ObsEva SA announced several important updates on its Yselty program. The Marketing Authorization Application (MAA) is an application for approval submitted to the European Medicines Agency (EMA) and is a critical step in marketing a product in the EU. Validation marks the beginning of the review period. The Yselty MAA for the uterine fibroids’ indication is based on data from the Phase 3 PRIMROSE 1 study (conducted in the US, which enrolled 574 women with uterine fibroids) and PRIMROSE 2 (conducted in Europe and the US, which enrolled 535 women with uterine fibroids). In both studies, patients with heavy menstrual bleeding (HMB) associated with uterine fibroids were administered Yselty doses of 100 mg or 200 mg, with and without hormonal add-back-therapy (ABT; 1 mg estradiol/0.5 mg norethisterone acetate), or placebo. PRIMROSE 1 and 2 successfully met their primary endpoint, with all doses showing statistically significant and clinically relevant reductions in HMB compared to placebo. There was a clear efficacy dose response, with the highest responder rates for the primary endpoint observed in women who received the 200 mg with ABT dose. Highly significant efficacy was also achieved for the low-dose 100 mg non-ABT regimen. Substantial improvements were also observed with all doses for the secondary endpoints of amenorrhea, time to reduced menstrual blood loss, hemoglobin levels in anemic subjects, pain, and quality of life. ObsEva anticipates follow-up data and 6-month post treatment assessment data in first quarter 2021. The clinical development program for the endometriosis indication is a key priority for ObsEva. The EDELWEISS 3 trial in the EU is progressing as planned, with primary endpoint data expected in fourth quarter 2021. Screening and enrollment for EDELWEISS 2 in the US has been increasingly challenging, particularly in the context of the persisting difficult environment of the ongoing pandemic and has led to ObsEva’s decision to discontinue the study. No new or significant safety issues have been observed. The ongoing Phase 3 EDELWEISS 3 study will enroll approximately 450 patients with endometriosis associated pain, with a co-primary endpoint of response on both dysmenorrhea (menstrual pain) and non-menstrual pelvic pain. The study includes a 75 mg once daily dose without hormonal ABT, and a 200 mg once daily dose in combination with hormonal ABT (1mg E2 /0.5mg NETA). Subjects who have completed the initial six-month treatment period will have the option to enter a 6-month treatment extension. Data from the primary endpoint readout are expected in fourth quarter 2021. Yselty® (linzagolix, previously known as OBE2109) is a novel, oral, once daily, GnRH receptor antagonist with a potentially best-in-class profile. Yselty is currently in late-stage clinical development for the treatment of heavy menstrual bleeding associated with uterine fibroids and pain associated with endometriosis. ObsEva licensed Yselty from Kissei in late 2015 and retains worldwide commercial rights, excluding Asia, for the product. Yselty® is a registered trademark owned by Kissei for use by ObsEva. Yselty® is not yet approved for use anywhere in the world.