CENTAUR Study: cenicriviroc in NASH (phase 2b) Design Randomisation * 2:1:1 Double-blind Year 1 Year 2 Adults NASH (liver biopsy) + NAS ** ≥ 4 (≥ 1 in each component) + Liver fibrosis (NASH CRN stages 1 to 3) + ≥ 1 of the following: diabetes mellitus, BMI > 25 kg/m2 + ≥ 1 component of metabolic syndrome, bridging fibrosis (NASH CRN stage 3), NAS ≥ 5 CVC 150 mg N = 289 Placebo CVC 150 mg Placebo Placebo ** NAS (NAFLD Activity Score): steatosis (0 to 3), lobular inflammation (0 to 3), ballooning (0 to 2) * Randomisation was stratified by NAS (4 or ≥ 5) and fibrosis stage (≤ 2 or > 2) Cenicriviroc: oral dual antagonist of CCR-2 and CCR-5 Objective Primary: hepatic histologic improvement at year 1 (≥ 2 point in NAS with ≥ 1 point in lobular inflammation or ballooning) with no worsening of fibrosis ; superiority of CVC vs placebo, 80% power Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67, Ratziu, EASL 2018, Abs. GS-002

CENTAUR Study: cenicriviroc in NASH (phase 2b) Baseline characteristics and disposition CVC, N = 145 Placebo, N = 144 Mean age, years 55 54 Female 50% 55% Mean BMI, kg/m2 33.6 34.1 Diabetes mellitus 57% 44% ≥ 3 criteria of metabolic syndrome, % 72 Liver histology NASH CRN fibrosis stage 1 / 2 / 3 NAS Mean ≥ 5, % Mean steatosis Mean lobular inflammation Mean ballooning 32% / 29% / 39% 5.3 73.1% 1.4 2.4 1.5 33% / 28% / 38% 5.4 75.0% Discontinued before end of Year 1, N For adverse event Withdrew consent 20 9 10 18 8 7 Entered Year 2 of the study, N Early withdrawal, N / for adverse event, N 121 12 / 5 CVC = 61 2 /1 PCB = 60 2 /0 Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67, Ratziu, EASL 2018, Abs. GS-002

CENTAUR Study: cenicriviroc in NASH (phase 2b) Primary endpoint at Year 1: improvement in NAS and no worsening of fibrosis, ITTm 10 20 30 40 50 15.9 18.8 OR = 0.82 (0.44 - 1.52) p = 0.52 CVC N = 145 Placebo N = 144 % Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67

CENTAUR Study: cenicriviroc in NASH (phase 2b) Key secondary endpoint at Year 1: improvement in fibrosis by ≥ 1 stage and no worsening of steato-hepatitis by baseline characteristics All patients By NAS 10 20 30 21.6 18.8 p = 0.77 OR = 1.2 (0.37 ; 3.9) 23.6 9.6 p = 0.013 OR = 2.92 (1.26 ; 6.78) 37 32 89 94 NAS = 4 NAS > 5 N = % 10 20 30 10.4 OR = 2.20 (1.11 ; 4.35) p = 0.023 % CVC Placebo By Fibrosis stage (NASH CRN) By ballooning grade 13.6 4.8 p = 0.175 OR = 3.16 (0.6 ; 16.62) 22.9 8.8 p = 0.123 OR = 3.06 (0.74 ; 12.71) 31.9 20 p = 0.183 OR = 1.88 (0.74 ; 4.73) 28 15.5 p = 0.049 OR = 2.2 (1.0 ; 4.7) 44 Stage 1 10 30 40 N = 42 35 34 47 50 82 84 Stage 2 Stage 3 Pooled stage 2 and 3 % 17.7 15.8 p = 0.78 OR = 1.15 (0.44 ; 3.02) 28.1 8.7 p = 0.0056 OR = 4.1 (1.51 ; 11.2) 62 57 64 69 Grade 1 Grade 2 10 20 30 40 N = % Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67

CENTAUR Study: cenicriviroc in NASH (phase 2b) Improvement in fibrosis by ≥ 1 stage and no worsening of steato-hepatitis 15/126 (12%) 6/32 (19%) 9/94 (10%) 2/42 (5%) 3/34 (9%) 10/50 (20%) 9/57 (16%) 6/69 (9%) 7/61 (12%) 10/81 (12%) 4/41 (10%) 5/45 (11%) 4/28 (14%) 3/19 (16%) 5/69 (7%) 10/57 (18%) 29/126 (23%) 8/37 (22%) 21/89 (24%) 6/44 (14%) 8/35 (23%) 15/47 (32%) 11/62 (18%) 18/64 (28%) 17/66 (26%) 11/54 (20%) 8/31 (26%) 7/32 (22%) 8/51 (16%) 6/22 (27%) 7/19 (37%) 15/52 (23%) 17/74 (23%) Overall mITT population NAS = 4 NAS > 5 Stage 1 Stage 2 Stage 3 Grade 1 (few ballon cells) Grade 2 (prominent ballooning) Grade 2 (2-4 foci/200x) Grade 3 (> 4 foci/200x) Grade 1 (5-33 %) Grade 2 (> 33-66 %) < 30 kg/m² > 30 - < 35 kg/m² > 35 - < 40 kg/m² > 40 kg/m² Not present Present NAS Fibrosis stage (NASH CRN) Hepatocellular ballooning Lobular inflammation Steatosis BMI Type 2 diabetes status Favors placebo Favors CVC Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67

CENTAUR Study: cenicriviroc in NASH (phase 2b) Change in liver biopsy at year 1 (IPP population) CVC N = 123 Placebo Improved No change Worsened Steatosis 19.5 74.0 6.5 25.2 61.8 13.0 Lobular inflammation 31.7 43.9 24.4 27.6 49.6 22.8 Ballooning 26.8 54.5 18.7 35.0 50.4 14.6 Biomarkers of inflammation Marked reductions in circulating biomarkers of systemic inflammation (high-sensitivity C-reactive protein, interleukin-6, interleukin-8, fibrinogen, and IL-1ß) and of monocyte activation (sCD14) were observed with CVC (vs placebo). Persistence of systmeic anti-inflamamtory activity at Year 2, without no metabolic disturbances Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67, Ratziu, EASL 2018, Abs. GS-002

CENTAUR Study: cenicriviroc in NASH (phase 2b) Main outcomes at Year 2 Improvement in fibrosis (≥ 1 stage) Improvement in fibrosis (≥ 1 or ≥ 2 stages) and no worsening of NASH Maintenance of antifibrotic response from Year 1 to Year 2 (groups with 2 years CVC vs 2 years of placebo) Effects of 2 years of CVC treatment (groups with 2 years CVC vs 2 years of placebo) Effects of 1 year of CVC treatment (immediate or deferred CVC vs placebo) Safety and tolerability of CVC vs placebo during Year 2 Cenicriviroc - Phase 2b Ratziu, EASL 2018, Abs. GS-002

CENTAUR Study: cenicriviroc in NASH (phase 2b) Antifibrotic response at year 2, ITTm CVC Placebo 10 20 30 40 N evaluable = N enrolled = 26 22 p = 0.63 15 17 p = 0.94 11 3 p = 0.13 99 145 54 72 65 86 34 50 Stage 2 or 3 % Improvement in fibrosis by ≥ 1 stage and no worsening of NASH fibrosis by ≥ 2 stages Cenicriviroc - Phase 2b Ratziu, EASL 2018, Abs. GS-002

CENTAUR Study: cenicriviroc in NASH (phase 2b) Adverse events and laboratory abnormalities, % CVC 1st year N = 144 Placebo 1st year N = 145 CVC 2nd year N = 182 Grade 3-4 drug-related adverse event 8.3 6.3 12.1 Serious adverse event 11.1 6.9 NA Discontinuation for adverse event 2.7 Most common adverse events of grade ≥ 2 Fatigue Diarrhea Headache ALT increase ≥ grade 2 2.8 2.1 1.4 0.7 3.5 7.1 Grade 3-4 laboratory abnormalities Fasting serum glucose > 250 mg/dL ALT > 5 x ULN AST > 5 x ULN Triglycerides grade 3 / grade 4 Gamma-GT grade 3 / grade 4 Creatine kinase grade 3 / grade 4 Uric acid grade 3 / grade 4 Amylase > 2-5 x ULN Phosphorus < 2-1 mg/dL Absolute neutrophil grade 3 / grade 4 11.9 11.8 4.9 3.5 / 2.1 5.6 / 0.7 4.2 / 1.4 6.3 / 7.6 4.2 1.4 / 1.4 9.2 4.9 / 2.1 4.2 / 0.7 4.9 / 1.4 6.3 / 4.2 0.7 2.1 / 0.7 Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67, Ratziu, EASL 2018, Abs. GS-002

CENTAUR Study: cenicriviroc in NASH (phase 2b) Summary CVC showed a significant antifibrotic benefit at year 1 and was well tolerated Although the primary endpoint of the study was not met, the fact that the CENTAUR year 1 study results showed that CVC provided clinically meaningful benefits and resulted in twice as many subjects achieving improvement in fibrosis by 1 stage and no worsening of steato-hepatitis as compared to placebo suggests that the study did, in fact, show proof of concept, warranting phase 3 development of CVC Year 2 analyses corroborate CVC antifibrotic activity in adults with NADH and liver fibrosis Effect more pronounced in stage 3 fibrosis Cenicriviroc - Phase 2b Friedman SL, Hepatology 2018;67:1754-67, Ratziu, EASL 2018, Abs. GS-002