AT AAGL 2107
NATIONAL HARBOR, MD. (FRONTLINE MEDICAL NEWS) – Elagolix, an oral gonadotropin-releasing hormone antagonist, improved dysmenorrhea and nonmenstrual pelvic pain for a year or more in women with surgically-diagnosed endometriosis in two extension studies.
Women who had participated in two pivotal, 6-month studies of elagolix were given the option to continue in an extension trial for another 6 months, Sukhbir S. Singh, MD, said at the AAGL Global Congress. He noted that “all my patients who completed the 6-month trial continued out to a year.”
Women who participated in Elaris EM-III (287 patients) and Elaris EM-VI (282 patients) were aged 18-49 years with surgically-diagnosed endometriosis and moderate to severe endometriosis pain. The average age in EM-III was 31 years while the average age in EM-IV was 33 years. About 90% of the women in both studies were white and the average body mass index hovered at the low end of overweight.
Patients continued on one of two doses of elagolix – 150 mg daily or 200 mg twice a day – with the lower dose providing partial estradiol suppression and the higher dose providing nearly complete suppression.
Patients tracked their dysmenorrhea and nonmenstrual pelvic pain scores on a 4-point scale daily using an electronic pain impact diary. They were classified as being responders if they experienced reduced dysmenorrhea and nonmenstrual pelvic pain equal to or better than they had during the original trial (much or very much improved on the Patient Global Impression of Change scale).
For each dose of elagolix, rates of response seen at 6 months in the original trial were maintained at a year or longer of continuous treatment, demonstrating long-term efficacy, Dr. Singh said. The average number of analgesic pills taken per month decreased from 46%-77% from baseline for all doses in the extension studies.
The most common adverse events were hot flushes, experienced by just over half (52%-55%) of women in the high-dose group and about 25%-30% of women in the lower-dose group. Severity was mild to moderate across the studies.
“The higher the dose you give, the more hot flushes you get,” said Dr. Singh , vice chair of gynecology at the University of Ottawa, Ontario. “But overall, patients often did not complain of this because they were getting pain relief as well.”
Other adverse events included headache in about 25%-30% of high-dose patients and 20% of low-dose patients, as well as nausea in about one-fifth of patients overall. Some decreases from baseline in bone mineral density were seen but there was progressive improvement upon discontinuation of elagolix, Dr. Singh noted.
Importantly, “these were patients who had endometriosis and pain, similar in makeup to groups studied by others. These studies did provide two dosing options to offer individualized approaches and pain results were controlled for use of rescue analgesia. But as extension trials, the studies are limited by having no placebo control and we did not know whether they had deep endometriosis or other pain issues,” Dr. Singh said.
Elagolix represents another treatment option for patients with endometriosis, Dr. Singh said. “One of the objections to taking currently approved [gonadotropin-releasing hormone] antagonists is that they are subcutaneous injections. Patients don’t like that – this is an oral option. It is quick to act and is rapidly reversible as well.”
Dr. Singh serves as a principal investigator and speaker for Allergan, AbbVie, and Bayer. The studies were sponsored by AbbVie.
On Twitter @denisefulton