Elagolix Seen to Lessen Pain and Spread of Endometriosis in Yearlong Phase 3 Studies

Elagolix Seen to Lessen Pain and Spread of Endometriosis in Yearlong Phase 3 Studies

Results of two Phase 3 extension studies showed that one year of treatment with elagolix could reduce pelvic pain, prevent proliferation of endometrium tissue, and improve quality of live in women with endometriosis.

Results of a Phase 2 clinical trial in women with uterine fibrosis also demonstrated the therapeutic potential of this investigative drug to reduce bleeding rates and improve quality of life of the patients.

These findings were presented during the American Society for Reproductive Medicine Scientific Congress & Expo (ASRM) recently held in San Antonio.

Elagolix, formerly known as ABT-620, is a gonadotropin-releasing hormone (GnRH) receptor antagonist that is being developed by AbbVie in collaboration with Neurocrine Biosciences.

Designed to be taken orally, it blocks the natural GnRH signals in the pituitary gland, inhibiting the production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and consequently leading to lower estradiol and progesterone production in the ovaries. These hormones — estradiol and progesterone  — are linked to the development and progression of endometriosis and uterine fibroids.

“An estimated one in 10 women of reproductive age have endometriosis,” Shao-Lee Lin, MD, vice president of therapeutic areas and international development at AbbVie, said, in a press release. “There have been few recent scientific advancements for women suffering from endometriosis and physicians are in need of additional treatment options to help manage this debilitating disease.”

Two pivotal and global clinical trials (NCT01620528 and NCT01931670), involving 1,700 women with endometriosis with moderate-to-severe menstrual and non-menstrual pain, found that elagolix at 200 mg given twice daily for up to six months could effectively reduce proliferation of endometrial tissue and pelvic pain complains.

Supported by these positive six-month results, the researchers extended the trials for up to 12 months of  treatment.

Analysis of the new data collected revealed that about 50 percent of the treated women reported reduced average monthly menstrual and non-menstrual pelvic pain scores upon one year of treatment. This effect was seen in both trials and was similar to what had been reported during the initial six months.

Long-term treatment did not reveal any new safety concerns. The incidence of hot flush was between 4 and 8 percent in the extension studies.

These data were presented ASRM in the study titled “Long-term safety and efficacy of elagolix treatment in women with endometriosis-associated pain: primary results from two phase 3 extension studies.”

Results of a second study, titled “Long-term effect of elagolix on the endometrium: results from two phase 3 extension studies in women with endometriosis-associated pain,” revealed that the inhibitory effects on tissue proliferation that had been reported during the initial six months of treatment were maintained over the additional six months.

In the presentation “Maintenance of endometriosis-associated pain reduction and quality of life improvement in phase 3 extension studies with elagolix,” the researchers showed that about 45% of patients who received 150 mg reported less pain during sexual intercourse, as did about 58% of those treated at the 200 mg dose. Analysis of overall quality of live scores also demonstrated a similar trend, showing positive changes when compared to baseline.

Evaluation of the potential effects of elagolix on bone mineral density revealed that about 0.8-0.9% of the patients who received 150 mg of elagolix experienced bone mineral density reduction of 8% or more by the end of a 12-month treatment period. A similar reduction was seen in 11–13% of patients  treated with 200 mg dose.

These results were presented in the study “Long-term effect of elagolix on bone mineral density: results from two phase 3 extension studies in women with endometriosis-associated pain.”

“Endometriosis is a chronic and painful disease,” said Eric Surrey, study investigator and medical director of the Colorado Center of Reproductive Medicine. “The results presented today are positive for patients and are consistent with previous data that demonstrate elagolix has the potential to be an important non-surgical treatment option for women suffering from the most prevalent symptoms of endometriosis.”

AbbVie has announced that it filled a request with the U.S. Food and Drug Administration (FDA) that elagolix be approved to treat endometriosis and associated pelvic pain. That application is under priority review with a decision expected by June 2018.

If approved, elagolix would become the first new oral therapeutic option for endometriosis-associated pelvic pain in more than a decade.

AbbVie is also exploring the impact of elagolix to treat women with uterine fibroids. At the ASRM meeting, the company presented the latest data from a Phase 2 clinical trial (NCT01817530) that evaluated the safety and efficacy of elagolix, alone or combination with add-back therapy, for the treatment of heavy menstrual bleeding in premenopausal women with uterine fibroids.

Researchers reported that the majority of patients treated with elagolix alone showed significant change in menstrual blood loss compared to placebo, as well as a decrease in tissue proliferation. Similar to what was reported in previous studies, elagolix alone was associated with hot flushes and a reduction in bone mineral density. Addition of add-back therapy lessened these adverse effects in a dose-dependent manner.

The researchers also presented the results of elagolix impact on the patients’ quality of live. Women treated with the investigative therapy, both alone and in combination, were said to experience clinically meaningful improvements in symptom severity and health-related quality of life scores, including sexual function, compared to placebo.

AbbVie also presented data at ASRM on healthcare utilization and costs associated with endometriosis in the United States, detailed in the study “Direct healthcare utilization and costs associated with endometriosis among women with medicaid insurance.”

This study included 15,615 women with endometriosis who were diagnosed between January 2008 and September 2014, and were registered in the Medicaid database. A total of 86,829 women without endometriosis were included as controls.

Analysis of data collected during the year following inclusion in the database showed that endometriosis patients had significantly higher insurance utilization rates, associated with higher costs. About 66% of patient underwent at least one endometriosis-related surgery.

Pharmacy costs accounted for 15.3% of total healthcare costs, and endometriosis-related expenses accounted for about 22.4% of total costs among endometriosis patients.