Graphite Bio : Corporate Presentation June 2022

Realizing the full promise of gene editing to transform lives

Corporate Presentation

June 2022

Forward looking statements

Statements in this Presentation that are not statements of historical fact are forward-looking statements. Such forward-looking statements include, without limitation, statements regarding our research and clinical development plans, the clinical and therapeutic potential of our product candidates and platform technology, our expected manufacturing capabilities, strategy, regulatory matters, market size and opportunity, future financial position, forecasted expenses and cash runway, prospects, plans, objectives, and our ability to achieve certain milestones, and the timing thereof. Words such as "believe," "anticipate," "plan," "expect," "intend," "will," "may," "goal," "potential" and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements necessarily contain these identifying words. These forward-looking statements are based on the beliefs of the management team at Graphite Bio, Inc. ("Graphite Bio") as well as assumptions made by and information currently available to us. Such statements reflect the current views of Graphite Bio with respect to future events and are subject to known and unknown risks, including business, regulatory, economic and competitive risks, uncertainties, contingencies and assumptions about Graphite Bio, including, without limitation, risks inherent in developing therapeutic products, future results from our ongoing and planned clinical trials and preclinical research, our ability to obtain adequate financing to fund our planned clinical trials and other expenses, trends in the industry and competitive landscape, the legal and regulatory framework for our industry, our future expenditures and overall market conditions. In light of these risks and uncertainties, the events or circumstances referred to in the forward-looking statements may not occur. The actual results may vary from the anticipated results and the variations may be material. These forward-looking statements should not be taken as forecasts or promises nor should they be taken as implying any indication, assurance or guarantee that the assumptions on which such forward-looking statements have been made are correct or exhaustive or, in the case of the assumptions, fully stated in this presentation. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date this presentation is given. This presentation discusses product candidates that are or will be under clinical investigation and which have not yet been approved for marketing by the U.S. Food and Drug Administration (the "FDA"). No representation is made as to the safety or effectiveness of these product candidates for the therapeutic use for which such product candidates are being or will be studied.

This presentation contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other industry data. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. Graphite Bio has not independently verified the data generated by independent parties and cannot guarantee their accuracy or completeness.

This presentation shall not constitute an offer to sell or the solicitation of an offer to buy any securities.

Graphite Bio, Inc.

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Graphite Bio: Realizing the full promise of gene editing

Powerful Next-Generation

UltraHDR™ Gene Editing Platform

• Harnessing the power of high- efficiency homology directed repair to fulfill the original goal of CRISPR gene editing
• "Find & replace" genes anywhere in the genome - correct, replace, insert
• Preclinical validation across a wide range of cell types and diseases

Robust Pipeline of

Potential One-Time Cures

• Initial focus on HSC-based cures for serious and life-threatening diseases
• First-in-industryapproach to directly correct the sickle cell mutation
• R&D programs designed to validate broad platform capabilities

Poised to Deliver

for Patients

• Founded by Stanford University genetic medicine pioneers
• Experienced management team and board with track record of developing innovative therapies
• $352.1 million in cash, cash equivalents and investments in marketable securities (as of 3/31/2022);
  cash runway into 4Q 2024

Graphite Bio, Inc.

HSC, hematopoietic stem cell; R&D, research and development.

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Harnessing the power of homology directed repair to unleash the full potential of CRISPR gene editing

Cutting is easy		Precision repair is hard
CRISPR Nuclease		2nd gen CRISPR Nuclease

Non-homologous end joining	Homology directed repair
(Default error-prone repair)	(Precision repair)
**	Donor DNA template
Method to	Method to
break and disrupt	find and replace

Homology directed repair

• The original goal of gene editing and CRISPR technology
• The most precise DNA editing system in nature
• Takes CRISPR beyond cutting and knock-outs - able to fix genetic lesions anywhere
  in the genome
• Has been historically difficult to achieve at high efficiencies until now

Graphite Bio, Inc.

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Our UltraHDR™ Platform: Building on CRISPR technology to 'find & replace' any gene

FIND:		REPLACE:		OPTIMIZE:
Proprietary HiFi Cas9 RNP / modified guide		AAV6 delivers donor DNA template		Stem cells prepared
RNA finds gene and precisely cuts		to drive high-efficiency HDR		and optimized for HDR

R691A

sgRNA

ITR				ITR
			Homologous DNA
			donor template

• Retains high activity
• Reduced off-target edits by 30- to 100-fold
• Minimized cellular response

• Non-integrating
• Up to 4kb template
• Enables high-efficiency HDR
• One lot may treat 1000s of patients

• HSC biology expertise and culture optimization
• Unprecedented editing efficiencies as high as 70%
• Successful GMP manufacturing

Graphite Bio, Inc.

GMP, good manufacturing practices; HDR, homology directed repair; HiFi Cas9, high-fidelity Cas9; HSC, hematopoietic stem cell; RNP, ribonucleoprotein.

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