Repare Therapeutics : Corporate Presentation Q1 2023

Repare Therapeutics

Insight that enriches. Precision that empowers.

CORPORATE PRESENTATION

Q1 2023

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-6306 and camonsertib; the expected timing of program updates and data disclosures; the timing of filing INDs and other regulatory documents; 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 Annual Report on Form 10-K filed with the SEC on February 28, 2023, 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 precision oncology company focused on synthetic lethality

RP-6306

C

RP-6306, a first-in-class, oral	Robust pipeline
PKMYT1 inhibitor, drives	of SL-based therapeutic
genomic instability in CCNE1-	opportunities, including
amplified tumors with Ph 1	Polθ and a pipeline
monotherapy and multiple	of advanced preclinical
combination trials ongoing	opportunities

Camonsertib (RP-3500 /							Proprietary genome-wide
RG6526), a potential							CRISPR-enabled SNIPRx
best-in-class ATR							platform, focused on genomic
inhibitor with durable								instability and DNA damage
responses and clinical							repair, enabling novel target
benefit in Ph 1/2 and							identification and differentiated
strategic validation through							patient selection insights
Roche partnership

Balance Sheet of $344M funds Repare through multiple value-creatingmilestones into 2026

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Proven experience in drug discovery and development

Leadership Team

Lloyd M. Segal	Steve Forte, CPA	Michael Zinda, PhD	Maria Koehler, MD, PhD	Cameron Black, PhD	Philip Herman	Kim A. Seth, PhD
President & CEO	Chief Financial Officer	Chief Scientific Officer	Chief Medical Officer	Head of Discovery	Head of Commercial	Chief Business Officer
					& New Product Dev

Scientific Founders

	Daniel Durocher, PhD		Agnel Sfeir, PhD	Frank Sicheri, PhD
	Developed CRISPR SL platform		DDR and cancer pathway	 Globally recognized structural
	Deep DNA repair knowledge		investigator	biologist, expert in eukaryotic cell
	Lunenfeld-Tanenbaum Research Institute		Pioneer in Polθ, genome instability	signaling, drug mechanism of action
	(LTRI) & professor at University of Toronto		Professor, MSKCC	 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%

~54%

Gain of function (un-targetable; e.g., CCNE1)

Loss of function

(no known driver; e.g., BRCA1)

"…known cancer targets represent a small minority of strong cancer dependencies

• synthetic lethal targets are particularly attractive as new targets…"

Repare has identified several novel and proprietary targets to date

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