MANAGEMENT PRESENTATION

JUNE, 2019 Presentation Disclaimer

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2 To Become Globally Recognized as the Leading Chinese Biopharma

3+ Years Since Company Inception

World-class $150M $262M $328M Management Team Series A Series B HK IPO (July 2016) (May 2018) (Feb 2019)

15 Assets, All Oncology Integrated 4 Potentially First-in-Class Assets Biopharma with Clear Focus on Clinical 3 Clinical-stage IO Backbones to Drive Combo Potential Development 5 Late-stage Assets, 1 NDA submission 13 Clinical Trials, 20 IND / CTA submissions1

Note: 118 approved, 1 withdrawn, 1 under review 3 Industry Leading Management Team with Proven Complementary Expertise

Frank Jiang, MD, PhD Chairman, Chief Executive Asia Pacific U.S. Global Officer Head, R&D 21K Lovenox Mega Trial Phase 2 Trial

Jingrong Li, PhD Archie Tse, MD, PhD Jason Yang, MD, PhD Richard Yeh, MBA Bing Yuan, PhD, MBA Jon Wang, PhD SVP, Product Chief Translational Chief Medical Officer Chief Financial Officer Chief Business Officer Chief Scientific Officer Development & Medicine Officer Manufacturing

Managing Director Asia Pacific Healthcare Executive Director Clinical Development equity research lead analyst Executive Director & Global Director of Immuno-Oncology Early Clinical Development of SVP/Head Oncology BD Lead Research Immuno-oncology Keytruda Combo Partnership

Biotech sector research

Deep Manufacturing and Oncology Global Marketing Immuno-Oncology Research Senior Director Quality Expertise Drug research Clinical Development

4 Distinguished World-class Scientific Advisory Board With Deep Oncology and IO Expertise

Paul Bunn Elizabeth Jaffee Weiping Zou Richard Finn MD MD MD, PhD MD

AACR President Chair, AACR Cancer ASCO President International Liver Cancer 2018-2019 Immunology 2002-2003 Association Former President Professor of oncology, Charles B.de Nancrede Distinguished Professor, Clinical Professor, Johns Hopkins Professor, University of Colorado UCLA University University of Michigan

5 Synergized Oncology Portfolio Capturing Value in the Era of Combo Therapy

Molecular Lead Drug Target/ Indication(s) Drug Commercial IND Dose Partner Pre-clinical POC Pivotal NDA Candidate Signaling and Line(s) of Candidate Category Rights Filing Escalation Pathway Therapies Chemicals, 1 ivosidenib China Status R/R AML, 1L AML, (MRCT for AGILE); (CS3010, IDH1 Greater China NDA submission in Taiwan Cholangiocarcinoma Chemicals, 5.1 AG-120) US FDA Approved (Agios) (IND for R/R AML) R/R cHL, R/R NKTL, CS1001 China Status PD-L1 NSCLC7, Solid Biologics, 1 Worldwide (Core Product) Rest of the World Status tumors3 avapritinib PDGFRα/ 2L / 3L KIT & China Status (CS3007, GIST, Chemicals, 1 Greater China PDGFRα Pivotal Phase III trial in the US ongoing (Blueprint) BLU-285) AdvSM, ISM China StatusChina Status CS3009 1L / 2L NSCLC, RET Chemicals, 1 Greater China (BLU-667) 1L MTC5 Phase Ib trial in the US ongoing (Blueprint)

CS3008 China StatusChina Status FGFR4 1L / 2L HCC Chemicals, 1 Greater China (BLU-554) Phase Ib trial in the US ongoing (Blueprint) Clinical/IND China Status CS10022 CTLA-4 Solid tumors3 Biologics, 2 Worldwide Rest of the World Status China Status China Status CS10032 PD-1 Solid tumors3 Biologics, 1 Worldwide Rest of the World Status China Status CS30062 MEK Solid tumors3 Chemicals, 1 Worldwide Rest of the World Status Solid tumors3, China Status CS3003 HDAC6 Chemicals, 1 Worldwide R/R MM4 Rest of the World Status

CS3002 CDK4/6 Solid tumors3 Chemicals, 1 Worldwide Greater China, PD-L1/4- ND021 Solid tumors3 Biologics, 1 South Korea, 1BB/HSA Singapore CS3004 Worldwide

- clinical CS1009 Worldwide Undisclosed

Pre CS3005 Worldwide

CS2004 Worldwide

Source: Company 1 Some indication(s) may not require a non-pivotal Phase II clinical trial prior to beginning pivotal Phase II or III clinical trials. 2 Denotes we currently have clinical trials ongoing in Australia for the product candidate 3 Because there are no clinical efficacy data on the drug candidate, no specific types of solid tumors are established as lead indications at this stage. 4Available clinical data from other HDAC6 inhibitor studies provides the basis to suggest that CS3003 may be effective in treating MM; we plan to assess the clinical efficacy of CS3003 in MM and various types of solid tumor patients in the Phase Ib dose expansion trial. 5The clinical data published so far by Blueprint demonstrated that BLU-667 (CS3009) is effective in the treatment of certain NSCLC and MTC patients. Note: AML= Acute Myeloid Leukemia, AdvSM = Advanced Systemic Mastocytosis, cHL= Classical Hodgkin’s Lymphoma, GIST = Gastrointestinal Stromal Tumor, HCC = Hepatocellular Carcinoma, ISM = Indolent Systemic Mastocytosis, 6 NKTL = Natural KILLER/T Cell Lymphoma, NSCLC = Non-small Cell Lung Cancer, MTC = Medullary Thyroid Cancer, R/R = Relapsed or Refractory, SM = Systemic Mastocytosis, MM = Multiple Myeloma. Cancer Treatment Paradigm Shifts Towards Combo Therapy Given Significant Potential to Improve Survival and Response Rates COMBO THERAPY BELIEVED TO BE THE PARADIGM SHIFT TOWARDS COMBO MOST PROMISING CANCER TREATMENT THERAPY Improved overall survival and response rates1 Breakdown of PD-(L)1 trials by combination therapy / single-agent therapy2 IO Combo Therapy 26% % 72% SURVIVAL 74% Immune Checkpoint Therapy 28% Targeted Therapy Chemotherapy China US SURVIVAL DURATION Single Agent Combo Therapy

COMBINATION THERAPIES BASED ON PD-1/PD-L1 INHIBITORS AND CTLA-4 IO IS A FUTURE TREND SUPPORTED BY MABS HAVE BECOME THE MOST THERETICAL BASIS AND CLINICAL DATA ADOPTED IO BACKBONES PD-(L)1 combination trials globally, including Efficacy Response Rate Durability combination with CTLA-4

1716 1

2009 2018 Source: NMPA, Goldman Sachs Research, clinicaltrials.gov, Frost & Sullivan Analysis, Cell, literature research 1 For illustrative purpose only. Source: Cell, April 2015 (Sharma, Allison). 2 As of year-end 2017.

7 Large Scale and Right Mix of Pipelines to Drive Success in Combo Therapy

Numbers Right Mix and Large Scale COMBINATIONS INCREASE EXPONENTIALLY THE RIGHT BACKBONE ASSETS UNLOCK WITH NUMBER OF ASSETS COMBO POTENTIAL Only company in China which owns clinical stage PD-L1, PD-1 and CTLA-4 CStone # OF 15 Pipeline POTENTIAL Assets COMBOS CS1009 TIBSOVO® (CS3010) CS2004 (IDH1) # OF ASSETS

CS3009 CS3002 Cost Control (FGFR4) (CDK4/6) DEVELOPMENT & TREATMENT COST PD-L1 CONTROL

ND-021 In-house combo agents ensure (PD-L1x4-1BB) CS3008 CS3003 effective control of the (HDAC6) $ development and treatment cost (RET) PD-1 CTLA-4

Flexibility Avapritinib STAY AT THE FOREFRONT OF MEDICAL (CS3007) CS3004 (KIT&PDGFRα) ADVANCEMENT Rapidly adapt to the cutting edge CS3006 CS3005 therapeutic development and (MEK) focus on the most promising combination possibilities

8 Significant Potential to Multiply the Clinical Value with Rich IO and Other Oncology MOAs in Combo Therapies

Planned Trial Number By Type De-risked Combo Novel Combo - Unique to CStone CS1002 (CTLA4) + CS1001 (PDL1) + BLU554 CS1003 (PD1) (FGFR4) in HCC

CS1001 (PDL1) + ivosidenib CS1001 (PDL1) + VEGF (IDH1) in cholangiocarcinoma 10+ Pipeline 1.0 Pipeline CS1001 (PDL1) + PD(L)1 + CS3002 (CDK4/6) IMP4297 (PARP)

1

15+ Advanced Portfolio 10  Super-charge combo strategy based on PoC data 2018 2019  Novel molecular scaffolds & multi-specific antibodies Mono Combo  Cancer vaccines Pipeline 2.0 Pipeline  TME modulators

9 Four Highly Innovative Assets for Greater China: Two First-in-class and Two Potentially First-in-class

FIRST-IN-CLASS POTENTIALLY FIRST-IN-CLASS

CS3010 CS3007 CS3009 CS3008 (AG-120, Ivosidenib) (BLU-285, Avapritinib) (BLU-667) (BLU-554)

 IDH1m AML  GIST  RET-altered NSCLC  HCC Target Indication  IDH1m Cholangiocarcinoma  SM  RET-altered MTC

 IDH1m  KIT and PDGFRα  RET  FGFR4 Molecular Target

 The number of patients  The number of patients  The number of patients  The number of patients addressable by IDH1 addressable by KIT and addressable by RET addressable by FGFR4 inhibitors in China in 2017 PDGFRα inhibitors in China inhibitors in China in 2017 inhibitors in China in 2017 Market was ~1,600 for AML and in 2017 was ~20,900 for was ~11,300 for NSCLC was ~53,100 for HCC Opportunity ~6,900 for GIST and ~1,300 for SM and ~3,000 for MTC cholangiocarcinoma

 The first and only FDA-  Globally, there is no  Globally, there is no  Globally, there are approved1 therapy for marketed PDGFRα- marketed RET-selective currently no marketed patients with R/R AML and selective inhibitor inhibitor FGFR4 inhibitors, however First-in- an IDH1 mutation some FGFR4 inhibitor drug  The only PDGFRα inhibitor  Globally only two drug class candidates are undergoing  The only IDH1m inhibitor under clinical development candidates selectively clinical development Potential under clinical development in China targeting RET, BLU-667 and in China currently LOXO292 (by Loxo Oncology)

1. By Agios Pharmaceuticals. Note: AML = Acute Myeloid Leukemia; GIST = Gastrointestinal Stromal Tumor; SM = Systemic Mastocytosis; NSCLC = Non-small Cell Lung Cancer; MTC = Medullary Thyroid Cancer; HCC = Hepatocellular Carcinoma.

10 Achieved FPFD in BLU554 one month ahead of schedule; expect FPFD in the other 3 assets by 19Q3

Avapritinib BLU-667 BLU-554 Asset (KIT&PDGFRα) (RET) (FGFR4) (IDH1)

• Global FIC • Global FIC • Potentially Global FIC • Potentially Global FIC Highlight • US FDA approved • US FDA designations: • US FDA designation: • US FDA designations: Breakthrough therapy, Fast Breakthrough therapy Breakthrough therapy track for GIST and SM for NSCLC and MTC for IDH1m AML

Greater • Accepted for a China • Approved to join global • Approved to join global • Approved to join global China bridging study for R/R Ph3 trial for GIST in Ph1 trial for NSCLC and Ph1 trial for HCC IDH1m AML China MTC in China Status • Combo with PD-L1 IND • Approved to join global • Approved to initiate a • Consider to initiate approved in China Ph3 trial for 1L IDH1m China bridging study in Basket cohort in other • Achieved FPFD in HCC AML GIST with PDGFRα niche indications mono in May 2019 • NDA submission for R/R D842V mutation in AML in Taiwan in Jun China 2019, priority review status granted

Note: AML= Acute Myeloid Leukemia, SM = Systemic Mastocytosis, GIST = Gastrointestinal Stromal Tumor, HCC = Hepatocellular Carcinoma, NSCLC = Non- small Cell Lung Cancer, MTC = Medullary Thyroid Cancer, FIC = First-in-class, FPFD = First patient first dose 11 China’s First Full Human, Full-length IgG4 mAb: Proving Safe And Efficacious In Early Clinical Trials

 Designed with distinct characteristics: full human with potentially less ADA and tox  Potentially CStone’s first self-developed drug Overview to be approved in China  One of the first domestic anti-PD-L1 drugs to be launched in China  500+ patients dosed across 7 trials as of May 31, 2019

 Well tolerated and demonstrated good safety profile — Low infusion-related reaction — No DLT observed  #1: stage IV with lymph node metastases; 1200 mg Q3W — No Treatment-related SAE cervical cancer cohort; BOR is PR (SLD decrease of 69%, response was ongoing) — MTD not reached  #2: stage IV MSI-H ampullary carcinoma with retroperitoneal lymph node — Comparable AE profile metastases; 3 mg/kg Q3W cohort; BOR is PR (SLD decrease of 62%, Highlight response was ongoing)  Efficacy comparable to similar drugs  #3: stage IV NSCLC and adenocarcinoma with multiple extrathoracic — 24% ORR metastases; 20 mg/kg Q3W cohort; BOR is PR (SLD decrease of 57%, response was ongoing) — 7 confirmed PRs  #4: stage IV cholangiocarcinoma with liver and retroperitoneal lymph  PK profile showed concentration proportional node metastases; 20 mg/kg Q3W cohort; BOR is PR (SLD decrease of to dosage, with T½ of around 2 weeks 44%, response was ongoing) — ADA positive rate was 24%  #5: stage IV mixed histology of esophagus cancer and malignant melanoma with lymph node metastases; 1200 mg Q3W cohort; BOR is PR (SLD decrease of 32%, response was ongoing) Source: Company, presented at 2019 ASCO Note: PR = partial response; PK = Pharmacokinetic; ADA = anti-drug antibody; DLT = dose-limiting toxicity; SAE = serious adverse event; MTD = maximum tolerated dose; BOR = best overall response; 12 SLD = sum of longest diameters Comprehensive Winning Strategy for Our PD-L1 from Three Dimensions

1 FAST TO MARKET 2 MARKET OCCUPANCY MAXIMIZATION

Adaptive Trial Design 1st wave to launch in large indications1 covering 1.2 million of the cancer incidence in China

Sensitive / Niche Ranking in Cancer Indications Domestic Type Indication Treatment Competitors

Leverage Overseas Sites Consolidation therapy after chemoradiotherapy, PD-L1 ~1 Unresectable Stage III mono NSCLC 3 COMBO FLEXIBILITY NSCLC

AND POTENTIAL All comers, Stage IV PD-L1 1st Wave Our own NSCLC + SOC2 internal assets

Advanced HCC3 PD-L1 # OF PD-L1 HCC3 1st Wave 1L + SOC2 POTENTIAL combina- COMBOS tions

External Gastric assets PD-L1(+), GC PD-L1 st 2 1 Wave # OF ASSETS cancer 1L + SOC

Source: GBI; Clinicaltrials.gov; Frost & Sullivan analysis; Chinadrugtrials.org; press search; company websites 1 Advanced NSCLC, HCC, GC 2 SOC = Standard of Care 3 Company is evaluating both PD-L1 and PD1 as combo partner for this indication Note: NSCLC = Non-small Cell Lung Cancer; HCC = Hepatocellular Carcinoma; GC = Gastric Cancer 13 Robust Business Model Propelled by Our Clinical Development Engine, with Rapidly Developing Commercial and Manufacturing Capabilities

RESEARCH DEVELOPMENT COMMERCIALIZATION

Dual Sources of Overcoming Clinical Transitioning to Innovation Development Bottleneck Commercial Stage

Internal Unparalleled clinical In-house development development engine in China

Partnership Suzhou Translational Medicine Partnership Research Center

BUSINESS DEVELOPMENT

MANUFACTURING: “CMO + IN-HOUSE” APPROACH

14 Unparalleled Clinical Development Engine with a Proven Track Record

Frank Jiang, MD, PhD Jason Yang, MD, PhD Archie Tse, MD, PhD Chairman and CEO CMO CTMO

21,000 patient mega-trial Led numerous global and Over 20 years of global 79 clinical trials China trials; designed and oncology experience 30 NDA obtained conducted several PD-(L)1 Industry Leading Team and combos trials

Predefined Go/ Accelerate China Development FIH/ No-Go Criteria Pivotal 1/2 Time to Data Combo POC ✓ Accelerated Human Data Credibility Potential Approval vs. Conventional Internal Review and vs. Conventional: Ph I / Ph II US Planning Steps Transferability CLINICAL DEVELOPMENT Front-loaded Trial Design Streamlined, Parallel decision making Strategic Choice of Trial Location STRATEGY

Medical Science Pharmacovigilance Clinical Operation Biometrics

CLINICAL OPERATIONAL Seamless Operational Keep Strategy/ Oversight Outsource EXCELLENCE Collaboration Monitoring In-house Day-to-day Execution Activities

 Use biomarkers and preclinical discoveries to guide patient selection and predict treatment response in clinical trials  Increase success rate of clinical trials Pre- Clinical IN-HOUSE clinical TRANSLATIONAL RESEARCH CAPABILITY  Use clinical findings to guide preclinical discovery of drug resistance mechanisms

15 Translational Medicine Research Center in Suzhou (TMRC) – a part of our clinical development engine & a window to the world

Biomarker Drug Advanced Genomic Proven Drug data collection tools Discovery Discovery Discovery Platforms & & @CROs Translation Pipeline Research Support

Tissue banks & KOLs >1,000 Biotech & Expertise Pharma companies

Academic Breakthrough Bioinformatics Targets Capabilities Academic Labs

16 1 Dual Sourcing of Innovation Through Internal Development and External Partnership

External Internal Partnership Development

 Competitiveness

 Druggability

 Novelty

 Scientific rationale

 Clinical evidence

KOL R&D / Partnership Academia Database Literature Connections Meetings Network

17 1 Exclusive Regional Licensing Agreement For A Next Generation IO Therapy That Could Replace Current PD- (L)1 Therapies

ND021 tethers 4-1BB and activates T cells only upon engagement of PDL1-expressing tumor cells

Monovalent without Fc

Highlight • Potentially Best-in-class PD-L1/HSA/4-1BB tri-specific antibody-based molecule • Designed to significantly broaden safety window and higher efficacy vs current PD-(L)1 therapies • Validated dosing and longer half-life enable convenient dosing schedules vs competing molecules in the same class • Access to Numab’s novel multi-specific technology platform • Complement to CStone’s IO strategy

18 Pipeline 2.0 for Sustained Growth of CStone

Pipeline 1.0 GAP Analysis Pipeline 2.0

Balanced New Advanced Portfolio Targets (3-5 years) Portfolio De-risked Promising “practice changing”  I/O Backbone & Assets potential? FIC or BIC multispecific mAbs/scaffolds Convincing combo activity  TME modulators to Precision Medicine with PD-(L)1 or pipeline 1.0 maximize PD-(L)1 efficacy candidates?  Cancer vaccines Validated & Novel “Disruptive” biology?  Novel pathway inhibitors I/O Combination

Portfolio Prioritization  To build a world class multi-billion dollar oncology company, we must have a world class pipeline, know the gaps and fill them with innovative drug candidates for sustained growth;  Aim to deliver 1-2 IND each year

19 1 Partnership with Leading Biopharmaceutical Companies Globally

Well Positioned as Crown Jewel Assets from Leading Partner World Class Partners

 Enrich CStone oncology pipeline  Enable combo development

. Ivosidenib  FDA approved  Globally first-in-class

Partner-driven Innovation Engine Validated by High-profile Partnerships . Avapritinib “Best of Both Worlds“  Globally first-in-class . BLU-554 (FGFR4) Value Proposition . BLU-667 (RET)

 LARGE CHINA- Access to fast-growing but . ND021 complex China market  Next generation IO MULTINATIONAL CStone DOMICILED PHARMA PHARMA  Global quality and compliance  Potential BIC standard … More to come

20 Started Building Commercial Capabilities in China in Anticipation of Product Launches

Stage 3 2023+

Stage 2 2021-2023 Fully in-house in China and mostly in-house global Stage 1 2018-2021 Fully in-house in China

Small indication in China Highly innovative FIC products (Ivo, Ava) as the foundation, more concentrated, scientific and house - biomarker driven, well suited for In properly setting up a professional in- house team

Large indication in China and all Only ex-China Selectively ex-China indications ex-China First large potential and highly competitive product CS1001 (PD-L1), leverage partnership to maximize value and learn from partner Partnership

Mature asset or team Mature asset or team (opportunistic) Mature asset or team (opportunistic) (opportunistic) Buy mature asset / whole team (sales, Buy logistics, etc.) and executive to accelerate commercial set up

21 Hybrid Manufacturing Strategy for Both Small Molecules and Biologics

Hybrid Manufacturing Model

CMO Outsourcing Planned In-house Manufacturing Facilities

• Outsourcing the production of Small Molecules Biologics drug candidates to a limited number of industry-leading, highly reputable CMOs • To secure product supply for R&D needs and potential Compliance with GMP requirements product launches in China and globally • For ivosidenib (CS3010) and avapritinib (CS3007), we will import drug products from our licensing partners at the initial Planned capacity of biologics plant design: commercialization stage 10,000L (4x2,000L and 2x1,000L)

Drive Better Quality Efficient Down Win on Speed Stay Flexible Control Planning Cost

Stay Focused on Value Protection of Compliance Long-term Clinical Creation Key Know-how Monitoring Stable Supply Development

22 23

Record Breaking Financing by Prestigious Investors

2016/07 2018/05 2019/02

Record 1 Breaking HKEX IPO

2 Series B $328 Million Cornerstone Record investors Breaking1 $262 Million

Series A

$150 Million

Other global institutional investors (undisclosed)

Note:1At the time of the deal; 2Post-shoe

23 Legend • On track Near-term Catalysts • Update • New

PD-L1 Ivosidenib Avapritinib RET  Initiate 2 phase III trials (GC,  Initiate a registrational trial in  Initiate a China bridging study in  Initiate the China portion of a EC) in China and/or globally for China for the indication of 1L the indication of GIST with global trial in the indications of registration IDH1m AML by joining the global PDGFRa D842V mutation for RET fusion driven NSCLC, MTC study registration for registration  To publish clinical data at academic conference (ASCO,  Initiate a China bridging study in  Initiate the China portion of a  Consider to initiate Basket ESMO and CSCO) the indication of R/R IDH1m phase III trial in the indication of cohort in other niche indications AML for registration 3L GIST for registration  Initiate combo trial with PARP  File a China bridging study in the  Expect Blueprint to publish  Initiate combo trial with FGFR4 indication of IDH1m clinical data for GIST at Cholangiocarcinoma for academic conference (ASCO,  Initiate combo trial(s) with registration, pending partners’ CTOS) VEGFRi data  Expect Blueprint to publish  Expect to submit NDA in Q2 for clinical data for SM at academic R/R IDH1m AML in Taiwan conference (EHA, ASH)

 Potentially obtain IND approval for 2L GIST

2019

FGFR4 1. Initiate the China portion of a phase I trial (PoC) in the indication of HCC 2. Initiate a phase I trial (PoC) in the indication of HCC for FGFR4 in combo with PD-L1

PD-1 1. Expand clinical study into the US 2. To publish clinical data at ESMO annual meeting 3. Initiate a pivotal study in China based on data from phase I study (HCC or ES-SCLC)

CTLA-4 1. Initiate the dose escalation portion of combination with PD-1 in the ongoing Australian phase I study 2. Initiate phase I study in China in patients with advanced tumors

MEK 1. Initiate the dose escalation portion of combination with PD-1 in the ongoing Australian and China phase I studies 2. To publish clinical data at ESMO and CSCO

HDAC6 1. Initiate a phase I trial in patients with advanced solid tumors and multiple myeloma as monotherapy and combination with PD-(L)1 in China and Australia

CDK4/6 1. Initiate a phase I trial in patients with advanced solid tumors as monotherapy and combination with PD-(L)1 in Australia and China

24 Thank you! Press Releases since IPO Scientific Advisory Board  Appointed three distinguished oncology leaders Drs. Paul A. Bunn, Jr., Elizabeth M. Jaffee and Richard S. Finn to Scientific Advisory Board Business development  Exclusive regional licensing agreement with Numab for a next generation IO therapy that could replace current PD-(L)1 therapies CS1001 (PD-L1)  First patient dosed in Phase III GEMSTONE-303 study for CS1001 in combination with chemotherapy in first-line gastric adenocarcinoma and gastro-esophageal junction adenocarcinoma CS1003 (PD-1)  Presented pre-clinical data of CS1003 at the 2019 American Association for Cancer Research (AACR) Annual Meeting  Received IND approval in China for combination trial with CS3008 (FGFR4) CS3003 (HDAC6)  Received IND approval in China for HDAC6 inhibitor CS3007 (KIT & PDGFRα)  Received approval in China to join global phase III clinical trial for GIST CS3008 (FGFR4)  Dosed first patient in China as part of global phase I clinical trial in late stage HCC CS3009 (RET)  Received approval in China to join global phase I clinical trial for RET Inhibitor BLU-667 CS3010 (IDH1)  Agios received FDA Breakthrough Therapy designation for TIBSOVO® (ivosidenib) in combination with Azacitidine for the treatment of newly diagnosed acute myeloid leukemia (AML) with an IDH1 mutation in adult patients ineligible for intensive chemotherapy  Agios reported updated data from phase I study of ivosidenib in combination with Azacitidine demonstrating deep and durable responses in newly diagnosed IDH1 mutant acute myeloid leukemia (AML) patients  Agios announced FDA acceptance of supplemental New Drug Application for TIBSOVO® (ivosidenib) for the treatment of patients with newly diagnosed acute myeloid leukemia with an IDH1mutation not eligible for standard therapy  Agios Announces the Randomized Phase 3 ClarIDHy Trial of TIBSOVO® (ivosidenib) Achieved its Primary Endpoint in Previously Treated IDH1 Mutant Cholangiocarcinoma Patients 26