Repare Therapeutics : Corporate Presentation September 2022

A Leader in Precision Oncology

Corporate Presentation

September 2022

Disclaimer

Statements contained in this presentation regarding matters that are not historical facts are "forward‐looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Words such as "anticipates," "believes," "expects," "intends," "plans," "potential," "projects," "would" and "future" or similar expressions are intended to identify forward‐looking statements. Each of these forward‐looking statements involves substantial risks and uncertainties that could cause actual results to differ significantly from those expressed or implied by such forward‐looking statements. Forward‐looking statements contained in this presentation include, but are not limited to, statements regarding the initiation, timing, progress and results of our current and future preclinical studies and clinical trials, including specifically our clinical trials of RP‐3500 and RP‐6306; the expected timing of program updates and data disclosures; the timing of filing INDs and other regulatory documents, including the initiation of IND‐enabling studies for RP‐2119; the timing and likelihood of seeking regulatory approval for our product candidates; the competitive landscape for our product candidates; our ability to identify and develop additional product candidates using our SNIPRx platform; and our estimates regarding expenses, future revenue, capital requirements, cash runway and needs for additional financing.

These forward‐looking statements reflect our current beliefs and expectations. Many factors may cause differences between current expectations and actual results, including the duration and impact of the ongoing COVID‐19 pandemic on our business and market volatility, unexpected safety or efficacy data observed during preclinical or clinical studies, clinical site activation rates or clinical trial enrollment rates that are

lower	than expected, changes	in expected or	existing competition,	changes
in the	regulatory environment,	and unexpected	litigation or other	disputes.

These and other risks are described more fully in our filings with the Securities and Exchange Commission ("SEC"), including the "Risk Factors" section of our Quarterly Report on Form 10‐Q filed with the SEC on August 4, 2022, and other documents we subsequently filed with or furnished to the SEC. All forward‐looking statements contained in this presentation speak only as of the date on which they were made. Except as required by law, we assume no obligation to update any forward‐ looking statements contained herein to reflect any change in expectations, even as new information becomes available.

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 limitations, and you are cautioned not to give undue weight to such estimates. Neither we nor any other person makes any representation as to the accuracy or completeness of such data or undertakes any obligation to update such data after the date of this presentation. 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.

Solely for convenience, the trademarks and trade names in this presentation may be referred to without the ® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert their rights thereto.

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Leading clinical‐stage precision oncology company focused on synthetic lethality

RP‐6306, a first‐in‐class, oral PKMYT1 inhibitor, drives genomic instability in CCNE1‐amplified tumors

RP‐6306 with Ph 1 monotherapy and multiple combination trials ongoing

Camonsertib (RP‐3500),

1. potential best‐in‐class ATR inhibitor with durable responses and clinical

RP‐3500 benefit in Ph 1/2 and strategic validation through Roche partnership

Robust pipeline

of SL‐based therapeutic opportunities, including RP‐2119 and a pipeline of advanced preclinical opportunities

Proprietary genome‐wide

CRISPR‐enabled SNIPRx platform, focused on genomic instability and DNA damage repair, enabling novel target identification and differentiated patient selection insights

Current Balance Sheet funds Repare through multiple value‐creating milestones into 2026

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Experienced team proven in drug discovery and development

Management team
Lloyd M. Segal	Steve Forte, CPA
President & CEO	EVP, Chief Financial Officer

Michael Zinda, PhD	Kim A. Seth, PhD
EVP, Chief Scientific Officer	EVP, Chief Business Officer

Maria Koehler, MD, PhD	Cameron Black, Ph.D.
EVP, Chief Medical Officer	EVP, Head of Discovery

Philip Herman

EVP, Head of Commercial

& New Product Development

Scientific founders

Daniel Durocher, PhD

Developed CRISPR SL platform Deep DNA repair knowledge

Lunenfeld‐Tanenbaum Research Institute (LTRI) & professor at University of Toronto

Agnel Sfeir, PhD

DDR and cancer pathway investigator Pioneer in Polθ, genome instability Professor, MSKCC

Frank Sicheri, PhD

Globally recognized structural biologist, expert in eukaryotic cell signaling, drug mechanism of action

LTRI & professor at University of Toronto

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Focused on precision oncology for untapped cancer lesions

Focused on 71% untapped

target space	Focus of precision oncology for 20 years:
(% of tumors)	Gain of function (targetable; e.g., EGFR)

~29% ~17%

Gain of function

(un‐targetable; e.g., CCNE1)

~54%	Loss of function
(no known driver; e.g., BRCA1)

Repare has identified several novel and proprietary targets to date

"…known cancer targets represent a small minority of strong cancer dependencies … synthetic lethal targets are particularly attractive as new targets…"

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