IDEAYA Biosciences : Corporate Presentation - August 2020

August 2020

NASDAQ: IDYA

IDEAYA Biosciences

Improving Lives

Through Transformative

Precision Medicines

Safe Harbor Statement

Certain statements in this presentation and the accompanying oral commentary are forward-looking statements. These statements relate to future events or the future financial performance of IDEAYA Biosciences, Inc. (the "Company") and involve known and unknown risks, uncertainties and other factors that may cause the actual results, levels of activity, performance or achievements of the Company or its industry to be materially different from those expressed or implied by any forward-looking statements. In some cases, forward-looking statements can be identified by terminology such as "may," "will," "could," "would," "should," "expect," "plan," "anticipate," "intend," "believe," "estimate," "predict," "potential" or other comparable terminology. All statements other than statements of historical fact could be deemed forward-looking, including any expectations regarding the Company's target discovery platform or new target validation efforts as creating opportunities for research and development initiatives; any projections of financial information, market opportunities, cash runway or profitability; any statements about historical results that may suggest trends for the Company's business; any statements of the plans, strategies, and objectives of management for development programs or future operations; any statements about the timing of preclinical research, clinical development, regulatory filings, manufacturing or release of data; any statements of expectation or belief regarding future events, potential markets or market size, or technology developments; and any statements of assumptions underlying any of the items mentioned. The Company has based these forward-looking statements on its current expectations, assumptions, estimates and projections. While the Company believes these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond the Company's control. These and other important factors may cause actual results, performance or achievements to differ materially from those expressed or implied by these forward-looking statements. The forward-looking statements in this presentation are made only as of the date hereof. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of the Company in general, see the Company's periodic filings with the Securities and Exchange Commission (the "SEC"), including its Annual Report on Form 10-K for the year ended December 31, 2019, its Quarterly Report on Form 10-Q for the quarter ended June 30, 2020, and any current and periodic reports filed thereafter. Except as required by law, the Company assumes no obligation and does not intend to update these forward-looking statements or to conform these statements to actual results or to changes in the Company's expectations.

This presentation concerns anticipated products that are under clinical investigation and which have not yet been approved for marketing by the U.S. Food and Drug Administration (FDA). It is currently limited by Federal law to investigational use, and no representation is made as to its safety or effectiveness for the purposes for which it is being investigated.

2

IDEAYA Biosciences Highlights

Leading Synthetic Lethality focused biotechnology company advancing transformative precision medicine therapies for cancer patients

• Breakthrough Science on potential first-in-class Synthetic Lethality programs
• Broad Pipeline of clinical and preclinical precision medicine oncology programs with defined patient biomarkers
• Proven Management Team with deep business and scientific experience has built leading private and public oncology biotech companies
• Pharma Collaborations and Strategic Partnerships with Pfizer and GlaxoSmithKline, including ~$3 billion in potential cash milestones
• Strong Balance Sheet with Capital Efficient Model anticipated to fund operations into 2024 through multiple clinical catalysts over multiple programs
• NASDAQ: IDYA

3

Synthetic Lethality

The Next Frontier in Precision Medicine Oncology

Synthetic Lethality provides a powerful approach to discover the next generation of precision medicine therapies for molecularly-defined patient populations, including MTAP-deletion (~15% of all solid tumors), BRCA/HRD, and high-MSI (16% CRC)

• Synthetic lethality occurs when the simultaneous perturbation of two genes results in cell death
• Synthetic lethal genetic interactions with tumor-specific mutations may be exploited to develop anticancer therapies
• Large-scalescreening for cancer-gene-specific synthetic lethal targets in human cells has progressed through advances in RNA interference and CRISPR-Cas9 editing

Nature Reviews Genetics, Vol. 18, 2017, Hieter, et al

Reference: Charles Boone

4

IDEAYA's Precision Medicine Oncology Pipeline

Building the Leading Synthetic Lethality Biotech

Synthetic Lethality Pipeline

	Indication	Biomarker	Preclinical	IND	Phase 1	Phase 2	Status	Collaboration
IDE397	Solid Tumors	MTAP					Targeting IND Q4 2020	(1)
MAT2A
PARG	Solid Tumors	Novel Biomarker					In vivo Efficacy	(2)
Polθ	Solid Tumors	HRD					In vivo Efficacy	(1)
WRN	Solid Tumors	High-MSI					Cell Activity	(1)
DDT	Solid Tumors	Novel Biomarker					Target Validation

1. Pursuant to GSK Collaboration, Option and License Agreement: MAT2A and WRN: 50/50 US Profits + ex-US Royalties; Polθ: Global Royalties
2. Pursuant to CRUK Evaluation, Option and License Agreement, with ongoing Collaborative Research

DDT = DNA Damage Target, WRN = Werner Helicase, Polθ = DNA Polymerase Theta, HRD = homologous recombination deficiency, MSI = microsatellite instability

Kinase Pipeline

	Indication	Biomarker	Preclinical	IND	Phase 1	Phase 2	Status	Collaboration
	GNAQ/11 Basket	GNAQ/11					Advancing Ph2 Basket (Non-MUM)
IDE196	Monotherapy					Ph2 Expansion in Skin Melanoma
PKC inhibitor	MUM	GNAQ/11					MEK Combo FPI (MUM) June 2020	(3)
	MEK Combo					MEK Combo Enrollment Ongoing (MUM)

1. Pursuant to Pfizer Clinical Trial Collaboration and Supply Agreement PKC = protein kinase C, MUM = metastatic uveal melanoma

5

= Target program milestone through 2020

IDEAYA and GSK Strategic Partnership

Landmark Partnership in Synthetic Lethality

Transformative Strategic Partnership

• Validates IDEAYA Synthetic Lethality platform
• Enhances collective leadership in Synthetic Lethality
• Creates strategic combination opportunities

Key Partnership Terms

• Targets: MAT2A, Pol Theta and Werner Helicase
• Modalities: small molecule inhibitors & protein degraders
• $100M cash upfront
• $20M equity investment as direct private placement
• $50M option exercise fee for MAT2A
• 50/50 US profit share for MAT2A and Werner Helicase
• 20% global development cost share for US profit share
• Potential preclinical, clinical and sales milestones for each licensed product
• Royalties tiered high single-digit to sub-teen double digit %

MAT2A

• IDEAYA leads early clinical; GSK option to exclusive license
• $50M Option Exercise Fee
• 50/50 US Profit Share and ex-US Royalties
• 20% global development cost share
• Cash payments upon clinical and sales milestones

WRN Helicase

• 50/50 US Profit Share and ex-US Royalties
• 20% global development cost share
• Cash payments upon preclinical, clinical and sales milestones

DNA Polymerase Theta

• Milestones and global royalties
• Cash payments upon preclinical, clinical and sales milestones

6	IDEAYA Form 8-K current report filed with the U.S. Securities and Exchange Commission on June 16, 2020

IDEAYA and GSK Strategic Partnership

Partnership Enables Strategic Combinations

Potential Combinations of IDEAYA SL + GSK Programs

Patient

Population

IDE397

MAT2A

Pol Theta

Small Molecule Inhibitor or

Protein Degrader

Werner Helicase

+

+

+

GSK3368715 (Ph 1)	MTAP
Type I PRMT	Deletion
Zejula™	BRCA/HRD
PARP
Dostarlimab (Ph 3)	MSI-H
PD-1

7	IDEAYA Form 8-K current report filed with the U.S. Securities and Exchange Commission on June 16, 2020; GlaxoSmithKline Q2 2020 Earnings Presentation

IDEAYA Synthetic Lethality Platform

Fully-Integrated Target, Biomarker, and Drug Discovery Capabilities

SL Target & Biomarker

Discovery & Validation

Dual CRISPR, CRISPR, siRNA Bioinformatics

Genetically Engineered Models

• Potential 1st-in-class SL targets identified and validated, such as WRN
• SL biomarker discovery has delivered multiple patient population hypotheses
• 3 SL programs advanced to in vivo efficacy in target genetic settings

Drug Discovery

Structure Based Drug Design

Small Molecule Chemistry

Protein Degrader Capabilities

• Crystal structures for all four SL programs obtained to enable SBDD
• Potential best-in-class molecules discovered, including MAT2Ai, IDE397
• Protein degraders advancing for selected targets

Clinical Biomarker

Genomics

Tissue Based (IHC, IF)

Liquid Biopsies

8

IDEAYA Team and Scientific Advisory Board

Scientific Thought Leaders in Synthetic Lethality and Precision Medicine Oncology

IDEAYA Executives & R&D Leadership

Yujiro Hata, M.B.A.	Michael Dillon, Ph.D.	Paul Stone, J.D.	Mark Lackner, Ph.D.
President, Chief Executive Officer, Director	SVP, Chief Scientific Officer		SVP, Chief Financial Officer	SVP, Head of Biology &
	Head of Research			Translational Sciences
Mick O'Quigley, M.B.A.	Paul Barsanti, Ph.D.	Jason Throne, J.D.
VP, Development Operations		VP, Head of Drug Discovery		SVP, General Counsel

IDEAYA Scientific Advisory Board

Alan D'Andrea, M.D.	William Sellers, M.D.	Frank McCormick, Ph.D.	Trey Ideker, Ph.D.
IDEAYA SAB Chair	Broad Institute, Dana Farber, and Harvard, Professor	UCSF, Professor and former Director,	UCSD, Professor, Co-Director Cancer Genomes & Networks
Novartis, Former Head Oncology Research,	Helen Diller Cancer Center	Program, Research in Dual-CRISPR and SL interaction maps
Harvard Medical School, Professor	SL Project Drive initiative	Former President AACR; Founder and CSO, Onyx
Director, Center of DNA Damage and Repair, Dana Farber

Brian Daniels, M.D.	Elizabeth Swisher, M.D.	Jeffrey Hager, Ph.D.
Bristol Myers Squibb, Former SVP Global Development	University of Washington, Professor; Co-Leader, Breast and	Former Chief Technology Officer, IDEAYA
& Medical Affairs	Ovarian Cancer Research Program, Seattle Cancer Care Alliance
	Principal Investigator on multiple PARP inhibitor trials

9

IDEAYA is Advancing the Next Generation of Synthetic Lethality Therapies

Today

PARP

HRD/BRCA

Lynparza (AZ)

Zejula (GSK)

Rubraca (Clovis)

Talzenna (Pfizer)

IDEAYA Synthetic Lethality Pipeline

MAT2A	WRN	Target Discovery
MTAP-Deletion	High-MSI	SL Targets

PARG	Polθ
Replication Stress	HRD
Novel Biomarker

HRD = Homologous Recombination Deficiency, MSI = Microsatellite Instability

10

MAT2A

MAT2A Inhibition is Synthetic Lethal with MTAP Deletion

MTAP Deletion Prevalence ~15% of all Solid Tumors

MTAP-MAT2A Synthetic Lethality Biology

Methionine

MAT2A is key enzyme that

produces SAM in cells

MTAP deletion leads

to MTA accumulationMAT2A MAT2A

inhibitor

		MTA accumulation
		partially inhibits PRMT5	Inhibition of MAT2A
MTA					results in reduction of
MTA			PRMT5	SAM, starving PRMT5
MTA			of its substrate
	Protein Methylation	SAM
	Loss of methylation function of PRMT5
	results in defects in RNA splicing, gene
	expression and genome integrity

MTAP Deletion Prevalence

Cancer Type	N	MTAP Deletions (%)
Glioblastoma	592	41
Mesothelioma	87	32
Esophageal	95	28
Bladder	411	26
Pancreatic	184	22
Melanoma	448	16
Lung Cancer (NSCLC)	1053	15
Head and Neck	523	14
Sarcoma	255	10
Esophagogastric	514	10
Diffuse Glioma	513	9
Breast	1084	3
Ovarian	585	3
Adrenocortical	92	3
Thymic	123	3
Hepatocellular	369	3
Renal non-clear cell	348	2

Data from The Cancer Genome Atlas in cBioPortal

11

IDEAYA MAT2A Inhibitors Demonstrate Synthetic Lethality in MTAP-/- Cell Lines & PD Modulation of SAM Levels

Structurally Enabled Lead Optimization

Synthetic Lethality in HCT116 Cell Line

• IDB proprietary MAT2Ai co-crystal structure (1.33Å)
• +17 high-resolutionco-crystal structures

Fold change (DMSO)

1.5

1.0

0.5

0.0

IDB361

HCT116 Parental HCT116 MTAP-/-

• Lead series includes multiple compounds with nM potency and >5x IC50 ratio in HCT116 wt vs MTAP -/-

IDEAYA Data

-3-2-1 0 1 2

Concentration (µM)	IDEAYA Data

Consistent sensitivity across multiple MTAP-/- cell lines

IDEAYA Data

IC50 (uM)

20

15

10

5

4

3

2

1.0

0.8

0.6

0.4

0.2

0.0

KP4	RT112/84	SW780	H647	BXPC3		MTAPnull	HCT116	WT
				HCT116

PD Modulation:

SAM Levels in

HCT116 Cell Line

IDEAYA Data

12

IDE397: MAT2A Development Candidate Nominated

Targeting IND in Q4 2020

In Vivo Efficacy in HCT 116 MTAP-/- Model

•	IDE397		600	Vehicle		HCT-116MTAP-/-
	(5 mg/kg)			IDE397 5mg/kg QD
	demonstrates	S.E.M.	500
	greater tumor	400
	growth	3
		)±
	inhibition at	(mm
	1/60th the dose	Volume	300
	vs AGI-25696
•	Published AG-	Tumor	200
	270 preclinical	Mean
	dose is typically	100
	200 mg/kg QD
			0
			0	3	6	9	12	15
			First dose Day 1		Study Day
IDEAYA Data

				Tumor Pharmacodynamic Effect
	20			• Significant reduction in tumor SAM
	HCT-116MTAP-/-		levels with IDE397 at 5 mg/kg
	IDE397	AGI-25696
	0				Tumor SAM HCT-116MTAP-/-
	5	100	300
(%)	S.E.M.	5000
mpk	mpk	mpk
	-20				4000
growthTumorinhibition				SAMTumor(ng/g)
			1000
					3000
	-40
					2000
	-60			Mean
				0
	-80				Vehicle	IDE397 5 mg/kg
	-100			IDEAYA Data

13

IDE397: MAT2A Development Candidate Nominated

Differentiated Profile vs Agios Compounds

Efficacy in Endogenous MTAP-/- Model (KP4)

1,500 Vehicle

IDE397 10 mg/kg QD

)± S.E.M.	1,200
3
(mmVolume	900
Mean Tumor	600
300
			First dose
	0				Day 1

0

3

6

9

12

15

Study Day

IDB397 demonstrates efficacy at 1/30th of the dose of Agios MAT2A compound (see data)

IDEAYA Data

	1,500
	1,250
mm3)	1,000
Volume	750				79% TGI
Tumor
				P = 2e-31
Average
500
	250
				+/- S.E.M.
	0
	15	20	25	30	35
			Days post implant
		Vehicle		MAT2Ai III 300 mg/kg

Keystone Symposium 2017

Agios Data

IDE397 vs Agios Compounds

IDE397 demonstrates greater in vivo efficacy at 5 to 10mg/kg

• More potent vs. AGI-25696 at 1/30th to 1/60th the dose in MTAP-deletion models

IDE397 has not caused liver injury or increased unconjugated bilirubin

• Liver injury not observed in tox studies
• Not an inhibitor of UGT1A1

IDE397 has favorable physical properties, including solubility

• AG-270observed non-linear exposure >200mg QD (GI absorption)

IND-enabling studies initiated and targeting Q4 2020 IND

14

IDE397 Demonstrates Monotherapy Tumor Regression in an MTAP-Deleted Endogenous NSCLC Model

IDE397 produced dose-dependent efficacy in a NSCLC model with regression (TGI >100%) at 30 mg/kg

In Vivo Endogenous NSCLC MTAP (-/-) PDX Model

Volume		2000
S.E.M.	1500
MeanTumor	±	1000
)
3
(mm	500
		0
		7	14	21	28

Days Post Inoculation

Vehicle control

3 mg/kg IDE397

10 mg/kg IDE397

30 mg/kg IDE397

IDEAYA Data

15

PARG

PARG Synthetic Lethality Program

Candidate Biomarkers: Replication Stress/HRD/Novel Biomarker

PARG Biology

Poly(ADP-ribose) glycohydrolase (PARG) regulates DNA repair mechanisms

PARG hydrolyzes PAR chains in final step of DNA Damage Repair (DDR) cycle

Cancer Research

August 2019

Dysfunction of Poly(ADP-ribose) Glycohydrolase Induces a Synthetic Lethality Effect in Dual Specificity Phosphatase 22-deficient Lung Cancer Cells

PARG & DNA Replication Vulnerabilities

March 2019

DNA Replication Vulnerabilities

Render Ovarian Cancer Cells

Sensitive to Poly(ADP-ribose)

Glycohydrolase Inhibitors

PARGi demonstrate cell viability effects in ovarian cell lines resistant to PARPi

Sasaki et al., Cancer Res, Aug 2019, 79:3851-3861; Jain et al, Cancer Res Jul 2019;79:4491-4502; Pillay et al., Cancer Cell Mar 2019, 35, 519-533

16

PARG Synthetic Lethality Program

Drug Discovery on Potential 1st in Class DDR Synthetic Lethality Target

PARG Drug Discovery Program

PARG Inhibitor In Vivo PD and Efficacy Data

IDEAYA has discovered potent PARG inhibitors SAR guided by structure-based drug design

Significant tumor PAR accumulation observed in vivo

(ng/ml) ± S.E.M.	100000					IDB-PARG plasma		10000
					concentration
10000					Tumor PAR accumulation	8000	PAR/mg pg
protein adjusted viability IC50
1000							6000
Plasma concentration	100							4000	.M.E.S ± protein
10							2000
	1							0
	0	4	8	12	16	20	24

1st dose - 0 hrs	Time post dose (h)
2nd dose - 8 hrs

• Extensive research in PARG biology and chemistry
• Multiple collaborations ongoing to refine patient selection biomarker strategy

IDB-PARG Potency

Biochemical IC50	7 nM
PAR Foci cell EC50	50 nM
Cell Viability EC50	510 nM

IDEAYA PARG inhibitors demonstrate in vivo TGI in a model with a replication stress gene signature

		2500			Vehicle control
Volume				IDB-PARG
S.E.M.	2000
1500
Mean Tumor	) ±				TGI = 47%
3	1000
(mm
500
		0
		7	14	21	28

IDEAYA Data

IDEAYA Data

Days post inoculation

17

PARG Synthetic Lethality Program

IDB-PARG Demonstrates In Vivo Tumor Regression in PDX Model

Robust Monotherapy Activity Observed in Multiple PDX Models

• IDEAYA-proprietaryNovel Synthetic Lethality Biomarker
• Targeting PARG development candidate in 2021

			PDX-1
	1000
		Vehicle
S.E.M.)±		IDB-PARG				±S.E.M.)
750
3						3
(mm						(mm
VolumeTumor	500					VolumeTumor
Mean	250					Mean
	0
	0	7	14	21	28	35
		1st dose Day 1	Study Day

PDX-2

1000

Vehicle

IDB-PARG

750

500

250

0

0	7	14	21	28	35
	1st dose Day 1	Study Day

IDEAYA Data

18

WRN

Werner Helicase Synthetic Lethality Program

Candidate Biomarker: High-MSI (15% GI Cancers and 16% CRC)

Werner Helicase Biomarker

Werner Syndrome Helicase is Required for the Survival of Cancer Cells with Microsatellite Instability

IDEAYA Publication

Cell Press, iScience, March 2019, Hager et al

Werner Helicase Drug Discovery

• Discovery: multiple hit discovery campaigns using a range of screening formats and compound libraries completed
• Screening: robust suite of biochemical and biophysical assays to identify WRN inhibitors and differentiate false positives
• Structurally Enabled: structure of WRN helicase domain solved
• Lead Series: identified a lead series with <10 nM IC50 potency in a Werner helicase biochemical assay
• >10,000x potency improvement obtained through ongoing SAR

Project Drive: Werner is essential in MSI-high cancer cell lines

Project Drive

IDB-WRN1

ATPase IC50 = ~30 ∝M

IDB-WRN2

ATPase IC50< 10 nM

IDEAYA Data

	IDB-WRN1
120	IDB-WRN2

Inhibition	60				>10,000x
	100
Percent	80
40
	20
	0
	.00001	.0001	.001	.01	.1	1	10	100	1000
	0
	0
	0
	0
	0

Compound (uM)

19

Werner Helicase Synthetic Lethality Program

Candidate Biomarker: High-MSI (15% GI Cancers and 16% CRC)

WRN Inhibitor Cellular PD and Viability

• PD-marker:dose dependent increase of DNA damage marker γH2AX demonstrated at 48 hours
• Cell viability: MSI-highspecific cell viability effect observed across multiple cell lines; no effect in MSS cell lines
• Target Milestone: In

vivo efficacy data in 2020

WRN Inhibitors Phenocopy Genetic Knockdown

WRN siRNA

WRN inhibitor

IDEAYA Data

IDEAYA Data

20

Polθ Synthetic Lethality Program

Candidate Biomarker: BRCA/HRD

Polθ Inhibitor Cell Viability

Polθ Inhibitor In Vivo Activity

PolQ

Percent of DMSO treated control

100

50

0
0.001	0.01	0.1	1	10	100

DLD1 DLD1(-/-BRCA2)

Combination of Polθi and niraparib demonstrates tumor regression in DLD1 BRCA2-/- xenograft model

• Combination of Polθi with niraparib greatly enhances activity of niraparib in DLD1 BRCA2-/- xenograft model

1250

) ±S.E.M.	1000
3
(mm	750

Vehicle

IDBPOLQ 100 mg/kg QD Niraparib 45 mg/kg QD

IDBPOLQ 100mg/kg QD + Niraparib 45 mg/kg QD

Polθ-1 (∝M)

IDEAYA Polθ ATPase inhibitors show cell viability effects in DLD1 BRCA2-/- cell lines

• Regressions observed for all animals dosed with combination in the study
• All treatments well-tolerated, with body weights similar to control at end of study

Volume	500
Tumor
Mean	250

0

7

14

21

28

1st dose on Day 1

Study Day

IDEAYA Data

IDEAYA Data

21

IDE196

IDE196 Phase 1/2 Clinical Program Summary

PKC Inhibitor Targeting GNAQ/GNA11 Hotspot Mutation Tumors

Metastatic Uveal Melanoma (MUM)

IDE196 + MEK Combo

MUM Indication: Focus on Clinical Combinations IDE196 + MEK Combo FPI (June 2020)

Pfizer Clinical Trial Collaboration and Supply Agreement IDE196 + MEKi (binimetinib) Preclinical Synergy

GNAQ/GNA11 Basket Trial (Non-MUM)

IDE196 Monotherapy

GNAQ/11 Basket (Non-MUM): Evaluating Monotherapy Ph2 Expansion in Skin Melanoma (July 2020)

In 4 evaluable Skin Melanoma patients observed 100% DCR and 1 confirmed PR by RECIST Guidelines (version 1.1)

• IDE196 + MEK inhibitor Combo: MUM Indication
• • Study goals are to identify tolerated combo dose and enhance clinical activity in MUM
  • • AACR 20191: IDE196 BID Monotherapy in MUM (30 pts), ~73% Disease Control Rate & ~13% ORR
    • AACR 20202: IDE196 + MEK preclinical synergy demonstrated in uveal melanoma
  • Interim data anticipated late 2021 to early 2022
• IDE196 Monotherapy: GNAQ/GNA11 Basket Trial (Non-MUM)
• • Phase 2 expansion in Skin Melanoma with 100% DCR and 1 confirmed PR (by RECIST 1.1) in first 4 evaluable patients
  • Interim data anticipated H1 2021

1 Novartis Data 2 IDEAYA Data

22

IDE196 Monotherapy Confirmed PR by RECIST Guidelines (version 1.1) in Metastatic Skin Melanoma Patient with GNAQ Q209L Hotspot Mutation

Clinical Background

• Nivo, ipi, and pembro treatment through 2016 and 2017; progressed with liver metastases in 2018
• Restarted nivo in combination with radiation to liver lesions in 2018, and then T-VEC to cutaneous lesions in 2019
• Subsequent progression followed by adoptive T-cell therapy (TIL) May 2019; confirmed progression noted Feb 2020
• Started on IDE196 400mg BID Feb 2020
• PR (-31.1%) at 8 weeks, sustained at 20 weeks (-37%) with reduction in target liver lesion and inguinal lymph node
• Ongoing treatment with IDE196

CT Scan at Baseline and 20 Weeks

Baseline

20 weeks

23IDEAYA Data as of 8/1/2020

IDE196 Potential Addressable Market

Solid Tumors Having GNAQ/11 Hotspot Mutations

GNAQ/11 Hotspot Patients in US & EU5

Rare Oncology Indication Comps

7

(Patients in 1,000's)

6

52.5

4

3

23.5

1

0

IDE196 GNAQ/GNA11 Hotspot Population

MUM		GNAQ/11 Other Solid Tumors (Hotspot)

US and EU5

~3.5 K GNAQ/11 Metastatic Uveal Melanoma (MUM) ~2.5 K GNAQ/11 Other Solid Tumors (Hotspot)

(Patients)

7000

6000

5000

4000

3000

2000

1000

0

	GNAQ/11: The Cancer Genome Atlas (TCGA), IDEAYA Analysis
	ROS1 Advanced NSCLC: Turning Point Therapeutics 11/2019 corporate presentation, prevalence estimates (160,000 US + 117,000 EU5) x 2% mutation rate
	HRASm HNSCC estimates: KURA Oncology 11/2019 corporate presentation (2,900-4,700 patients US)
	FGFR2 rearrangements in cholangiocarcinoma: Incyte 6/2019 press release (~2,000-3,000 patients US/EU/JPN)
24	TRK fusion: LOXO 11/2018 corporate presentation Ex 99.2 (2,500-3,000 patients US)
4L GIST estimates: Deciphera 11/2019 corporate presentation (~2,100 patients US)

IDEAYA's Precision Medicine Oncology Pipeline

Target Milestones Through 2021

Synthetic Lethality Pipeline

	Indication	Biomarker	Preclinical	IND	Phase 1	Phase 2	Target Milestones Through 2021	Collaboration
IDE397	Solid Tumors	MTAP					IND Q4 20	(1)
MAT2A					Phase 1 Initiation H1 2021
PARG	Solid Tumors	Novel Biomarker					Development Candidate 2021	(2)
Polθ	Solid Tumors	HRD					IND 2021	(1)
WRN	Solid Tumors	High-MSI					In vivo Efficacy 2020	(1)
DDT	Solid Tumors	Novel Biomarker					Chemistry Optimization

1. Pursuant to GSK Collaboration, Option and License Agreement: MAT2A and WRN: 50/50 US Profits + ex-US Royalties; Polθ: Global Royalties
2. Pursuant to CRUK Evaluation, Option and License Agreement, with ongoing Collaborative Research

DDT = DNA Damage Target, WRN = Werner Helicase, Polθ = DNA Polymerase Theta, HRD = homologous recombination deficiency, MSI = microsatellite instability

Kinase Pipeline

	Indication	Biomarker	Preclinical	IND	Phase 1	Phase 2	Target Milestones Through 2021	Collaboration
	GNAQ/11 Basket	GNAQ/11							Phase 2 Basket (Non-MUM) Enrolling
IDE196	Monotherapy							Interim Data H1 2021
PKC inhibitor	MUM	GNAQ/11							MEK Combo Phase 2 Expansion	(3)
	MEK Combo							Interim Data Late 2021 to Early 2022

1. Pursuant to Pfizer Clinical Trial Collaboration and Supply Agreement PKC = protein kinase C, MUM = metastatic uveal melanoma

25

= Target program milestone through 2021