CSTONE PHARMACEUTICALS (2616.HK) COMPANY PRESENTATION

June 2021 Presentation Disclaimer

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2 Overview 2 3 4 5 6 7

To become a world-renowned biopharmaceutical company that is leading the way to conquering cancer

HKEx listed Full-fledged Biopharma 2616.HK 5 Years Since Company Inception

$150M $262M $328M Series A Series B HK IPO (Feb 2019) Industry-leading (July 2016) (May 2018) management team $200M Pfizer strategic investment (Sep 2020) Well-balanced Integrated commercial stage biopharma $150M oncology portfolio with a focus with clear focus on clinical on immuno-oncology and Collaboration with EQRx development, fast ramp-up of precision medicine with 5 NDA (Oct 2020) manufacturing capability, and approvals and 5+ NDA filings full-fledged commercial expected in 2021 capabilities

Note: NDA = New Drug Application 3 Overview 2 3 4 5 6 7 Industry leading management team with proven track record and complementary expertise

Frank Jiang, MD, PhD Chairman, Chief Executive Officer Former VP, Head of APAC R&D at Sanofi

Shirley Zhao, MD, MBA Jason Yang, MD, PhD Archie Tse, MD, PhD Greater China GM, Chief Medical Officer Chief Scientific Officer Head of Commercial Former SVP, Head of Former Executive Director of Former GM of BMS China Clinical Development at Oncology Clinical Research Beigene at MSD

Sanhu Wang, MPH Michael Choi, MBA Jingrong Li, PhD SVP, Government and Chief Business Officer Chief Technology Officer Regulatory Affairs Former VP, head of BD Former Executive Director Former Deputy at SPARC at Simcere Director at CFDA

4 Overview 2 3 4 5 6 7 Well-balanced oncology portfolio of 15 innovative assets Focused on immuno-oncology and precision medicine

Lead Indication(s) Dose Drug Candidate Rights Pre-clinical POC Pivotal NDA Partner and Line(s) of Therapies Escalation

Pralsetinib 1L / 2L NSCLC, Mainland China NDA approved (RET) MTC / TC

stage Avapritinib PDGFRA exon 18 GIST, Mainland China and Taiwan NDA approved, Hong Kong NDA accepted

Commercial (KIT / PDGFRA) AdvSM, ISM

Sugemalimab NSCLC, GC, ESCC Out-licensed Mainland China NDA submitted (CS1001, PD-L1) R/R NKTL Mainland China Ex-Greater China Ivosidenib R/R AML, 1L AML, Expecting to submit NDA in mainland China in 2021 (IDH1) Cholangiocarcinoma

stage CS1003 - HCC (PD-1) Ex-Greater China

Late Lorlatinib NSCLC (ROS1) Co-development in Greater China Fisogatinib 1L / 2L HCC (FGFR4) CS1002 Solid tumors (CTLA-4) CS2006 Solid tumors (PD-L1/4-1BB/HSA) CS3002 Solid tumors

(CDK4/6) Clinical/IND CS3005 Solid tumors (A2aR)

CS5001 Solid tumors, * (ROR1) hematologic cancers CS2007 Undisclosed

(Multi-Specific) clinical

- CS2008 Undisclosed

(Multi-Specific) Pre CS5002 Undisclosed (ADC) Source: Company Note: Assets status denote progress in the region noted in the column titled “Rights”. Global China Korea Singapore * CStone obtains the exclusive global right to lead development and commercialization of LCB71 outside the Republic of Korea POC = Proof of Concept, NSCLC = Non-small Cell Lung Cancer, MTC = Medullary Thyroid Cancer, TC = Thyroid Cancer, GIST = Gastrointestinal Stromal Tumor, AdvSM = Advanced Systemic Mastocytosis, ISM = Indolent Systemic Mastocytosis, GC = Gastric Cancer, ESCC = Esophageal Squamous Cell Carcinoma, R/R = Relapsed or Refractory, NKTL = Natural KILLER/T Cell 5 Lymphoma, AML= Acute Myeloid Leukemia, HCC = Hepatocellular Carcinoma 1 Products 3 4 5 6 7 Remarkable speed towards commercialization Expect 5 NDA approvals for 4 products in 2021, 3 approvals secured

泰吉华® 普吉华® Avapritinib Ivosidenib Sugemalimab Pralsetinib (KIT/PDGFRA （IDH1 inhibitor) (PD-L1 antibody) (RET inhibitor) inhibitor)

2L RET fusion- PDGFRA exon 18 / IDH1 1L Stage IV NSCLC positive NSCLC D842V mutant GIST r/r AML (sq & nsq)

Mainland China Mainland China Mainland China Mainland China Taiwan, China

Commercialized by Commercialized by

Launched Launched 6 Note: NSCLC = Non-small Cell Lung Cancer, GIST = Gastrointestinal Stromal Tumor, AML= Acute Myeloid Leukemia, r/r = relapsed or refractory, sq = squamous, nsq = non-squamous 1 Products 3 4 5 6 7 Pralsetinib: first-in-class RET inhibitor in China CStone’s first approved therapy; multiple NDA filings expected in 2021

2L RET fusion-positive NSCLC 1L RET fusion-positive NSCLC 2L RET fusion-positive NSCLC Mainland China Mainland China Taiwan, China

Launched NDA filing planned in 2H 2021 NDA filing planned in 2H 2021

RET-mutant MTC RET fusion-positive TC Basket cohort Mainland China Mainland China Mainland China

NDA accepted in March 2021 with NDA accepted in March 2021 with Broad indications beyond NSCLC BTD and priority review priority review / TC

80,000+ newly diagnosed incidences, including ~45,000 addressable patients, per year harboring RET mutation in China*

Launched in Bo’ao, China in Sept 2020, enabling prescriptions in parallel with US

The ONLY 2L+ therapy recommended by 2021 Chinese Medical Association Guidelines for RET fusion-positive stage IV nsq NSCLC

Testing for RET alteration recommended by 2021 Guidelines on Clinical Practice of Molecular Tests in NSCLC in China (level I recommendation)

7 Note: Globocan 2020, CStone analysis NSCLC = Non-small Cell Lung Cancer, MTC = Medullary Thyroid Cancer, TC = Thyroid Cancer, BTD = Breakthrough Therapy Designation, nsq = non-squamous 1 Products 3 4 5 6 7 Avapritinib: first-in-class KIT/PDGFRA inhibitor in China NDA approvals granted by NMPA and TFDA

PDGFRA ex 18 GIST PDGFRA D842V GIST PDGFRA D842V GIST Mainland China Taiwan, China Hong Kong, China

Launched Launched NDA accepted in May 2021

Advanced Systemic Mastocytosis Indolent Systemic Mastocytosis Mainland China Mainland China

Approved in U.S. and exploring Global pivotal trial ongoing and expedited registrational pathway exploring expedited registrational for China market pathway for China market

~40,000 newly diagnosed incidences per year harboring PDGFRA exon 18 and/or KIT exons 9/11/13/14/17 mutation in China*

Launched in Bo’ao, China in September 2020

Recommended by CSCO Guidelines for GIST treatment (level II recommendation for both PDGFRA D842V mutant GIST and 4L GIST patients)

Note: Globocan 2020, CStone analysis 8 NMPA = National Medical Products Administration, TFDA = Taiwan Food and Drug Administration, GIST = Gastrointestinal Stromal Tumors, SM = Systemic Mastocytosis 1 Products 3 4 5 6 7

Ivosidenib: global first-in-class IDH1 inhibitor No immediate competitor in China; significant indication expansion potential

IDH1m R/R AML IC-Ineligible 1L AML IDH1m Cholangiocarcinoma Mainland China Mainland China Mainland China

U.S. NDA filing accepted for NDA filing and approval Registrational study previously treated IDH1 mutant expected in 2H 2021 cholangiocarcinoma

~35,000 newly diagnosed incidences per year harboring IDH1 mutation in China*

Included in the list of drugs of urgent clinical need in China, indicating accelerated reviewing process with technical review within 70 business days

Recommended by CSCO Guidelines for treatment of malignant hematological disease (level II recommendation for IDH1 mutant R/R AML patients)

Note: Globocan 2020, CStone analysis 9 AML= Acute Myeloid Leukemia, R/R = Relapsed or Refractory, IC = intensive chemotherapy 1 Products 3 4 5 6 7

Sugemalimab: best-in-class anti-PD-L1 mAb (1/3) First NDA approval expected in 2021 and multiple NDA filings in 2021 / 2022

■ Outstanding efficacy: • The first PD-L1 in combo with chemo to demonstrate Best-in-Class clinical efficacy in both squamous and non-squamous Stage IV NSCLC with a PFS HR of 0.5 • The first PD-L1 to demonstrate outstanding clinical efficacy in Stage III NSCLC following either concurrent chemoradiation treatment (cCRT) or sequential CRT (sCRT) Best-in-class potential • Superior clinical efficacy also observed in other cancer types, including ESCC, GC, R/R ENKTL, etc. “Breakthrough Designation” granted by both FDA and CDE

■ Differentiated design: Fully-human, full length IgG4 derived from Ligand’s OmniRat® platform – minimalizing ADA occurrence; retaining ADCP activity for better efficacy ■ Highly favorable safety profile: 1,600+ patients dosed* as mono or combo-therapy

Broad ■ The only PD-(L)1 worldwide to cover both Stage III and Stage IV NSCLC, as well as GC, coverage ESCC and R/R ENKTL

The most studied PD-L1 in China: 5 registrational trials ongoing

Indication Last patient in NDA filing NDA approval

• 1L Stage IV NSCLC May 2020 Nov 2020 2H 2021*

Multiple NDA • Stage III NSCLC Dec 2020 2H 2021* 2022* filling plans • 1L GC 2H 2021* 2022* 2023*

• 1L ESCC 2H 2021* 2022* 2023*

• R/R ENKTL (Mainland China) 1H 2021* 2022* 2022/2023*

• R/R ENKTL (US) 1H 2021* 2022* 2022/2023*

Note: * As of Dec 31, 2020, including patients dosed with placebo; mAb = monoclonal antibody, ADA = anti-drug antibodies, IgG4 = Immunoglobulin G4, NSCLC = non-small cell lung cancer, ESCC = Esophageal Squamous Cell Carcinoma, GC = Gastric Cancer, R/R = Relapsed or Refractory, ENKTL = Extranodal Natural KILLER/T Cell Lymphoma, cCRT 10 = concurrent chemoradiotherapy, sCRT = sequential chemoradiotherapy 1 Products 3 4 5 6 7 Sugemalimab: best-in-class efficacy demonstrated at interim analysis, and confirmed by final analysis (2/3) Efficacy and safety profile in 1L Stage IV NSCLC at interim analysis

PFS Benefit: Reduction of the Risk of Disease Progression or Death (%) 60 50 52 PD-L1 PD-1 48 50 46 48 44 40 39 40 36 36 29 PD-(L)1 for 1L 30 treatment of 20 Stage IV NSCLC 10

(sq & nsq) 0 Sugemalimab Durvalumab Atezolizumab Pembrolizumab Camrelizumab Sintilimab Tislelizumab CStone AstraZeneca Roche Merck Hengrui Innovent BeiGene sq&nsq sq&nsq sq nsq nsq sq nsq nsq sq nsq sq nsq IMpower IMpower IMpower RATIONALE RATIONALE GEMSTONE-302 POSEIDON* Keynote-407 Keynote-189 SHR-1210-303 ORIENT-12 ORIENT-11 131 130 132 307 304 Not Not Under Under Under review Not approved Approved Approved Approved Approved Approved Approved approved approved review review

Comparison of irAE rate between sugemalimab and pembrolizumab (%) 9 CS1001-302 (sq&nsq) Keynote-189(nsq) Keynote-407(sq) 8 7 6 Favorable 5 safety profile of 4 sugemalimab 3 2 1 0 HypothyroidismHypothyroidism HyperthyroidismHyperthyroidism HepatitisHepatitis PneumonitisPneumonitis Severe skin skin ThyroiditisThyroiditis DiabetesDiabetes mellitus NephritisNephritis MyocarditisMyocarditis ArthritisArthritis ColitisColitis HypophysitisHypophysitis Pancreatitis ArenalAdrenal MyositisMyositis adverseadverse reactions mellitus insufficiencyinsufficiency reactions * irAE defined based on a list of preferred terms specified by the sponsor and were included in the analysis regardless of whether they were attributed to treatment by the investigator

Note: * PFS HR data of POSEIDON trial not publicly available; cross trial comparison subject to the usual caveat; NDA status as of Mar 1st, 2021; NSCLC = non-small cell lung cancer, sq = squamous, nsq = non-squamous 11 Source: public information and CStone analysis 1 Products 3 4 5 6 7 Sugemalimab: outstanding efficacy demonstrated in Stage III NSCLC at interim analysis (3/3) The first PD-L1 to demonstrate clinical efficacy in both Stage III and IV NSCLC

Strategic Significance Significant unmet need with high incidence

• World’s first PD-(L)1 to successfully 2020 stage III NSCLC incidence improve PFS in stage III NSCLC not progressing after either concurrent or sequential chemoradiotherapy ~163k ~131k (China) (US/Japan/EU5*) • World’s first PD-(L)1 for the treatment of both stage III and stage IV NSCLC

• NDA filing to NMPA for stage III NSCLC expected in 3Q 2021. 2020 stage IV NSCLC incidence Regulatory discussions in multiple countries, including U.S., planned for both stage III and stage IV NSCLC ~322k ~208k (China) (US/Japan/EU5*)

China NDA filing expected in 3Q 2021, ex-China regulatory discussions planned

Source: Clarivate DRG 12 Note: UK, Germany, France, Italy and Spain 1 Products 3 4 5 6 7 CS1003 (PD-1): Another I/O backbone in registration study Global Ph3 in HCC supported by compelling PoC data

■ Humanized IgG4 anti-PD-1 mAb Asset ■ Recognizes both human & murine PD-1 with unique advantage to evaluate efficacy in overview syngeneic mouse models, esp. for testing combinations with small molecules

■ Bridging Ph I conducted in China showed that CS1003 monotherapy was safe and tolerable at 60mg and 200mg Q3W; no DLT or MTD was observed (N=19)

■ Ph Ib data showed that ORR and mPFS reached 40% and 8.4 months respectively among 20 HCC patients that received the treatment of CS1003 + Lenvatinib Preliminary efficacy of CS1003 + lenvatinib in HCC Strong PoC data & global Ph3 in HCC

■ A global randomized Ph III trial of CS1003 + lenvatinib in first line treatment for advanced unresectable HCC (CS1003-305) is ongoing

Significant ■ I/O backbone with multiple combo studies ongoing, including the study of CS1003 development + CS1002 (CTLA-4) progress

13 Note: DLT: dose-limiting toxicity； MTD: maximum tolerated dose; Q3W: once every 3 weeks; PK: pharmacokinetics; ADA: anti-drug antibody; PR: partial response; VEGF: vascular endothelial growth factor; TKI: tyrosine kinase inhibitor; HCC: hepatocellular carcinoma 1 2 Commercial 4 5 6 7 Renowned commercial leadership team

Seasoned leaders with diverse range of experience at multinational biopharmas and innovative biotechs

Shirley Zhao Greater China GM, Head of Commercial Operations

Sophia Lee Yanchu Lu Zezhou Wang TW & HK Marketing Sales Strong track record with 20+ successful launches in oncology & hematology

Philip Chen Jason Zhang Michael Qiao Broad Market Medical Affairs Business Access Excellence 14 1 2 Commercial 4 5 6 7 Full-fledged commercial team established Ready to ensure successful launches in 2021

4 Oncology therapeutic areas

Provide >300 >400 comprehensive * Hospital coverage FTE coverage

~100 YE2019 YE2020 YE2021 City coverage

Comprehensive coverage with a well-established commercial team will ensure readiness for precision medicine launches, and our ability to capture the significant market potential

Note: FTE = Full Time Equivalent 15 1 2 Commercial 4 5 6 7 Clear commercial strategy to maximize product value

Patient Commercial Market Branding identification capability access

▪ Develop and deliver ▪ Establish mindset of ▪ Build a strong sales ▪ Drive Bo’ao EAP pilot to clear & precise message gene testing driven team to reach critical pave the way for on avapritinib, pralsetinib therapy mass successful launch in & ivosidenib value Mainland China proposition to patient in ▪ Standardize current ▪ Enhance promotion & Greater China & diagnosis & treatment commercialization ▪ Ensure access to target Singapore with specific pathway capability to maximize hospitals and patients mutation commercial value w/ PAP and other ▪ Build scientific innovative solutions ▪ Drive strong brand leadership to achieve awareness via KOL differentiation via data ▪ Maximize accessibility engagement activity, publication, real-world & via NRDL listing in 2021 event & launch campaign retrospective studies

Note: KOL = Key Opinion Leader, EAP = Early Access Program, NRDL = National Reimbursement Drug List, PAP = Patient Assistance Program 16 1 2 3 BD 5 6 7 Strategic and multi-dimensional collaboration with Pfizer

Equity investment: $200mm (at ~HK$13.37 / share)

1 2 3 China commercialization of Co-development of Joint in-licensing of global sugemalimab Pfizer’s assets innovative drugs In addition to the equity investment ▪ Two post proof-of-concept ▪ Jointly in-license for Greater China premium, CStone is entitled to receive oncology assets, potentially market Up to $280mm in milestone those already launched in US ▪ ▪ CStone retains option to payments, and ▪ CStone to receive low double- participate in co-promotion ▪ Tiered, mid-to-high teens royalties digit royalties

Pfizer CStone ◼ A global pharmaceutical leader with ◼ An emerging leader in the prestigious brand value biopharmaceutical industry in China ◼ Extensive commercialization ◼ Sugemalimab, a commercial-ready, network in China potential best-in-class PD-L1 asset for large indications ◼ Leading oncology franchise with robust pipeline of drug candidates ◼ Superior clinical capabilities with strong execution

Synergistic Collaboration Long-term collaboration Faster and broader Competitive platform for in- solidified through equity commercialization of licensing deals to allow investment sugemalimab in China rapid expansion of pipeline

17 1 2 3 BD 5 6 7 Global out-licensing deal with top-notch biotech EQRx

CStone to out-license ex-China rights to EQRx for two key late-stage assets, sugemalimab (PD-L1) and CS1003 (PD-1) ▪ EQRx will lead clinical development and commercialization of these two assets outside of Greater China ▪ CStone to receive US$150m upfront payment, up to US$1.15bn

milestone payments and tiered royalties on net sales

Maximize global ▪ EQRx’s innovative business model to position CStone’s assets competitively in large indications commercial potential of ▪ EQRx’s exceptionally experienced “all-star” team with stellar track record of success two lead I/O assets ▪ Broad potential for CStone to pursue CS1003 drug combos for the China market

Meaningful

▪ Immediate and significant capital proceeds to invest in strategic initiatives, as we transition into a immediate financial fully integrated biopharma and pursue CStone Pipeline 2.0 strategy benefits

Proof of global ▪ Builds on CStone’s successful track record of forming strategic partnerships business development capabilities ▪ Elevates CStone as a partner of choice for global biotech and biopharma

Importance for ▪ Make CStone’s assets available to global patient community patient community ▪ EQRx’s innovative business model to enlarge access and make drugs more affordable for patients

18 1 2 3 BD 5 6 7 Engagement with partners to maximize I/O asset value

>300 >2,600 >1,000 Cities with business Hospital Field force in operations coverage China

11 oncology products covering 5 major therapeutic areas Abundant experience in NRDL negotiation

▪ Joint working model: Regular working ▪ Innovative Go-To-Market model: We group meetings scheduled on registration, aligned w/ EQRx on regulator engagement & supply, medical and marketing to ensure NDA filing strategies for possible cost-efficient, successful collaboration fast-to-market routes in the US, UK & EU

▪ Brand plan and launch: launch team built ▪ Positive “proof-of-concept” feedback: up, brand launch plan developed and EQRx has explored and validated the undergoing fine-tuning through extensive potential of sugemalimab with key marketing research stakeholders based on interim data of stage IV NSCLC ▪ Supply chain readiness: product demand order prepared & supply route designed to ensure fast launch once approved

19 1 2 3 BD 5 6 7

Joint development of Lorlatinib with Pfizer to further deepen our multi-dimensional strategic partnership

Strategic Significance Significant unmet need with high incidence

• Strengthened collaboration built on the strategic partnership reached Sizable patient population between CStone and Pfizer in 2020 • Over 670K diagnosed incidence of NSCLC in China, • CStone chose this asset to leverage 2-3% of which are ROS1+ strong synergies with our lung franchise and huge potential to address the urgent unmet medical Limited treatment options needs • Only 1 TKI approved for • Leverage CStone’s robust clinical ROS1+ lung cancer in China development capabilities and Pfizer’s • No approved targeted leading commercialization capabilities to therapies in TKI refractory accelerate and maximize market setting potential of Lorlatinib • Limited efficacy of existing treatment for patients with • World’s first pivotal study of Lorlatinib brain metastases on ROS1 in TKI refractory setting

Source: Clarivate DRG; Zhang et al. Prevalence of ROS1 fusion in Chinese patients with non small cell lung cancer, Thorac Cancer 2019 10(1): 47–53. 20 1 2 3 4 Pipeline 2.0 6 7 Pipeline 2.0: CStone-driven innovation model Primarily focus on global FIC/BIC/FW assets in emerging therapeutic categories

I/O (Combo) & Precision Medicine

1 Idea Generation FIC/BIC/FW Examples CStone-Driven Project Design • 2 ADCs, incl. CS5001 Innovation 2 Global rights • 3 multi-specifics, Work with CRO Model incl. CS2006 on execution 3 1~2 INDs/yr

Archie Tse, MD, PhD Sources of Innovative Ideas Chief Scientific Officer

• Physician-scientist with 20+ years of Project Protein Chemistry Pharmacology Clinical experience in translational oncology Management BD Observa- research covering cytotoxics, targeted partners agents, and immunotherapies DMPK / Clinical tions • Oncology TA Head at Daiichi-Sankyo Toxicology Pharmacology responsible for the development and implementation of overall Oncology TA Bioinformatics Translation Molecular Med/Biomarker Diagnostics CRO strategy Academic SAB • Oversaw early development of 14 IO platforms assets of different MOAs and Early Development modalities at MSD

Line of sight from Discovery Research to PoC under a single leadership 21 Note: I/O = immuno-oncology, TME = tumor microenvironment, ADC = antibody-drug conjugate, FIC = first-in-class, BIC = best-in-class, FW = first wave, PoC = Proof of Concept 1 2 3 4 Pipeline 2.0 6 7 Advancing Pipeline 2.0 development Multiple first-in-class / best-in-class molecules

▪ We have secured the global rights to multiple innovative molecules with first-in-class / best-in-class potential ▪ Modular and multi-functional ADCs and multi-specific molecules advance our portfolio towards Pipeline 2.0

1 CS5001 / LCB71 (ROR1 ADC) 2 CS5002 (ADC) • Global rights (outside Korea) • Global rights ADCs • Potential BIC ROR1 ADC with • Potential BIC molecule differentiated technology • CStone self-designed and • In-licensed from LegoChem proprietary And more…

CS2006 / NM21-1480 CS2007 CS2008 1 2 3 (PD-L1 x 4-1BB x HSA) (Multi-Specific) (Multi-Specific) • Rights in Greater China, • Global rights • Global rights Korea and Singapore • Global FIC • Global FIC Multi-specific • Tri-specific molecule with the molecules • CStone self-designed • CStone self-designed potential to be BIC molecule and proprietary and proprietary as the next generation PD- (L)1 inhibitor • In-licensed from Numab And more…

Others And more…

22 1 2 3 4 Pipeline 2.0 6 7 CS5001: Potential first-wave/best-in-class ROR1 ADC Broad tumor coverage with potentially improved efficacy and reduced toxicity

CStone acquired global development & commercialization rights (ex-Korea)

Asset Highlights

▪ A potential global first-wave / best-in-class drug with four key differentiators: − Fully human mAb v.s. humanized mAb in VLS-101 and NBE-002 − Site-specific conjugation for a homogeneous drug antibody ratio (“DAR”) (DAR=2) − Proprietary tumor-selective cleavable linker, highly stable in serum − Tumor-activated pyrrolobenzodiazepine (“PBD”) dimer toxin prodrug to address PBD payload systemic exposure toxicity ▪ Potential monotherapy and combination applications for multiple solid and hematological malignancies including lung, breast, ovarian cancers, leukemia and NHL, where ROR1 is prevalently expressed

Accelerated Development Timeline

▪ IND submission for CS5001 expected in 2H 2021, roughly one year following BI’s program

Other Recent Transactions for ROR1 ADC Asset Development stage Indications Global value VLS-101 ▪ Ph I/II ▪ TNBC, NSCLC, • In Nov 2020, Merck acquired (Merck / VelosBio) ▪ Global first-in-class CLL and MCL, etc. VelosBio $2.75bn for all shares NBE-002 ▪ Entered Ph I in Oct 2020 ▪ TNBC and • In Dec 2020, Boehringer Ingelheim (BI / NBE advanced solid acquired NBE Therapeutics for Therapeutics) tumor, etc. ~$1.4bn (Euro 1.18bn) for all shares

Note: NHL=non-Hodgkin lymphoma, TNBC = Triple Negative Breast Cancer, NSCLC = Non-Small Cell Lung Cancer, CLL = Chronic Lymphocytic Leukemia, MCL = Mantle Cell 23 Lymphoma 1 2 3 4 Pipeline 2.0 6 7 CS2006 (PD-L1x4-1BBxHSA): potential BIC 4-1BB agonist and next generation PD-(L)1 inhibitor

Asset Highlights

▪ A potential best-in-class drug with special design to reduce unwanted toxic effects and Next improve therapeutic index − Unique monovalent 4-1BB binding conditionally activated upon PD-L1 Generation engagement PD-(L)1 − Sophisticated affinity-balancing between PD-L1 & 4-1BB ▪ Expansive array of potential combo options as a new I/O backbone

Accelerated Development Timeline

▪ US FDA IND application “may proceed” letter received 2Q 2020, TFDA IND approval received 3Q 2020 ▪ US/Global FIH dose escalation study ongoing; Dose level 4 enrollment completed, no DLT identified so far ▪ TW site activated in 1Q 2021 ▪ IND submission to NMPA expected in 2H 2021

Other Key Differentiation of CS2006

▪ Ultra high affinity of αPD-L1 potentiates broader PD- PD-L1 Negative L1 tumor types and lower demanding of PD-L1 level CHO Cancer ▪ No impact on endogenous 4-1BB-4-1BBL binding to preserve normal antigen presentation PD-L1 scMATCH3 ▪ αHSA domain extends the T1/2 & avoids undesirable PD-1 scMATCH3 PD-1 Fc-FcγR interaction 4-1BB 4-1BB PD-L1 Positive ▪ MW~80 KD (vs. mAb ~150KD) increases tumor urelumab penetration T cell Urelumab CS2006 T cell

24 Note: BIC = best-in-class, FIH = first-in-human, TFDA = Taiwan Food and Drug Administration, DLT = dose-limiting toxicity 1 2 3 4 5 Manufacturing 7 State-of-the-art manufacturing facility in construction Pilot operation expected in 2021

◼ Manufacturing facility built in collaboration with Sungent (state-owned controlled by Suzhou Industrial Park)

◼ Integrated capabilities for R&D, pilot plant, and full commercial scale manufacturing

◼ Planned building capacity area of approximately 100,000 sqm

◼ 26,000L for biologics and 1 billion tablets / capsules for small molecule drugs

◼ Commencement of construction in the first Small Molecules Biologics half of 2020 with pilot operation in 2021

◼ Release test methods validation for Compliance with GMP requirements sugemalimab to be completed by 2021 as in China and globally part of the technology transfer

◼ Strategic partnership with Wuxi Biologics on Planned capacity of biologics plant design: clinical / commercial stage manufacturing 26,000L for biologics and 1 billion tablets for small molecules

Drive Better Quality Efficient Down Control Planning Cost

Value Protection of Compliance Long-term Creation Key Know-how Monitoring Stable Supply

25 1 2 3 4 5 6 Outlook Completing transition to full-fledged biopharma A full agenda for 2021 to build on last year’s significant achievements

Imminent and robust commercialization activity Expect 5 NDA approvals in total, an industry-leading amount 3 approvals for pralsetinib and avapritinib received; 2 others pending

Expediting full slate of clinical development programs NDA filings1 and data readouts2 for additional indications, with trials by 5+ 4 30

year-end, including 15 for registration

Harvesting benefits from strategic collaboration with Pfizer Nominate at least one post proof-of-concept oncology asset for co-development, potentially one already launched in US

Elevating Research and bolstering Pipeline 2.0 Focus on global FIC/BIC molecules with 2 IND filings expected

Near-term launch of pilot manufacturing operations On track with the construction of a state-of-the-art facility in Suzhou; anticipate launching pilot operations this year

Note: 1. Expected NDA filings include but not limited to (1) sugemalimab: stage III NSCLC in mainland China; (2) pralsetinib: 1L NSCLC in mainland China; (3) pralsetinib: RET mutant MTC and RET fusion-positive TC in mainland China; (4) pralsetinib: 2L NSCLC in Taiwan; (5) ivosidenib: r/r AML in mainland China 26 2. Expected data readout include (1) sugemalimab: stage III NSCLC; (2) pralsetinib: 1L NSCLC; (3) pralsetinib: 1L MTC; (4) ivosidenib: r/r AML 1 2 3 4 5 6 Outlook A defined commercialization roadmap beyond 2021

Snapshot of launch roadmap for our current pipeline with expansion potential from the development of new assets

Near-term (2021) Mid-term (2022~2025) Longer-term (2026~)

Expect 11+ potentially approved products Across 21+ indications1 Avapritinib Pralsetinib PDGFRA exon 18 GIST, RET 1L / 2L NSCLC, 1L AdvSM, ISM MTC / TC and others Ivosidenib Lorlatinib IDH1 r/r AML, 1L AML, ROS1 NSCLC Expect 7+ products CCA 1 Fisogatinib CS3005 CS3002 Across 15+ indications HCC （A2aR） （CDK4/6） Pralsetinib Avapritinib RET 1L NSCLC, Sugemalimab PDGFRA exon 18 GIST, RET 2L NSCLC, Stage IV NSCLC (sq & CS1003 (PD-1) AdvSM, ISM Expect 4 products 1L MTC / TC nsq), Stage III NSCLC, HCC ESCC, GC, NKTL 1 Across 4+ indications Ivosidenib Sugemalimab CS2006 IDH1 r/r AML, Stage IV NSCLC (sq & CS5001 CS1002 nsq), Stage III NSCLC, (PD-L1/ 4-1BB/ 1L AML (ROR1 ADC) (CTLA-4) Avapritinib Pralsetinib ESCC, GC, NKTL HSA) PDGFRA exon 18 GIST RET 2L NSCLC Fisogatinib CS1003 (PD-1) Molecules from co-development and joint in- HCC HCC licensing with Pfizer Sugemalimab Ivosidenib Other molecules from Stage IV NSCLC (sq & Lorlatinib More molecules under co-development or in- IDH1 r/r AML co-development with nsq) ROS1 NSCLC licensing agreement with partners Pfizer Small Details to be Biologics molecules disclosed Note:1. For in-licensed assets NDA approval time will depend on our partners’ NDA approval time by US FDA GIST = Gastrointestinal Stromal Tumor, AML= Acute Myeloid Leukemia, R/R = Relapsed or Refractory, NSCLC = Non-small Cell Lung Cancer, sq = squamous, nsq = non-squamous, MTC = Medullary Thyroid Cancer, TC = Thyroid Cancer, AdvSM = Advanced Systemic Mastocytosis, ISM = Indolent Systemic Mastocytosis, HCC = Hepatocellular Carcinoma, NKTL = Natural KILLER/T Cell Lymphoma, 27 ESCC = Esophageal Squamous Cell Carcinoma, GC = Gastric Cancer, CCA = Cholangiocarcinoma Thank you