Monte Rosa Therapeutics : Corporate Presentation - August 2022

From Serendipity to Rational Design

Taking Molecular Glue Degraders to New Heights | August 2022

Forward-Looking Statements

These materials include express and implied "forward-looking statements," including forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward looking statements include all statements that are not historical facts, and in some cases, can be identified by terms such as "may," "might," "will," "could," "would," "should," "expect," "intend," "plan," "objective," "anticipate," "believe," "estimate," "predict," "potential," "continue," "ongoing," or the negative of these terms, or other comparable terminology intended to identify statements about the future. Forward-looking statements contained in herein include, but are not limited to, statements about our product development activities, including our expectations around MRT-2359 and the ongoing development of our QuEEN™ platform, and the advancement of our pipeline and the various products therein, our expectations of timing for FDA clearance of our IND for MRT-2359, our expectations of timing for initiation of our clinical trial for MRT-2359, our ability to initiate and the timing of initiation of additional lead optimization programs, and our expectations regarding our ability to nominate and the timing of our nominations of additional development candidates. By their nature, these statements are subject to numerous risks and uncertainties, including the impact that the current COVID-19 pandemic will have on our development activities and operations, as well as those risks and uncertainties set forth in our Annual Report on Form 10-K for the fourth quarter and full year ended December 31, 2021 filed, with the US Securities and Exchange Commission on March 29, 2022, and any subsequent filings, that could cause actual results, performance or achievement to differ materially and adversely from those anticipated or implied in the statements. You should not rely upon forward looking statements as predictions of future events. Although our management believes that the expectations reflected in our statements are reasonable, we cannot guarantee that the future results, performance or events and circumstances described in the forward-looking statements will be achieved or occur. Recipients are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date such statements are made and should not be construed as statements of fact. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, any future presentations or otherwise, except as required by applicable law. Certain information contained in these materials and any statements made orally during any presentation of these materials that relate to the materials or are based on studies, publications, surveys and other data obtained from third-party sources and our own internal estimates and research. While we believe these third- party studies, publications, surveys and other data to be reliable as of the date of these materials, we have not independently verified, and make no representations as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, no independent source has evaluated the reasonableness or accuracy of our internal estimates or research and no reliance should be made on any information or statements made in these materials relating to or based on such internal estimates and research.

2 These materials remain the proprietary intellectual property of Monte Rosa Therapeutics and should not be distributed or reproduced in whole or in part without the prior written consent of Monte Rosa Therapeutics.

Monte Rosa Therapeutics Highlights

Taking molecular glue degraders (MGDs) to new heights

Next-generation molecular	Targeting the undruggable	IND filed for GSPT1 program	World-class leadership & SAB
glue-based targeted protein	proteome via AI-based degron	with clinical development planned	with deep drug discovery know-
degradation platform	prediction & rational design of	in Myc-driven tumors	how and development expertise in
developing breakthrough small	highly selective MGDs		precision medicine
Five disclosed programs
molecule drugs that selectively
degrade therapeutically-relevant		targeting high unmet medical
proteins		needs in oncology and non-
		oncology indications

3

World-Class Leadership

Deep expertise in molecular glue discovery, drug development and precision medicine

Markus Warmuth, M.D.	Ajim Tamboli, CFA	Owen Wallace, Ph.D.	Sharon Townson, Ph.D.	John Castle, Ph.D.
Chief Executive Officer	Chief Financial Officer	Chief Scientific Officer	Chief Technology Officer	Chief Data Scientist

Filip Janku, M.D., Ph.D.	Jullian Jones, Ph.D., J.D., MBA	Silvia Buonamici, Ph.D.	Phil Nickson, Ph.D., J.D.	Jennifer Champoux,
Chief Medical Officer	Chief Business Officer	SVP, Drug Discovery Biology	General Counsel	SVP, Operations

4

Strong Cash Position and Investor Support

Over $455M raised since 2020 with top tier investors provides runway into late 2024

Series ASeries BSeries CIPO

	$32.5M		$96.0M		$95.0M		$255.6M*	$299.5M	Cash†
	April 14, 2020		September 14, 2020		March 11, 2021		June 28, 2021	as of June 30, 2022

* Aggregate IPO gross proceeds were approximately $255.6 million before deducting underwriting discounts and commissions and other offering expenses and include an additional $33.3 million in gross proceeds

5 the company received as part of its IPO from the full exercise of the underwriters' option to purchase up to an additional 1,755,000 shares of common stock at the public offering price of $19.00 per share.

† Includes cash, cash equivalents, restricted cash and marketable securities as of June 30, 2022