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In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk. 2 FOCUSED ON UNMET NEEDS IN WOMEN’S HEALTH LINZAGOLIX OBE022 NOLASIBAN Potential to relieve symptoms Potential to delay preterm birth Potential to improve live birth from heavy menstrual bleeding to improve newborn health and rate following IVF & embryo due to uterine fibroids and pain reduce medical costs transfer associated with endometriosis 3 MULTIPLE PROGRAMS TO INNOVATE AND DRIVE VALUE PHASE 1 PHASE 2 PHASE 3 MARKET SIZE MILESTONES ~4M women diagnosed Positive 24W primary endpoint and treated in the U.S. results Q4:19, 52W results Uterine Fibroids – Ph3 PRIMROSE 2 EU & U.S. * expected Q2:20 24W primary endpoint data Uterine Fibroids – Ph3 PRIMROSE 1 U.S. expected LINZAGOLIX Q2:20 (OBE2109) MAA/NDA: Q4:20 / 1H::21 Oral GnRH ~5M women diagnosed Ph3 trials initiated Q2:19 Endometriosis – Ph3 EDELWEISS 2 U.S. receptor antagonist and treated in the U.S. Enrollment of new patients placed on voluntary hold Q1:20 amid Endometriosis – Ph3 EDELWEISS 3 EU & U.S. COVID-19 pandemic Positive Phase 2b results in Endometriosis – Ph2b EDELWEISS* 2018/19 Preterm Labor – Ph2a PROLONG 500,000 annual cases Phase 2a results expected OBE022 in both the U.S and 2H:20 Oral PGF2α Europe Pre-clinical/Phase 1 complete receptor antagonist Preterm Labor – Ph1 Resuming development IMPLANT 2 Ph3 met primary & secondary endpoints IVF – Ph3 IMPLANT 2/4 EU >2M IVF Global NOLASIBAN cycles/year IMPLANT 4 Ph3 missed primary endpoint Oral oxytocin receptor antagonist IVF – Ph 1/2 in China YuYuan BioScience (PRC): IND submission 2H:20 in China 4 * Primary and secondary endpoints met 2020 MAJOR CATALYSTS 5 COVID-19: Top priority is safety of patients, employees, healthcare professionals . Voluntary hold on enrollment of new patients in Phase 3 EDELWEISS trials . No impact on timing of PRIMROSE or PROLONG trial readout Phase 3 linzagolix trials in uterine fibroids . 12 month PRIMROSE 2 and 6 month primary endpoint PRIMROSE 1 readout in Q2:20 . MAA filing planned late 2020 Phase 2a OBE022 in preterm labor . PROLONG PART B readout in 2H:20 Linzagolix regional commercial partnership . 2020 corporate objective . Maximize best in class potential Nolasiban development in IVF proceeding in China . Partner YuYuan Bioscience submitting IND 2H:20 . Assessing higher and longer exposure to nolasiban 5 Linzagolix (OBE2109) DOSE- DEPENDENT ESTROGEN SUPPRESSION TO TREAT UTERINE FIBROIDS AND ENDOMETRIOSIS LINZAGOLIX M o A AND PK PROFILE Optimal PK profile to achieve clinical outcomes with once-daily dosing GnRH Hypothalamus Linzagolix Elagolix Relugolix Anterior pituitary 1. Linzagolix binds competitively to gland 75 mg 150 mg Endometriosis 40 mg with ABT** pituitary gland 200 mg with ABT* 200 mg BID GnRH receptors 2. Prevents receptor activation by endogenous GnRH Dose 100 mg Linzagolix Uterine Fibroids 300 mg BID with ABT 40 mg with ABT** FSH, LH Options 200 mg with ABT* 3. Rapid suppression of LH and FSH Dosing frequency / QD QD or BID QD day Estradiol Ovary Half-Life 14-15 hours 2-6 hours 37-42 hours 4. Gonadotropin suppression leads to dose-dependent decrease in serum estradiol Bioavailability > 80% 30 – 50% 11% concentration PK Elements Food Effect No No Yes Uterus CYP3A4 induction No Yes No (ABT, contraception) 7 Note: The data on this page are not from head-to-head comparisons. * ABT is not co-formulated with linzagolix to allow for use with or without according to physician choice; ** ABT is co-formulated with relugolix UTERINE FIBROIDS A LARGE MARKET WITH HIGH UNMET NEED Total U.S. costs estimated at up to 9million 70%+ women in the U.S. of women have $34B /yr suffer from fibroids fibroids by age 50 from direct costs, lost workdays and complications Quality 600,000 million Hysterectomies are performed > 4 of Life annually in the U.S. women in the U.S. are treated annually for fibroids Premenopausal women may experience heavy menstrual bleeding, anemia, bloating, 300,000 infertility, pain and swelling Are because of uterine fibroids 8 PRIMROSE 1 & 2 TRIALS PHASE 3 CLINICAL TRIALS FOR THE TREATMENT OF UTERINE FIBROIDS Primary Endpoint: Responder-HMB Reduction Main Study (N=500, 100/arm) Q4:19/Q2:20 Follow up Placebo + placebo add-back PRIMROSE 1 100% U.S. sites Placebo + placebo add-back 200mg + add-back 100 mg + placebo add-back 100 mg + placebo add-back Screening 100 mg + add-back 100 mg + add-back Follow-up 200 mg + placebo add-back 200 mg + add-back 200 mg + add-back 200 mg + add-back Placebo + placebo add-back 200 mg + add-back PRIMROSE 2 70% European sites 100 mg + placebo add-back 100mg + placebo add-back 30% U.S. sites 100 mg + add-back 100 mg + add-back Screening Follow-up 200 mg + placebo add-back 200 mg + add-back 200 mg + add-back 200 mg + add-back 8-14 Weeks 24 Weeks 28 Weeks 24 Weeks Aiming to support the registration of two regimens of administration 9 The trial was powered under the assumption of a 30% placebo response rate based on historical studies PRIMROSE 2 TRIAL PRIMARY ENDPOINT ACHIEVED FOR SIGNIFICANT AMENORRHEA* BOTH TARGET DOSING REGIMENS – RATE FOR BOTH TARGET DOSES RESPONDER* ANALYSIS P<0.001 P<0.001 p<0.001 p<0.001 100 100 93.9% 80 80 80.6% 60 60 56.7% 40 40 34.0% AMENORRHEA 20 29.4% 20 PROPORTION WOMENOF PROPORTION 11.8% 0 PROPORTION OF WOMEN WITH 0 Placebo Linzagolix Linzagolix Placebo Linzagolix Linzagolix 100mg 200mg + ABT 100mg 200mg + ABT * Primary endpoint is the proportion of women with * Amenorrhea is complete absence of bleeding during at menstrual blood loss ≤ 80 mL (by alkaline hematin least 35 consecutive days method) and ≥ 50% reduction from baseline 10 Error bars are 95% CI PRIMROSE 2 TRIAL KEY SECONDARY ENDPOINTS ACHIEVED Key Secondary Measurement p-value Endpoints Reduction in menstrual • Time to reduced menstrual blood loss (i.e., ≤80 mL and ≥50% reduction from p < 0.001 blood loss baseline) up to Week 24 • Number of days of uterine bleeding for the last 28-day interval prior p < 0.001 to Week 24 Amenorrhea • Percentage at Week 24 p < 0.001 • Time to amenorrhea up to Week 24 p < 0.001 Improvement in anemia • Hemoglobin level at week 24 in anemic subjects (defined as subjects with Hb < p < 0.001 12 g/dL at baseline) Reduction in pain • Change from baseline pain score at week 24 p < 0.001 Reduction in volume • Fibroid volume change from baseline at Week 24 o 100mg without ABT p < 0.055 o 200mg with ABT p < 0.008 • Uterine volume change from baseline at Week 24 p < 0.001 Improvement in • Change from baseline health-related quality of life (UFS-QoL*) at Week 24 p < 0.001 quality of life 11 * UFS-QoL = Uterine Fibroids Symptoms and Health-Related Quality of Life questionnaire EFFICACY DATA FROM RECENT TRIALS OF Gn RH ANTAGONISTS IN UTERINE FIBROIDS Caution advised when comparing across clinical trials.