June 2020 DISCLAIMER

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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

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 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 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 Ovary Half-Life 14-15 hours 2-6 hours 37-42 hours

4. 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. Below data are not head-to-head comparison, and no head-to-head trials have been completed, nor are underway

Linzagolix Relugolix Elagolix PRIMROSE 2 LIBERTY 1 LIBERTY 2 ELARIS 1 ELARIS 2 Mean Age (y) 43.1 41.3 42.1 42.6 42.5 Baseline Menstrual Blood Loss 212 229 227 238 229 (mL per cycle) Dose 200mg + ABT 40mg + ABT 300mg + ABT Regimen Once daily Once daily Twice daily Responder² Rate (RR) (%) 93.9 73.4 71.3 68.5 76.5 Placebo-adjusted RR (%) 64.5 54.8 56.5 60.0 66.0 Amenorrhea (%) 80.6 52.3 50.4 48.1 52.9 Placebo-adjusted RR (%) 68.8 46.8 - 43.7 48.2 Pain    NR NR Fibroid Volume    NR NR Uterine Volume    NR NR Menstrual Blood Loss      Anemia      Quality of Life     

12 Source: Company information – Note: NR = not reported. ² PRIMARY ENDPOINT: Proportion of women with menstrual blood loss ≤ 80 mL (by alkaline hematin method) and ≥ 50% reduction from baseline PRIMROSE 2 TRIAL SUMMARY OF ADVERSE EVENTS

Placebo Linzagolix Linzagolix Linzagolix Linzagolix Total Treatment emergent 100 mg 100 mg 200 mg 200 mg adverse events, n (%) + ABT + ABT

n=105 n=99 n=102 n=104 n=101 n=511

Subjects with at least 47 (44.8) 50 (50.5) 45 (44.1) 62 (59.6) 51 (50.5) 255 (49.9) one TEAE

Vascular disorders* 6 (5.7) 15 (15.2) 12 (11.8) 36 (34.6) 14 (13.9) 83 (16.2)

* Vascular disorders include hot flushes, hypertension, flushing, varicose veins

. Most common TEAEs (>5%)

‒ Hot flushes (13.9%) ‒ Anemia (10.4%) ‒ Headache (6.8%)

13 PRIMROSE 2 TRIAL BMD % CHANGE FROM BASELINE AT WEEK 24

Mean % change in BMD from baseline to 24 weeks

Lumbar Spine Total hip Femoral neck 2 100mg 200mg + ABT 1 Placebo

0 100mg

-1 100mg + ABT

200mg -2 200mg + ABT -3

-4

-5

Error bars are 95% CIs Patients in the trial received no vitamin D or calcium supplementation

14 * ABT: Add Back Therapy (estradiol + norethindrone acetate) PRIMROSE 2 – DEMOGRAPHICS & BMD IMPACT NO DIFFERENCE IN BMD EXPECTED BETWEEN Gn RH ANTAGONISTS

PRIMROSE 2 – PRIMROSE 1 ELARIS-I ELARIS-2 LIBERTY 1 LIBERTY 2 OVERALL US only* (EGX) (EGX) (RGX) (RGX) POPULATION*

Subjects (n) 501 526 308 283 255 254

Black (%) 5.2% 64.3% 68/66% 67/66% 42/41% 42/42%

Age (mean year/SD) 42.9 (5.3) 41.6 (5.9) 41/42 42/42 42/41 42/42

Weight (kg/SD) 74.06 (15.90) 91.48 (19.78)

BMI (mean /SD) 27.02 (5.57) 32.70 (6.84) 34/33 34/33 32/31 32/31 24 Week BMD Change (%, spine) -1.31% - -0.76% -0.61% -0.36% -0.13%

• Blacks have higher BMD and are more resistant to BMD loss than Caucasians • Higher body weight and BMI are protective against BMD loss • Vitamin D/Calcium supplementation reduces BMD loss at 12 months by an estimated 0.5%*

* PRIMROSE Trials no Vitamin D/Calcium supplementation 15 Source: Company information. MARKET FEEDBACK WHAT MATTERS FOR UTERINE FIBROIDS PATIENTS?

Method Discreet choice modeling based on the responses of 101 U.S. patients with symptomatic uterine fibroids

Rank ordered perceived incremental value of the tested component levels in UF patients choice

Pain Bleeding Need Hot Daily Amenorrhea Reduction Reduction for ABT Flushes Intake

In 8 /10 pts The ‘full package’ is In 8 /10 1 pts No need required to win In 6 /10 pts In 8 /10 pts In 1 /10 Gain in pts QD utility In 6 /10 values pts In 6 /10 2 ABT matters for women from the pts least to the In 3 /10 most pts positive perceived levels 0.0 In 4 /10 0.0 In 4 /10 0.0 Required 0.0 In 4 /10 0.0 In 5 /10 0.0 BID Nearly 1/3 of women suffering pts pts pts pts from HMB due to uterine fibroids Utility values are calculated for each attribute level to express their perceived relative value for patients would prefer to avoid ABT when choosing the UF treatment they would prefer to receive instead of the current/latest one 16 Source: AplusA US patient research (n = 101), Oct-Dec 2019 MARKET RESEARCH WHAT MATTERS FOR CLINICIANS?

Method Discrete choice modeling based on the responses of 131 US gynecologists

Perceived incremental value of the tested components levels in UF treatment choice

Yearly Bleeding Pain Hot Need Daily Cost Reduction Reduction Flushes for ABT Intake

$5 000 1 Price is key driver In 8 /10 $6 250 pts

$7 500 In 8 /10 Gain in In 6 /10 2 Bleeding outranks pain pts utility pts values $8 750 from the In 1 /10 worst to In 6 /10 pts best pts In 3 /10 No need QD perceived pts levels In 4 /10 3 ABT less influential 0.0 $10 000 0.0 0.0 In 4 /10 0.0 In 5 /10 0.0 Required 0.0 BID pts pts pts

Incremental utility values for each attribute are calculated for each attribute level to express the perceived incremental value for physicians when going from one level to the next one for this attribute when choosing a GnRH analogue 17 Source: AplusA US clinician research (n = 131), Oct-Dec 2019 LINZAGOLIX DELIVERING THE FULL POWER OF THE Gn RH ANTAGONIST CLASS

The only GnRH antagonist offering two dosing options to treat MORE women for both uterine fibroids and endometriosis

1 Linzagolix 200 mg with ABT, first choice for its outstanding efficacy

Linzagolix 100 mg without ABT, first choice when ABT is a potential 2 safety, tolerability or preference issue*

Study results & market surveys confirm potential best-in-class

18 * Thromboembolic history or risk, CV history or risk , breast cancer history or risk, intolerance to ABT, patient preference, ENDOMETRIOSIS AN EMOTIONALLY AND PHYSICALLY PAINFUL CONDITION

Total U.S. costs estimated at up to 176 million 60% /yr women worldwide suffer of women will feel symptoms $22B from endometriosis by age 16

Endometriosis affects up to

Quality in the general 5 million 10% population of Life women in the U.S. are treated annually in the infertile for endometriosis Premenopausal women may population experience pelvic pain, pain 50% during intercourse and defecation, infertility and emotional distress in patients with 60% chronic pelvic pain 19 PHASE 2B EDELWEISS TRIAL Enrollment 328 patients, ~65/arm 50 sites in U.S. (n=177) ENDOMETRIOSIS PATIENTS 14 sites in EU (n= 151)

MAIN STUDY FOLLOW UP

PRIMARY ENDPOINT: SECONDARY ENDPOINT: VRS PAIN SCORE RESPONDER RATE BMD**

PLACEBO 50mg daily 50mg daily FOLLOW-UP 75mg daily 75mg daily LEAD-IN 100mg daily 100mg daily

200mg daily 200mg daily OPTIONAL EXTENSION: 75mg daily* *Titrated dose 50-100mg 6M + 6M FOLLOW-UP

8–14 WEEKS 12 WEEKS 12 WEEKS 24 WEEKS

20 * Titration after 12 weeks based on E2 serum level at weeks 4 and 8 **BMD: Bone Mineral Density PHASE 2B EDELWEISS TRIAL KEY DOSES MET EFFICACY ENDPOINTS

Dysmenorrhea (%) Overall Pelvic Pain (%) Responder (0-3 VRS)

Responder (0-3 VRS) Plc 75mg 200mg

Plc 75mg 200mg 78,9 84,1 77,3 68,2 58,3 70,8 *** 61,5 *** 56,3 28,5 ** 0 * 34,5 Week 12 Week 24

Non-menstrual Pelvic Pain (%) Responder (0-3 VRS) Week 12 Week 24 Plc 75mg 200mg 72,9 72,7 58,5 47,7 37,1 * . Potential point of differentiation as 75mg partial suppression dose is nearly as effective as 200mg full suppression dose Week 12 Week 24

21 * p value <0.05 ** p value <0.01 *** p value <0.001 for linzagolix doses compared to placebo PHASE 2B EDELWEISS TRIAL – DOSE FINDING, NO ABT 75mg EFFECTIVE WITHOUT SIGNIFICANTLY AFFECTING BMD

Mean % change in BMD from baseline to 24 weeks (12 weeks for placebo)

Lumbar Spine Total hip Femoral neck 2 75mg 200mg

1 Placebo

50mg 0 75mg FD -1 100mg

-2 200mg

-3

-4 Error bars are 95% CIs

22 * ABT: Add Back Therapy (estradiol + norethindrone acetate) PHASE 3 ENDOMETRIOSIS ONGOING TRIALS EDELWEISS 2 AND 3

MAIN STUDY FOLLOW UP

CO-PRIMARY ENDPOINT: DYS/ NMPP RESPONDER ANALYSIS

INITIATED 1H:19 75mg daily

PLACEBO 200mg daily + ABT FOLLOW-UP LEAD-IN 75mg daily 75mg daily

200mg daily + ABT 200mg daily + ABT

6 MONTHS TREATMENT 6 MONTHS EXTENSION STUDY 11±5 WEEKS 6 MONTHS

23 LINZAGOLIX 24 A SIGNIFICANT OPPORTUNITY

LINZAGOLIX is the ONLY GnRH antagonist currently developed as two different, SIMPLE & WELL TOLERATED regimens of administration for both indications

1 Large markets with significant unmet need in U.S. . ~ 4M treated for heavy menstrual bleeding resulting from uterine fibroids . ~ 5M treated for endometriosis associated pain

2 Potentially best-in-class GnRH antagonist . Best-in-class response for HMB control in uterine fibroids and pain control in endometriosis with full suppression option Differentiated regimen . Only GnRH under development for women who cannot or do not want to take ABT in both indications offering compelling . Convenient, oral, once-daily dosing commercial proposition

3 Commercial launches in 2022 . Commercialization through partnership under assessment 24 . Strong IP: exclusivity beyond 2036 OBE022

POTENTIAL TO DELAY PRETERM BIRTH TO IMPROVE NEWBORN HEALTH AND REDUCE MEDICAL COSTS 26 PRETERM DELIVERY: LIFE ALTERING & COSTLY BABIES SURVIVING PREMATURE BIRTH FACE GREATER RISK OF NEONATAL COMPLICATIONS AND LIFELONG DISABILITIES

Preterm birth is the more than LEADING CAUSE 1 in 10 1 million of death of children under 5 babies are born premature Prematurity related deaths in 2015 years of age

TREMENDOUS MEDICAL & SOCIETAL COST

$50K $195K $26B+ $16.9B+ Average cost for a Average cost per survivor U.S. economic U.S. Infant medical preterm infant (U.S.) infant born 24-26 weeks burden care costs

26 MODE OF ACTION OF PGF2α RECEPTOR ANTAGONIST TO CONTROL PRETERM LABOR

Phospholipids

Arachidonic Acid

PGHS -1/2 = COX1/2 Selectively Has the potential to PGH2 blocks the treat preterm labor OBE022 PGF2α with improved receptor safety over NSAIDs PGE2 PGF2α x EP1 EP2 FP EP3 EP4

UTERUS: contract relax contract

27 OBE022 PROLONG PH2A STUDY PART B

Dosing: 7 days up Study design: to 60 patients Double-blind, randomized Atosiban + OBE022 Followed thru delivery Main Study versus Atosiban + Placebo completion ~120 patients Interim Interim Update 30 Update 60 Endpoint: patients patients Complete 7 days of dosing without delivery

Final Part B: Main analysis 24-month Infant FU

Q1:18 2H:20 2H:22 IDMC Reviews

28 FINANCIAL OUTLOOK 2020/21 Achievements Key Milestones March 31, 2020 CASH: . Completion of PRIMROSE 1 and 2 $62 million . regulatory filings (EU & US) . PROLONG readout EXPECTED CASH RUNWAY: . Nolasiban phase 1 trial results in China Q3:21 including credit facility Ongoing Activities . EDELWEISS 2 and 3 continuation FIRST LINZAGOLIX COMMERCIAL LAUNCH: . Nolasiban phase 2 initiation in China . Preparing commercialization of linzagolix EU Q1:22 through partnership(s)

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