Monte Rosa Therapeutics, Inc.

Previous wording

Since our inception, we have focused substantially all of our efforts and financial resources on developing our proprietary QuEENTM discovery engine, our proprietary MGD library and our initial pipeline of product candidates. To date, we have financed our operations primarily through the issuance and sale of convertible promissory notes, and our convertible preferred stock to outside investors in private equity financings, public offerings of our common stock or warrants to purchase common stock, registered direct offerings, and our collaboration agreements with Roche and Novartis. From our inception through the date hereof, we raised an aggregate of $1.3 billion of gross proceeds from such transactions. As of June 30, 2026, our cash, cash equivalents, restricted cash and marketable securities were $626.0 million. We have incurred net losses in each year since our inception, and we had an accumulated deficit of $565.1 million as of June 30, 2026. For the six months ended June 30, 2026, we reported a net loss of $87.9 million. For the year ended December 31, 2025, we reported a net losses of $38.6 million. Substantially all of our operating losses have resulted from costs incurred in connection with our research and initial pipeline programs and from general and administrative costs associated with our operations. We expect to continue to incur significant expenses and increasing operating losses over the next several years and for the foreseeable future. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on our stockholders’ deficit and working capital. We expect our expenses to significantly increase in connection with our ongoing activities, as we:

Current wording

Since our inception, we have focused substantially all of our efforts and financial resources on developing our proprietary QuEENTM discovery engine, our proprietary MGD library and our initial pipeline of product candidates. To date, we have financed our operations primarily through the issuance and sale of convertible promissory notes, and our convertible preferred stock to outside investors in private equity financings, public offerings of our common stock or warrants to purchase common stock, registered direct offerings, and our collaboration agreements with Roche and Novartis. From our inception through the date hereof, we raised an aggregate of $1.4 billion of gross proceeds from such transactions. As of September 30, 2026, our cash, cash equivalents, restricted cash and marketable securities were $582.6 million. We have incurred net losses in each year since our inception, and we had an accumulated deficit of $562.1 million as of September 30, 2026. For the nine months ended September 30, 2026, we reported a net loss of $84.8 million. For the year ended December 31, 2025, we reported a net loss of $38.6 million. Substantially all of our operating losses have resulted from costs incurred in connection with our research and initial pipeline programs and from general and administrative costs associated with our operations. We expect to continue to incur significant expenses and increasing operating losses over the next several years and for the foreseeable future. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on our stockholders’ deficit and working capital. We expect our expenses to significantly increase in connection with our ongoing activities, as we:

Previous wording

conduct our clinical trial for MRT-2359, our MGD product candidate targeting GSPT1;

Current wording

conduct our clinical trials for MRT-2359, our MGD product candidate targeting GSPT1, including MODeFIRe-1, our Phase 2 study of MRT-2359 in combination with apalutamide;

Previous wording

finalize our Phase 1 clinical trial and advance our Phase 2 clinical trial for MRT-8102, our NEK7-directed MGD being developed for the treatment of inflammatory conditions driven by the NLRP3 inflammasome, IL-1β, and IL-6;

Current wording

advance our Phase 2 clinical trials for MRT-8102, our NEK7-directed MGD being developed for the treatment of inflammatory conditions driven by the NLRP3 inflammasome, IL-1β, and IL-6, including GFORCE-2, GEMINI-1, and GALAXY-1;

Previous wording

prepare and submit IND applications with the FDA for other current and future product candidates;

Current wording

prepare and submit IND applications with the U.S. Food and Drug Administration, or FDA, for other current and future product candidates;

Previous wording

During the fiscal quarter ended on June 30, 2026, none of our directors and officers (as defined in Rule 16a-1(f) under the Exchange Act)adopted, modified orterminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Item 408(a) of Regulation S-K, except as described in the table below.

Current wording

During the fiscal quarter ended on September 30, 2026, none of our directors and officers (as defined in Rule 16a-1(f) under the Exchange Act)adopted, modified orterminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Item 408(a) of Regulation S-K.