An Extension Study to Evaluate the Efficacy and Safety of Elagolix in Premenopausal Women With Heavy Menstrual Bleeding Associated With Uterine Fibroids

Inclusion Criteria:

- Participant has completed the 6-Month Treatment Period of their respective Pivotal
Study (either Study M12-815 or Study M12-817).

- Participant did not meet removal criteria in bone mineral density (BMD) decrease in
the spine, total hip and femoral neck at Month 6 of the Treatment Period of their
respective Pivotal Study

- Participant has negative urine and/or serum pregnancy test(s) results were
consistently negative during the Treatment Period of their respective Pivotal Study
and prior to first dose in this study.

- Participant's endometrial biopsy from the Month 6 Visit of their respective Pivotal
Study shows no clinically significant endometrial pathology.

Exclusion Criteria:

- Participant met criteria for removal from therapy in her respective Pivotal Study.

- Participant is planning a pregnancy within the next 18 months.

- Participant has current suicidal markers as noted at the Month 6 visit of her
respective pivotal study.

- Participant has any new medical conditions that may be unsuitable for participation.

- Participant is using any systemic corticosteroids for over 14 days or is likely to
require treatment with systemic corticosteroids during the course of the study.
Over-the-counter and prescription topical, inhaled, intranasal or injectable (for
occasional use) corticosteroids are allowed.