Monte Rosa Therapeutics : Corporate Presentation - May 2024

Forward-Looking Statements

This communication includes 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 herein include, but are not limited to, statements about our product development activities, our ability to grow our product pipeline, our ongoing clinical development of our GSPT1 degrader referred to as MRT-2359, including our expectations for the nature, significance, and timing for our disclosure of any initial data from our Phase 1/2 clinical trial of MRT-2359 in MYC-driven solid tumors, statements the Company's QuEENTM discovery engine and the Company's view of its potential to identify degradable protein targets and rationally design MGDs with unprecedented selectivity, statements about the potential applications of our rationally designed MGDs in oncology, immunology, neuroscience and other therapeutic areas, statements about our collaboration with Roche, statements about the advancement and timeline of our preclinical and clinical programs, pipeline and the various products therein, including (i) our product development activities and our ongoing clinical development of MRT-2359, including our expectations to announce the recommended Phase 2 dose later in the second quarter of 2024, the timing for our disclosure of any initial data from our Phase 1 clinical trial of MRT-2359 in the second half of 2024, and our plans to initiate the Phase 2 portion of the study, (ii) the ongoing development of MRT-6160, including its rapid advancement with Phase 1 initiation expected in mid-2024, planned submission of an IND to the FDA for MRT-6160 in the second quarter of 2024, our expectations of timing for initiation of a Phase 1 single ascending dose / multiple ascending dose (SAD/MAD) study in mid-2024 and the timing for our disclosure of Phase 1 clinical data of MRT-6160 in the first quarter of 2025 and our expectation to initiate POC studies for MRT-6160 in autoimmune/inflammatory diseases, (iii) our ongoing development of MRT-8102, including our expectations to submit an IND to the FDA in the first quarter of 2025, statements about the timing for a clinical readout of data from a Phase 1 SAD/MAD study for MRT-8102 and our expectations of timing for clinical advancement for MRT-8102, and (iv) our expectations to nominate a development candidate for the CDK2 preclinical program in 2024, , statements around the advancement and application of our platform, and statements concerning our expectations regarding our ability to nominate and the timing of our nominations of additional targets, product candidates, and development candidates, as well as our expectations of success for our programs and the strength of our financial position, our use of capital, expenses and other financial results in the future, availability of funding for existing programs, ability to fund operations into the first half of 2026, among others. By their nature, these statements are subject to numerous risks and uncertainties, including those risks and uncertainties set forth in our most recent Annual Report on Form 10-K for the year ended December 31, 2023, filed with the U.S. Securities and Exchange Commission on March 14, 2024, 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.

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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 - Company Overview

Taking molecular glue degraders (MGDs) to new heights

Three Ways to Eliminate a Disease-Causing Protein

MGDs can directly and precisely target proteins that cause disease

MGD

DNA mRNA protein

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Our Molecular Glue Degraders (MGDs) Edit the Proteome

Ubiquitin chain

Neosubstrate

(target protein)

Neosubstrate

MGDUbiquitination

MGD

Ligase

Proteasome-mediated

degradation of neosubstrate

Monte Rosa's rationally designed MGDs have potential applications in Oncology,

Molecular Glue Degraders (MGDs) - A Highly Differentiated Modality

Advantages of large molecule modalities with orally dosed small molecules

MGD

POI = protein of interest

Monte Rosa Therapeutics - Key Firsts and Accomplishments

From serendipity to rational design of MGDs

Built a proprietary molecular glue-based targeted protein degradation platform developing breakthrough

therapeutics that selectively degrade disease-causing proteins

Established a target-centric drug discovery approach combining experimentation with AI enabling rational design of highly potent and selective MGDs

Presented interim data from Phase 1/2 trial of GSPT1-directed MGD MRT-2359 for the treatment of MYC- driven tumors; optimal pharmacodynamics*, favorable safety profile and initial clinical activity observed

Progressed VAV1 MGD MRT-6160 and NEK7 MGD MRT-8102 into IND enabling studies; MRT-6160is the first known MGD specifically developed for a non-oncologyindication

Advanced several additional highly credentialed targets as amenable to degradation through our platform including CDK2 and multiple discovery targets; began expanding approach to E3 ligases beyond cereblon

Established validating discovery collaboration with Roche in oncology and neurological diseases

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* Based on optimal PD modulation in preclinical studies