Prelude Therapeutics Incorporated : August 2023 Corporate Deck

Corporate Presentation

August 2023

Forward Looking Statements

This presentation contains "forward-looking" statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to: our plans to develop and commercialize small molecule therapies, our expectations about timing and ability to commence, enroll or complete clinical studies, present data and clinical results or updates, and to obtain regulatory approvals for PRT1419, PRT2527, PRT3645, PRT3789, our oral SMARCA2 candidate and other candidates in development, the ability of our product candidates to treat various cancers, the ability to discover additional suitable candidates for regulatory approval and the sufficiency of our cash and cash equivalents to fund our operations.

Any statements contained herein or provided orally that are not statements of historical fact may be deemed to be forward-looking statements. In some cases, you can identify forward- looking statements by such terminology as ''believe,'' ''may,'' ''will,'' ''potentially,'' ''estimate,'' ''continue,'' ''anticipate,'' ''intend,'' ''could,'' ''would,'' ''project,'' ''plan,'' ''expect'' and similar expressions that convey uncertainty of future events or outcomes, although not all forward-looking statements contain these words. Statements, including forward-looking statements, speak only to the date they are provided (unless an earlier date is indicated).

Certain data in this presentation are based on cross-study comparisons and are not based on any head-to-head clinical trials. Cross-study comparisons are inherently limited and may suggest misleading similarities or differences. This presentation shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or other jurisdiction.

These forward-looking statements are based on the beliefs of our management as well as assumptions made by and information currently available to us. Although we believe the expectations reflected in such forward-looking statements are reasonable, we can give no assurance that such expectations will prove to be correct. If such assumptions do not fully materialize or prove incorrect, the events or circumstances referred to in the forward-looking statements may not occur. We undertake no obligation to update publicly any forward- looking statements for any reason after the date of this presentation to conform these statements to actual results or to changes in our expectations, except as required by law. Accordingly, readers are cautioned not to place undue reliance on these forward-looking statements. Additional risks and uncertainties that could affect our business are included under the caption "Risk Factors" in our filings with the Securities and Exchange Commission, including our Annual Report on Form 10-K for the year ended December 31, 2022.

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Prelude Therapeutics: Aiming to Deliver Precision Medicines to Patients with Cancer

Powerful R&D Engine

Diversified Pipeline		Large Commercial
	Opportunities

Exceptional Team		Well Capitalized

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Prelude Discovery and Development Engine

R&D ENGINE

Internal

Discovery

Engine

Clinical

Development

Expertise

APPROACH

Target

Mechanisms that drive

meaningful benefit in patients

with cancer

Discover

Optimized molecules that overcome the limitations of current treatments

Translate

Science into meaningful treatments for patients

DIFFERENTIATED

PROGRAMS

CDK9MCL1

SMARCA2 CDK4/6

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Differentiated Programs with Transformative Potential for Patients with Cancer

Potentially Best-in-	Optimized PK
Class Selectivity	Profile
Potential to avoid off-target	Potential for maximal
toxicity and higher clinical	target engagement and
activity	improved cardiac safety
CDK9	MCL1

SMARCA2	CDK4/6
Potent and Selective	Highly Selective
CDK4 Bias
Degrader
Potential for high tissue and
Potential to address major
brain penetration and better
unmet need in biomarker-
combinability
selected patients

Powerful Discovery Engine expected to generate new INDs every 12-18 months

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