Women enrolled in Elaris Endometriosis-I (n = 871) and Elaris Endometriosis-II (n = 815) were included in this analysis. Patients with a clinical response during treatment to dysmenorrhea or nonmenstrual pelvic pain also experienced a meaningful improvement in all domains of the Endometriosis Health Profile-30 at month 3. Patients who did not show a dysmenorrhea or nonmenstrual pelvic pain clinical response at month 3 did not exhibit mean improvements in Endometriosis Health Profile-30 domain scores that indicate an Endometriosis Health Profile-30 responder. Productivity improved among dysmenorrhea clinical responders. In the Elaris Endometriosis-I study, clinical responders lost a total of 5.9 hours compared with a total of 13.0 hours for nonresponders of employment-related work at month 3 (P < .0001). Among women in the Elaris Endometriosis-II study, a total of 4.1 hours and 10.4 employment-related hours were lost at month 3 for dysmenorrhea responders vs nonresponders (P < .001). Similar results were obtained when analyzed by non-enstrual pelvic pain responder status. CONCLUSION: Women with moderate to severe endometriosis-related pain, who are clinical responders based on dysmenorrhea and nonmenstrual pelvic pain, also experience significant and clinically meaningful improvement in health-related quality of life and productivity as measured by the Endometriosis Health Profile-30 and Health-Related Productivity Questionnaire, respectively.

Clinical evaluation of the oral gonadotropin-releasing hormone-antagonist elagolix for the management of endometriosis-associated pain.

Endometriosis is an estrogen-dependent chronic inflammatory disease associated with pelvic pain symptoms that are often severe, mainly dysmenorrhea, nonmenstrual pelvic pain and dyspareunia. This condition is also associated with peripheral and central sensitization. The current medical treatment options for endometriosis-associated pain are limited. Recently, the US FDA approved the novel, oral, nonpeptide gonadotropin-releasing hormone antagonist elagolix for the management of moderate to severe endometriosis-associated pain. Elagolix produces dose-dependent estrogen suppression, from partial suppression at lower doses to nearly full suppression at higher doses. This review article summarizes the current understanding of the pathophysiology of endometriosis, with a focus on the role of estrogen and the mechanisms of pain symptoms, and reviews the clinical development of elagolix in women with endometriosis-associated pain.

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.

Impact of elagolix treatment on fatigue experienced by women with moderate to severe pain associated with endometriosis.

OBJECTIVE: To evaluate the efficacy of elagolix, an oral GnRH antagonist, for the reduction of fatigue in women with moderate or severe endometriosis-associated pain. DESIGN: Randomized, double-blind, multicenter, placebo-controlled phase III trial. SETTING: Clinics. PATIENT(S): A total of 860 women treated with elagolix or placebo. INTERVENTION(S): Women received either elagolix at 150 mg daily (QD) orally, elagolix at 200 mg twice daily (BID) orally, or placebo. MAIN OUTCOME MEASURE(S): Change from baseline to month 1, 3, and 6 visits, in Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue Short Form 6a questionnaire T-scores. RESULTS(S): At baseline, 54%-74% of women with moderate to severe pain associated with endometriosis reported having fatigue-related issues "quite a bit" or "very much," depending on the question asked. Fatigue extent was reduced to 29%-43% and 14%-29% for women treated with elagolix at 150 mg QD and 200 mg BID, respectively, at 6 months, compared with 35%-50% with placebo. The resultant decrease in fatigue T-scores was significant after elagolix treatment compared with placebo at 6 months, with changes of -2.21 and -5.90 with elagolix at 150 mg QD and 200 mg BID, respectively. Significant reduction in fatigue scores were observed among patients reporting clinically meaningful response "reduction" in dysmenorrhea, nonmenstrual pelvic pain, and dyspareunia (-7.31, -6.62, and -4.31, respectively) compared with nonresponders. CONCLUSION(S): In women with moderate to severe endometriosis related pain, elagolix significantly reduces fatigue levels.

Apoptotic cell-mimicking gold nanocages loaded with LXR agonist for attenuating the progression of murine systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) constitutes an autoimmune disease characterized by the breakdown of tolerance to self-antigens, sustained production of pathogenic autoantibodies, and damage to multiple organs and tissues. Nanoparticle (NP)-based therapeutics have demonstrated efficacy in attenuating the progression of SLE. However, investigations of nano-drugs that address the crucial initiating factor in the pathogenesis of SLE; e.g., inefficient clearance of apoptotic cells by phagocytes and consequent accumulation of self-antigens, have seldom been reported. Here, an apoptotic cell-mimicking gold nanocage (AuNC)-based nano drug carrier capable of correcting the impaired clearance of apoptotic cells in SLE was rationally designed and generated by conjugating phosphatidylserine (PS) on the surface of liposome-coated AuNCs for liver X receptor (LXR) agonist T0901317 delivery. Notably, PS-lipos-AuNC@T0901317 could efficiently enhance apoptotic cell clearance by elevating the expression of Mer, one of the pivotal phagocytosis-associated receptors on macrophages, resulting in decreased production of anti-dsDNA autoantibodies, reduced inflammatory response, and alleviation of kidney damage in lupus model mice. Additionally, PS-lipos-AuNC could be tracked by photoacoustic imaging for nano drug carrier biodistribution. By addressing the crucial pathogenic factor of SLE, the NP-based delivery system in this study is envisioned to provide a promising strategy to treat this complex and challenging disease.

Identification and Characterization of AES-135, a Hydroxamic Acid-Based HDAC Inhibitor That Prolongs Survival in an Orthotopic Mouse Model of Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive, incurable cancer with a 20% 1 year survival rate. While standard-of-care therapy can prolong life in a small fraction of cases, PDAC is inherently resistant to current treatments, and novel therapies are urgently required. Histone deacetylase (HDAC) inhibitors are effective in killing pancreatic cancer cells in in vitro PDAC studies, and although there are a few clinical studies investigating combination therapy including HDAC inhibitors, no HDAC drug or combination therapy with an HDAC drug has been approved for the treatment of PDAC. We developed an inhibitor of HDACs, AES-135, that exhibits nanomolar inhibitory activity against HDAC3, HDAC6, and HDAC11 in biochemical assays. In a three-dimensional coculture model, AES-135 kills low-passage patient-derived tumor spheroids selectively over surrounding cancer-associated fibroblasts and has excellent pharmacokinetic properties in vivo. In an orthotopic murine model of pancreatic cancer, AES-135 prolongs survival significantly, therefore representing a candidate for further preclinical testing.

Elagolix for endometriosis: all that glitters is not gold.

Elagolix, an orally active non-peptidic GnRH antagonist, has been approved by the Food and Drug Administration for the management of moderate to severe pain associated with endometriosis. As the degree of ovarian suppression obtained with elagolix is dose-dependent, pain relief may be achieved by modulating the level of hypo-oestrogenism while limiting side effects. Elagolix may thus be considered a novelty in terms of its endocrine and pharmacological properties but not for its impact on the pathogenic mechanisms of endometriosis, as the target of this new drug is, yet again, alteration of the hormonal milieu. Given the oestrogen-dependent nature of endometriosis, a reduction of side effects may imply a proportionate decrease in pain relief. Furthermore, if low elagolix doses are used, ovulation is not consistently inhibited, and patients should use non-hormonal contraceptive systems and perform serial urine pregnancy tests to rule out unplanned conception during periods of treatment-induced amenorrhoea. If high elagolix doses are used to control severe pain for long periods of time, add-back therapies should be added, similar to that prescribed when using GnRH agonists. To date, the efficacy of elagolix has only been demonstrated in placebo-controlled explanatory trials. Pragmatic trials comparing elagolix with low-dose hormonal contraceptives and progestogens should be planned to verify the magnitude of the incremental benefit, if any, of this GnRH antagonist over currently used standard treatments. The price of elagolix may impact on patient adherence and, hence, on clinical effectiveness. In the USA, the manufacturer AbbVie Inc. priced elagolix (OrilissaTM) at around $10 000 a year, i.e. $845 per month. When faced with unaffordable treatments, some patients may choose to forego care. If national healthcare systems are funded by the tax payer, the approval and the use of a new costly drug to treat a chronic condition, such as endometriosis, means that some finite financial resources will be diverted from other areas, or that similar patients will not receive the same level of care. Thus, defining the overall 'value' of a new drug for endometriosis also has ethical implications, and trade-offs between health outcomes and costs should be carefully weighed up.

Elagolix Alone or With Add-Back Therapy in Women With Heavy Menstrual Bleeding and Uterine Leiomyomas: A Randomized Controlled Trial.

OBJECTIVE: To evaluate elagolix, an oral gonadotropin-releasing hormone receptor antagonist, alone or with add-back therapy, in premenopausal women with heavy menstrual bleeding (greater than 80 mL per month) associated with uterine leiomyomas. METHODS: This double-blind, randomized, placebo-controlled, parallel-group study evaluated efficacy and safety of elagolix in cohorts 1 (300 mg twice daily) and 2 (600 mg daily) with four arms per cohort: placebo, elagolix alone, elagolix with 0.5 mg estradiol/0.1 norethindrone acetate, and elagolix with 1.0 mg estradiol/0.5 mg norethindrone acetate. A sample size of 65 per group was planned to compare elagolix with add-back to placebo on the primary end point: the percentage of women who had less than 80 mL menstrual blood loss and 50% or greater reduction in menstrual blood loss from baseline to the last 28 days of treatment. Safety assessments included changes in bone mineral density. RESULTS: From April 8, 2013, to December 8, 2015, 571 women were enrolled, 567 were randomized and treated (cohort 1=259; cohort 2=308), and 80% and 75% completed treatment, respectively. Participants had a mean±SD age of 43±5 years (cohort 2, 42±5 years), and 70% were black (cohort 2, 74%). Primary end point responder rates in cohort 1 (cohort 2) were 92% (90%) for elagolix alone, 85% (73%) for elagolix with 0.5 mg estradiol/0.1 mg norethindrone acetate, 79% (82%) for elagolix with 1.0 mg estradiol/0.5 mg norethindrone acetate, and 27% (32%) for placebo (all P<.001 vs placebo). Elagolix groups had significant decreases compared with placebo in lumbar spine bone mineral density, which was attenuated by adding 1.0 mg estradiol/0.5 mg norethindrone acetate. CONCLUSION: Elagolix with and without add-back significantly reduced menstrual blood loss in women with uterine leiomyomas. Add-back therapy reduced hypoestrogenic effects on bone mineral density. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01817530; EU Clinical Trial Register, 2013-000082-37.

Elagolix: First Global Approval.

Elagolix (ORILISSA™), an orally bioavailable, second-generation, non-peptide gonadotropin-releasing hormone (GnRH) receptor antagonist, is being developed AbbVie and Neurocrine Biosciences for the treatment of reproductive hormone-dependent disorders in women. In July 2018, the US FDA approved elagolix tablets for the management of moderate to severe pain associated with endometriosis. This approval was based on positive results in two replicate phase III trials; additional phase III trials in the USA, Canada and Puerto Rico are currently evaluating elagolix as both monotherapy and in combination with low-dose hormone add-back therapy in the same indication. Elagolix with and without low-dose hormone add-back therapy is also undergoing phase III clinical development for heavy menstrual bleeding associated with uterine fibroids in the aforementioned locations. This article summarizes the milestones in the development of elagolix leading to its first approval for the management of moderate to severe pain associated with endometriosis.