Myovant Sciences and Pfizer announce first participant dosed in phase III SERENE study of relugolix combination tablet for contraception.

Myovant Sciences and Pfizer Inc.announced that the first participant has been dosed in the Phase III SERENE study evaluating the contraceptive efficacy of relugolix combination tablet (relugolix 40 mg, estradiol 1.0 mg, and norethindrone acetate 0.5 mg) in healthy women ages 18-35 years who are at risk for pregnancy. The SERENE study will enroll 900 sexually active, healthy women ages 18-35 years with presumed normal fertility. The primary efficacy endpoint is the at-risk Pearl Index, defined as the number of on-treatment pregnancies per 100 women-years of treatment. On-treatment pregnancies are pregnancies with an estimated conception date between the first day of study intervention intake up to and including seven days after the last intake of study medication. Women will receive once-daily relugolix combination tablet for 13 28-day at-risk cycles. Safety data will also be collected during the study. Relugolix combination tablet is under review by the FDA for the treatment of women with uterine fibroids, with a decision expected by the June 1, 2021 target action date. The submission of a New Drug Application for the treatment of moderate to severe pain associated with endometriosis is anticipated in the first half of 2021.