Prelude Therapeutics Incorporated : January 2022 Corporate Presentation

Precision Oncology

Redefined

Corporate Presentation January 2022

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 and to obtain regulatory approvals for PRT543, PRT811, PRT1419, PRT2527 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, the potential impact of the COVID-19 pandemic 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).

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 Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission for the three months ended September 30, 2021.

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Prelude Therapeutics: Vision

Build a fully integrated oncology company

on the foundation of drug discovery excellence to deliver novel precision oncology medicines to patients with underserved cancers

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Prelude Therapeutics: Building for Success

Internal Discovery Engine

Powered by experienced drug developers with a proven track record of multiple successful oncology medicines

Differentiated R&D Approach

Effective integration between cancer biology and medicinal chemistry to rapidly iterate and discover optimized molecules in a target class agnostic fashion

Strong Execution and Commitment to Discovery

4 INDs approved in 4 years; 4 differentiated clinical candidates currently advancing through Phase 1 and into Phase 2/3 clinical development; 2 new additional INDs expected in 2022

Focused Clinical Development in Underserved Cancers

Clinical trial designs in selected cancer patients allowing efficient 'go / no go' decisions in caner types with potential for rapid regulatory approval

Strong Financial Position: ~$320M Cash & Marketable Securities (9/30/21)

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Building a Deep Portfolio of Oncology Assets

Target	PRMT5
MOA	mRNA Splicing &
DNA Repair
Molecule(s)	PRT543 & PRT811
Development	Phase 1
Stage	Expansion
Target	Spliceosome Mutations
Cancers	Selected CNS
	HRD+

MCL1

Apoptosis

PRT1419

Phase 1

Escalation

Venetoclax and TKI-

Resistant Heme and

Solid

CDK9

Transcriptional

Regulation

PRT2527

Phase 1

Escalation

MYC-driven Heme and

Solid

SMARCA2

(BRM)

Synthetic Lethality

PRT-SCA2

IND Target

2022

SMARCA4 (BRG1)

Deleted NSCLC and

Others

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