Monte Rosa Therapeutics, Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No. )

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☒ Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

☒ No fee required.

☐ Fee paid previously with preliminary materials.

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i) and 0-11

NOTICE OF 2025 ANNUAL MEETING OF STOCKHOLDERS

To be held online on June 13, 2025 at www.proxydocs.com/GLUE

Notice is hereby given that the 2025 Annual Meeting of Stockholders, or the Annual Meeting, of Monte Rosa Therapeutics, Inc., will be held online on June 13, 2025 at 8:30 a.m. Eastern Time. The Annual Meeting will be a virtual meeting, which will be conducted via live webcast. You will be able to attend the meeting online, vote electronically and submit questions by registering at www.proxydocs.com/GLUE prior to the deadline of June 11, 2025 at 5:00 p.m. Eastern Time.

The purpose of the Annual Meeting is the following:

To elect three Class I director nominees to our board of directors, to serve until the Company’s 2028 annual meeting of stockholders and until their successor has been duly elected and qualified, or until their earlier death, resignation or removal;

To ratify the appointment of Deloitte & Touche, LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2025; and

To transact any other business properly brought before the Annual Meeting or any adjournment or postponement of the Annual Meeting.

Stockholders of record at the close of business on April 16, 2025, the record date for the Annual Meeting, are entitled to notice of, and to vote at, the Annual Meeting or any adjournment or postponement of the Annual Meeting.

You can find more information on each of the matters to be voted on at the Annual Meeting, including information regarding the nominees for election to our board of directors, in the accompanying proxy statement. The board of directors recommends a vote “FOR” the election of the three nominees for Class I directors and “FOR” the ratification of the appointment of our independent registered public accounting firm for the fiscal year ending December 31, 2025, as disclosed in the accompanying proxy statement.

We are pleased to take advantage of the rules of the Securities and Exchange Commission, or the SEC, which allow companies to distribute their proxy materials over the Internet under the “notice and access” approach. As a result, we are mailing to our stockholders a Notice of Internet Availability of Proxy Materials, or Notice of Availability, instead of a paper copy of our proxy materials and our Annual Report to Stockholders for the fiscal year ended December 31, 2024, or the 2024 Annual Report. We will mail the Notice of Availability on or about May 2, 2025, and it contains instructions on how to access those documents and to cast your vote over the Internet. This process allows us to provide our stockholders with the information they need on a more timely basis, while reducing the environmental impact and lowering the costs of printing and distributing our proxy materials. If you would like to receive a printed copy of our proxy materials, including our proxy statement, our 2024 Annual Report and a form of proxy card, free of charge, please follow the instructions on the Notice of Availability.

In order to attend the Annual Meeting virtually, you must register in advance at www.proxydocs.com/GLUE prior to the deadline of June 11, 2025 at 5:00 p.m. Eastern Time. Upon entry of your control number and other required information, you will receive further instructions via email that provide you access to the Annual Meeting and the ability to vote and submit questions during the Annual Meeting. Please see the “General Information” section of the proxy statement at www.proxydocs.com/GLUE for more information. Beneficial owners of shares held in street name will need to register at www.proxydocs.com/GLUE, and additionally must follow the instructions in the voting instructions form by the broker, bank or other nominee that holds their shares. Upon completing your registration, you will receive further instructions via email, including your unique link to access the Annual Meeting and to submit questions this notice for more details regarding the logistics of the virtual Annual Meeting, including the ability of stockholders to submit questions during the Annual Meeting, and technical details and support related to accessing the virtual platform. You will not be able to attend the Annual Meeting in person.

Your vote is important. Whether or not you are able to attend the Annual Meeting virtually and vote your shares online, it is important that your shares be represented. To ensure that your vote is recorded promptly, please vote as soon as possible, even if you plan to attend the Annual Meeting, by submitting your proxy over the Internet or by telephone as described in the instructions included in the Notice of Availability or by signing, dating and returning the proxy card.

By order of the Board of Directors,

/s/ Markus Warmuth

Markus Warmuth

President and Chief Executive Officer

Boston, Massachusetts

April 25, 2025

Table of Contents

i