Erasca : Corporate Presentation January 2023

On a Journey to Erase Cancer

Erasca Corporate Presentation

January 2023

Disclaimer: Forward Looking Statements & Market Data

We caution you that this presentation contains forward-looking statements. All statements other than statements of historical facts contained in this presentation, including statements regarding our future results of operations and financial position, business strategy, research and development plans, the anticipated timing, costs, design and conduct of our ongoing and planned preclinical studies and clinical trials for our product candidates, the potential benefits from our current or future arrangements with third parties, the timing and likelihood of success of our plans and objectives, and future results of anticipated product development efforts, are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "target," "project," "contemplates," "believes," "estimates," "predicts," "potential" or "continue" or the negative of these terms or other similar expressions. The inclusion of forward-looking statements should not be regarded as a representation by us that any of our plans will be achieved. Actual results may differ from those set forth in this presentation due to the risks and uncertainties inherent in our business, including, without limitation: our approach to the discovery and development of product candidates based on our singular focus on shutting down the RAS/MAPK pathway, a novel and unproven approach; we are early in our development efforts and have only five product candidates in clinical development and all of our other development efforts are in the preclinical or development stage; the retrospective analysis of pooled clinical data for ERAS-007 and ERAS-601 covers multiple clinical trials with different designs, inclusion criteria, and dosing regimens, which cannot be directly compared, and therefore may not be a reliable indicator of efficacy and safety data; interim results of clinical trials are not necessarily indicative of final results and one or more of the clinical outcomes may materially change as patient enrollment continues, following more comprehensive reviews of the data and more patient data become available; potential delays in the commencement, enrollment, and completion of clinical trials and preclinical studies; our dependence on third parties in connection with manufacturing, research, and preclinical and clinical testing; unexpected adverse side effects or inadequate efficacy of our product candidates that may limit their development, regulatory approval, and/or commercialization, or may result in recalls or product liability claims; unfavorable results from preclinical studies or clinical trials; results from preclinical studies or early clinical trials not necessarily being predictive of future results; the inability to realize any benefits from our current licenses and acquisitions and any future licenses, acquisitions, or collaborations, and our ability to fulfill our obligations under such arrangements; regulatory developments in the United States and foreign countries; our ability to obtain and maintain intellectual property protection for our product candidates; our ability to fund our operating plans with our current cash, cash equivalents, and investments; our ability to maintain undisrupted business operations due to the COVID-19 pandemic, including delaying or disrupting our clinical trials, manufacturing, and supply chain; unstable market and economic conditions having serious adverse consequences on our business, financial condition and stock price; and other risks described in our prior filings with the Securities and Exchange Commission (SEC), including under the heading "Risk Factors" in our annual report on Form 10-K for the year ended December 31, 2021, and any subsequent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and we undertake no obligation to update such statements to reflect events that occur or circumstances that exist after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions, and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and by us.

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Strong financial position with high quality investor base and industry visibility

Our name is our mission: to erase cancer

Vision to one day erase cancer1 in at least 100,000 patients annually as a leading global oncology company

Experienced leadership team and SAB with track record of serial successes

• Founded by Jonathan Lim, MD & Kevan Shokat, PhD around disruptive idea to target RAS

• World class scientific advisory board of leading pioneers in RAS/MAPK pathway

• Team with deep experience in efficient planning and execution of global clinical trials

CNS = central nervous system

Industry leading portfolio focused on shutting down the RAS/MAPK pathway

• Naporafenib pan-RAFi with first-in-class potential for NRASm & other MAPK tumors

• ERAS-007ERKi & ERAS-601SHP2i with best-in-class potential for MAPK tumors

• ERAS-801, CNS-penetrantEGFRi with first-in-class potential for EGFR-driven rGBM

• ERAS-3490, CNS-penetrantKRAS G12Ci with best-in-class potential in NSCLC

• ~$365M in cash, cash equivalents, and short-term marketable securities2; plus $100M equity financing announced on 12/9/2022

• One of Fierce Biotech's 2021 "Fierce 15" most promising biotechnology companies

• Number of patients alive and free of cancer or free from cancer progression 2-yrs after starting an Erasca regimen, as measured by disease-free survival (adjuvant setting) and progression-free survival (metastatic setting)
  2 Unaudited, as of September 30, 2022

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SAB includes world's leading experts in the RAS/MAPK pathway

World expert in SHP2 who helped pioneer development of the first SHP2 inhibitor with Novartis

Stephen Blacklow

MD, PhD

Erasca co-founder.World expert in RAS

who pioneered development of approaches to inhibit KRAS G12C (RAS-GDP) and active states of RAS (RAS-GTP)

Kevan Shokat,

PhD

World expert in ERK, having studied nearly every ERK inhibitor that has been or is being developed, as well as targeted therapies directed against KRAS, BRAF, and MEK mutations

Ryan Corcoran,

MD, PhD

Pablo Rodriguez-

Viciana, PhD

World expert in RAS/MAPK pathway with focus on the SHOC2 phosphatase complex as a unique regulatory node required for efficient pathway activation in the context of diseases such as cancer and RASopathies

World expert in RAS/MAPK pathway signaling and identifying novel combination therapies to shut it down

Karen

Cichowski, PhD

World expert in targeted oncology therapies who pioneered the development of Gleevec®, which helped launched the precision oncology revolution

George

Demetri, MD

World expert in structure-based drug design; former head of research at Agouron and former head of Genentech's Research and Early Development (gRED)

Michael

Varney, PhD

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~5.5m lives at stake annually worldwide with RAS/MAPK pathway alterations; 70+% of unmet needs are "blue oceans" with no approved targeted therapies

New cases estimated worldwide per annum (thousands; numbers may not add up due to rounding)

Alterations	GBM	HNSCC	NSCLC	CRC	Melanoma	PDAC	Other solid	AML	US	EU	ROW	Global
tumors
EGFR*/FLT3	125	513	184	338	-	-	-		61	82	222	917	1,220
NF1	25	58	98	34	33	1.9	434		3.2	75	159	453	687
KRAS G12C	-	2.8	240	57	-	5.1	45		0.1	36	82	232	350
KRAS G12D	0.2	4.7	68	238	0.5	178	201		1.3	65	171	456	692
RAS Q61X	0.4	23	35	80	69	32	155		4.1	51	106	242	399
RAS G13R	-	9.4	5.9	5.5	2.1	-	14		0.5	3.6	8.1	26	37
Other RAS	0.6	31	162	452	4.4	211	331		13	112	291	800	1,203
BRAF V600E/K	2.0	1.9	23	180	93	1.4	158		0.4	63	127	271	461
BRAF Class 2	0.4	3.8	18	6.9	5.3	0.5	57		-	11	23	58	92
BRAF Class 3	0.1	0.9	12	17	2.5	-	29		0.2	6.1	15	40	61
Other BRAF	-	-	3.9	-	1.9	0.3	0.5		-	0.7	1.0	4.9	6.6
MEK	0.2	1.9	12	8.8	4.6	0.2	22		-	5.2	11	33	50
Co-occurring activating MAPK	1.4	10	62	59	37	7.1	84		3.0	33	69	162	264
pathway alterations**
US	12	29	93	114	77	51	153		11	542
EU	34	76	194	398	116	124	324		18		1,285
Rest of World	109	555	635	964	60	264	1,053		57			3,696
Global	155	660	923	1,476	253	438	1,530		86				5,522
			Blue ocean opportunities	Red ocean opportunities

• Post-Osimertinibresistant population shown for EGFRm NSCLC except for SCLC transformation ** Co-occurring activating MAPK pathway alterations exclude EGFR overexpression
  Source: SEER database (2020), ECIS database (2020), GLOBOCAN database (2020), The AACR Project GENIE Consortium version 8.1 (2020), TCGA Research Network: https://www.cancer.gov/tcga, Tyner JW et al.
  (2018) PMID: 30333627, Brenner CW et al (2013) PMID: 24120142, Chen J et al. (2020) PMID: 32015526, and Ostrom QT, et al. (2020) PMID: 33123732

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