Elagolix in endometriosis-related pain: a profile of its use as approved in the USA

Elagolix (Orilissa™), an oral non-peptide gonadotropin-releasing hormone receptor antagonist, is approved for the management of moderate to severe pain associated with endometriosis in the USA and Canada. It reduces levels of gonadotropins, thereby suppressing ovarian sex hormones, ovulation, and endometrial proliferation. In phase 3 trials in women with moderate to severe endometriosis-related pain, elagolix 150 mg once daily and 200 mg twice daily improved clinical response rates for dysmenorrhea and non-menstrual pelvic pain to a significantly greater extent than placebo at 3 and 6 months of treatment. Improvements from baseline in several other endometriosis pain-related outcomes were also better with elagolix than with placebo, with the benefits of treatment being maintained with treatment for an additional 6 months in extension studies. Elagolix is generally well tolerated, with most adverse events being of mild to moderate severity. However, elagolix is associated with a dosage-dependent risk of bone loss, which limits its duration of therapy, use in at-risk patients, and concomitant use with certain drugs.