Last updated on August 2019

SPIRIT 1: Efficacy and Safety Study of Relugolix in Women With Endometriosis-Associated Pain

Brief description of study

The purpose of this study is to determine the benefit and safety of relugolix 40 mg once daily, co-administered with low-dose estradiol and norethindrone acetate compared with placebo for 24 weeks, on dysmenorrhea and on nonmenstrual pelvic pain.

Detailed Study Description

This study is an international phase 3 randomized, double-blind, placebo-controlled efficacy and safety study to evaluate 24 weeks of oral, once-daily relugolix (40 mg) co-administered with either 12 or 24 weeks of low-dose estradiol (1.0 mg) and norethindrone acetate (0.5 mg), compared with placebo.

Approximately 600 women with endometriosis-associated pain will be enrolled and randomized 1:1:1 to Group A - relugolix plus low-dose hormonal add-back therapy, Group B - relugolix monotherapy for 12 weeks followed by co-administration with low-dose hormonal add-back therapy, or Group C - placebo (N = 200 per group).

Once eligibility has been confirmed, patients will be randomized on Baseline Day 1 to Treatment Group A, B or C, and will begin double-blinded study drug treatment on Day 1. Between the Baseline Day 1 and Week 24 visits, patients will attend visits every 4 weeks, and will take the blinded study treatment (1 tablet and 1 capsule) orally once daily for 24 weeks. The last dose of study drug will be taken on the day prior to the Week 24 visit.

Eligible patients, including women randomized to placebo, will be offered the opportunity to enroll in a 28-week open label extension study where patients will receive relugolix co-administered with low-dose estradiol and norethindrone acetate. Patients who do not enroll into the extension study will have a Follow-Up visit approximately 30 days after the patient's last dose of study drug.

Clinical Study Identifier: NCT03204318

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