Elagolix, an oral GnRH antagonist, versus subcutaneous depot medroxyprogesterone acetate for the treatment of endometriosis: effects on bone mineral density

Abstract

This randomized double-blind study, with 24-week treatment and 24-week posttreatment periods, evaluated the effects of elagolix (150 mg every day, 75 mg twice a day) versus subcutaneous depot medroxyprogesterone acetate (DMPA-SC) on bone mineral density (BMD), in women with endometriosis-associated pain (n = 252). All treatments induced minimal mean changes from baseline in BMD at week 24 (elagolix 150 mg: -0.11%/-0.47%, elagolix 75 mg: -1.29%/-1.2%, and DMPA-SC: 0.99%/-1.29% in the spine and total hip, respectively), with similar or less changes at week 48 (posttreatment). Elagolix was associated with improvements in endometriosis-associated pain, assessed with composite pelvic signs and symptoms score (CPSSS) and visual analogue scale, including statistical noninferiority to DMPA-SC in dysmenorrhea and nonmenstrual pelvic pain components of the CPSSS. The most common adverse events (AEs) in elagolix groups were headache, nausea, and nasopharyngitis, whereas the most common AEs in the DMPA-SC group were headache, nausea, upper respiratory tract infection, and mood swings. This study showed that similar to DMPA-SC, elagolix treatment had minimal impact on BMD over a 24-week period and demonstrated similar efficacy on endometriosis-associated pain.

Keywords: GnRH antagonists; elagolix; endometriosis; pelvic pain.

Conflict of interest statement

Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: BC has been a consultant for AbbVie Inc. WPD has been a consultant for Neurocrine Biosciences, Inc and AbbVie Inc. JB, RJ, and CO are Neurocrine Biosciences, Inc employees and own Neurocrine Biosciences, Inc stock. KC and PJ are AbbVie Inc employees and own AbbVie Inc stock; EG is a former AbbVie Inc employee.

© The Author(s) 2014.

Figures

Figure 1.

Bone mineral density least square (LS) mean change from baseline ± 95% confidence interval at weeks 24 and 48.

Figure 2.

Median estradiol concentrations through week 48.

Figure 3.

Composite pelvic signs and symptoms score (CPSSS) mean ± standard error of the mean (SEM) component scores for (A) dysmenorrhea, (B) nonmenstrual pelvic pain, and (C) dyspareunia.

Figure 3.

Composite pelvic signs and symptoms score (CPSSS) mean ± standard error of the mean (SEM) component scores for (A) dysmenorrhea, (B) nonmenstrual pelvic pain, and (C) dyspareunia.