| --- | --- | --- | --- | |-------|-------|-------|-------| | | | | | | | | | | Forward Looking Statements This presentation and the accompanying oral presentation contain "forward-looking" statements that are based on our management's beliefs and assumptions and on information currently available to management. Forward-looking statements include all statements other than statements of historical fact contained in this presentation, including information concerning our future financial performance, business ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________ to ________ Commission File Number: 001-38662 SUTRO BIOPHARMA, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-0926186 (State ...

Company Strategy & Technology - Sutro Biopharma is expanding cell-free technology beyond ADCs, building strategic partnerships, and creating new modalities for extended value creation[8] - The company utilizes an industry-leading cell-free protein synthesis platform with GMP production yields consistent and scalable end-products[12] - Sutro's cell-free synthesis platform allows for the creation of hundreds of protein variants in weeks, enabling empirical selection of the best lead candidate[18] STRO-002 Program (Ovarian and Endometrial Cancers) - STRO-002 is a FolRα-targeting ADC with a DAR of 4, designed with a potentially dual mechanism of action[28] - In a Phase 1 dose-escalation study, 34 patients were treated at clinically active doses (≥ 2.9 mg/kg Q3W) of STRO-002[30] - In the RECIST-evaluable population (N=31), 10 patients met the criteria for response, with an objective response rate of 20%[36] - Clinical benefit was observed in a heavily pre-treated patient population, with a disease control rate of 74% at 12 weeks in the RECIST-evaluable population[43] STRO-001 Program (Lymphomas and Multiple Myeloma) - STRO-001 is a CD74-targeting ADC with a DAR of 2, designed to minimize bystander effects in hematological cancers[57] - In the NHL cohort, a total of 21 patients have been treated with STRO-001, and 18 patients were evaluable for response as of October 30, 2020[62] - Interim data showed partial responses in two DLBCL patients who had progressed on CAR-T therapy[67] Financial Status - The company reported $326.5 million in cash, cash equivalents, and marketable securities as of year-end 2020[73] - The projected cash runway extends into 2H 2023, not including potential monetization of Vaxcyte shares or future business development[73] - Sutro Biopharma has received approximately $398 million in funding from collaborators through year-end 2020[73]

| --- | --- | |-------|-------| | | | | | | Forward Looking Statements This presentation and the accompanying oral presentation contain "forward-looking" statements that are based on our management's beliefs and assumptions and on information currently available to management. Forward-looking statements include all statements other than statements of historical fact contained in this presentation, including information concerning our future financial performance, business plans and objectives, current and f ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 001-38662 SUTRO BIOPHARMA, INC. (Exact Name of Registrant as Specified in Its Charter) Delaware 47-0926186 (State or other jurisdiction o ...

| --- | --- | |-------|-------| | | | | | | This presentation and the accompanying oral presentation contain "forward-looking" statements that are based on our management's beliefs and assumptions and on information currently available to management. Forward-looking statements include all statements other than statements of historical fact contained in this presentation, including information concerning our future financial performance, business plans and objectives, current and future clinical and preclini ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________ to ________ Commission File Number: 001-38662 SUTRO BIOPHARMA, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-0926186 (S ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________ to ________ Commission File Number: 001-38662 SUTRO BIOPHARMA, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-0926186 (State ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________ to ________ Commission File Number: 001-38662 SUTRO BIOPHARMA, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-0926186 (State ...

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-K (Mark One) Commission File Number 001-38662 SUTRO BIOPHARMA, INC. (Exact Name of Registrant as Specified in Its Charter) Delaware 47-0926186 (State or other jurisdiction o ...