CBFA2T3

- Sutro will present updated data from the ongoing Phase 1b study of luvelta in combination with bevacizumab in a poster presentation at ESMO 2024; expansion study is ongoing with data expected in the first half of 2025 - - REFRαME-O1 Part 2 (randomized portion) of the Phase 3 trial of luvelta for treatment of platinum-resistant ovarian cancer (PROC) is underway - - REFRαME-P1, a registration-enabling trial of luvelta for pediatric patients with CBFA2T3::GLIS2 (CBF/GLIS; RAM phenotype) AML, is expected to be initiated in the second half of 2024 - - A Phase 2 trial of luvelta for the treatment of NSCLC is expected to initiate in the second half of 2024, with initial data expected in the first half of 2025 - - As of June 30, 2024, Sutro had $426.0 million, composed of cash, cash equivalents and marketable securities of $375.6 million and approximately 0.7 million shares of Vaxcyte common stock with a fair value of $50.4 million - SOUTH SAN FRANCISCO, Calif., Aug. 13, 2024 (GLOBE NEWSWIRE) -- Sutro Biopharma, Inc. (Sutro or the Company) (NASDAQ: STRO), a clinical-stage oncology company pioneering site-specific and novel-format antibody drug conjugates (ADCs), today reported its financial results for the second quarter of 2024, its recent business highlights, and a preview of select anticipated milestones. “We continue to make meaningful progress with the development of luvelta across multiple indications, including enrollment of a patient expansion cohort in combination with bevacizumab, nearing initiation of our second registration-enabling trial, REFRaME-P1, for pediatric patients with a rare form of acute myeloid leukemia (AML) and approaching site activation of a Phase 2 trial in non-small cell lung cancer (NSCLC),” said Bill Newell, Sutro’s Chief Executive Officer. “We plan to share supplemental data from our Phase 1b trial of luvelta in combination with bevacizumab at the ESMO meeting in September.” Mr. Newell added, “We are off to strong start in our new partnership with Ipsen for STRO-003 and continue to advance our preclinical pipeline of next-generation ADCs, including our tissue-factor targeting exatecan ADC, STRO-004. In parallel, we are exploring new partnership opportunities to maximize the potential of our platform and pipeline, led by our new Chief Business Development Officer Barbara Leyman. Additionally, we are delighted to welcome Sukhi Jagpal to our Board, as he brings a wealth of invaluable financial and strategic expertise.” Recent Business Highlights and Select Anticipated Milestones Luveltamab Tazevibulin (luvelta), FRα-Targeting ADC Franchise: Sutro will present updated data from the Phase 1b study of luvelta in combination with bevacizumab for patients with ovarian cancer in a poster presentation at the European Society for Medical Oncology (ESMO) Congress 2024 to be held September 13-17 in Barcelona, Spain. Title: Luveltamab tazevibulin, an antifolate receptor alpha (FRα) antibody-drug conjugate (ADC), in combination with bevacizumab (bev) in patients with recurrent high-grade epithelial ovarian cancer (EOC): STRO-002-GM2 phase 1 studyDate: Saturday, September 14, 2024 Part 2 (randomized portion) of the Phase 3 trial, REFRαME-O1, for treatment of platinum-resistant ovarian cancer (PROC), is underway.REFRαME-P1, a registration-enabling trial for pediatric patients with CBFA2T3::GLIS2 (CBF/GLIS; RAM phenotype) AML, is expected to be initiated in the second half of 2024.A Phase 2 expansion study in combination with bevacizumab is ongoing, with data expected in the first half of 2025.A Phase 2 trial for the treatment of NSCLC is expected to initiate in the second half of 2024, with initial data expected in the first half of 2025. Additional Pipeline Development and Collaboration Updates: In April 2024, Sutro announced a global licensing agreement for STRO-003, a ROR1-targeting ADC, with Ipsen.Sutro plans to submit an IND for STRO-004 in 2025.Sutro continues to seek to maximize the value of its proprietary cell-free platform by working with partners on programs in multiple disease spaces and geographies and has generated from collaborators an aggregate of approximately $970 million in payments through June 30, 2024, including equity investments. Corporate Updates: In August, Sutro strengthened its Board of Directors with the appointment of Sukhi Jagpal, MBA, CPA, CBV. Mr. Jagpal brings 20 years of experience in the life sciences industry, with expertise in financial management, communication, and organizational effectiveness, including financial analysis, mergers and acquisitions, and cost optimization.In July, Sutro appointed Barbara Leyman, Ph.D., as Chief Business Development Officer, with a focus on building value and executing the Company’s business development strategy, in addition to serving on Sutro’s senior management team. Upcoming Events: Sutro will participate in two upcoming investor conferences. Webcasts of the presentations will be accessible through the News & Events page of the Investor Relations section of the Company’s website at www.sutrobio.com. Archived replays will be available for at least 30 days after the events. Wedbush PacGrow Healthcare Conference in New York, August 13-14, 2024Wells Fargo Healthcare Conference in Boston, September 4-6, 2024 Second Quarter 2024 Financial Highlights Cash, Cash Equivalents and Marketable Securities and Vaxcyte Common StockAs of June 30, 2024, Sutro had $426.0 million, composed of cash, cash equivalents and marketable securities of $375.6 million and approximately 0.7 million shares of Vaxcyte common stock with a fair value of $50.4 million. Unrealized Gain from Increase in Value of Vaxcyte Common StockThe non-operating, unrealized gain of $4.8 million for the quarter ended June 30, 2024 was due to the increase since March 31, 2024 in the estimated fair value of Sutro’s holdings of Vaxcyte common stock. Vaxcyte common stock held by Sutro will be remeasured at fair value based on the closing price of Vaxcyte’s common stock on the last trading day of each reporting period, with any non-operating, unrealized gains and losses recorded in Sutro’s statements of operations. RevenueRevenue was $25.7 million for the quarter ended June 30, 2024, as compared to $10.4 million for the same period in 2023, with the 2024 amount related principally to the Astellas collaboration and the Vaxcyte agreement. Future collaboration and license revenue under existing agreements, and from any additional collaboration and license partners, will fluctuate as a result of the amount and timing of revenue recognition of upfront, milestones, and other agreement payments. Operating ExpensesTotal operating expenses for the quarter ended June 30, 2024 were $74.4 million, as compared to $56.6 million for the same period in 2023. The 2024 quarter includes non-cash expenses for stock-based compensation of $6.2 million and depreciation and amortization of $1.8 million, as compared to $6.7 million and $1.7 million, respectively, in the comparable 2023 period. Total operating expenses for the quarter ended June 30, 2024 were comprised of research and development expenses of $62.0 million and general and administrative expenses of $12.4 million. About Sutro Biopharma Sutro Biopharma, Inc., is a clinical-stage company relentlessly focused on the discovery and development of precisely designed cancer therapeutics, to transform what science can do for patients. Sutro’s fit-for-purpose technology, including cell-free XpressCF®, provides the opportunity for broader patient benefit and an improved patient experience. Sutro has multiple clinical stage candidates, including luveltamab tazevibulin, or luvelta, a registrational-stage folate receptor alpha (FolRα)-targeting ADC in clinical studies. A robust pipeline, coupled with high-value collaborations and industry partnerships, validates Sutro’s continuous product innovation. Sutro is headquartered in South San Francisco. For more information, follow Sutro on social media @Sutrobio, or visit www.sutrobio.com. Forward-Looking Statements This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, anticipated preclinical and clinical development activities, including enrollment and site activation; timing of announcements of clinical results, trial initiation, and regulatory filings; outcome of regulatory decisions; potential benefits of luvelta and the Company’s other product candidates and platform; timing of payments under our collaboration agreements; potential expansion into other indications and combinations, including the timing and development activities related to such expansion; potential market opportunities for luvelta and the Company’s other product candidates; and the Company’s expected cash runway. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Although the Company believes that the expectations reflected in such forward-looking statements are reasonable, the Company cannot guarantee future events, results, actions, levels of activity, performance or achievements, and the timing and results of biotechnology development and potential regulatory approval is inherently uncertain. Forward-looking statements are subject to risks and uncertainties that may cause the Company’s actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to the Company’s ability to advance its product candidates, the receipt and timing of potential regulatory designations, approvals and commercialization of product candidates and the Company’s ability to successfully leverage Fast Track designation, the market size for the Company’s product candidates to be smaller than anticipated, clinical trial sites, supply chain and manufacturing facilities, the Company’s ability to maintain and recognize the benefits of certain designations received by product candidates, the timing and results of preclinical and clinical trials, the Company’s ability to fund development activities and achieve development goals, the Company’s ability to protect intellectual property, the value of the Company’s holdings of Vaxcyte common stock, and the Company’s commercial collaborations with third parties and other risks and uncertainties described under the heading “Risk Factors” in documents the Company files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this press release, and the Company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof. Sutro Biopharma, Inc.Selected Statements of Operations Financial Data(Unaudited)(In thousands, except share and per share amounts) Three Months EndedSix Months Ended June 30,June 30, 2024 2023 2024 2023 Revenues$25,706 $10,412 $38,714 $23,086 Operating expenses Research and development 62,020 41,592 118,898 80,991 General and administrative 12,371 14,999 25,092 30,511 Total operating expenses 74,391 56,591 143,990 111,502 Loss from operations (48,685) (46,179) (105,276) (88,416)Interest income 4,911 2,842 9,007 5,402 Unrealized gain on equity securities 4,808 8,321 8,487 1,329 Non-cash interest expense related to the sale of future royalties (7,286) (442) (14,470) (442)Interest and other income (expense), net (1,758) (2,915) (3,971) (5,901)Loss before provision for income taxes (48,010) (38,373) (106,223) (88,028)Provision for income taxes 8 151 8 546 Net loss$(48,018) $(38,524) $(106,231) $(88,574)Net loss per share, basic and diluted$(0.59) $(0.64) $(1.49) $(1.49)Weighted-average shares used in computing basic and diluted loss per share 81,224,628 60,339,475 71,341,211 59,535,918 Sutro Biopharma, Inc.Selected Balance Sheets Financial Data(Unaudited)(In thousands) June 30, 2024(1) December 31, 2023(2) Assets Cash, cash equivalents and marketable securities$375,568 $333,681 Investment in equity securities 50,424 41,937 Accounts receivable 6,950 36,078 Property and equipment, net 19,414 21,940 Operating lease right-of-use assets 20,333 22,815 Other assets 16,354 14,285 Total Assets$489,043 $470,736 Liabilities and Stockholders’ Equity Accounts payable, accrued expenses and other liabilities$50,782 $64,293 Deferred revenue 95,654 74,045 Operating lease liability 26,526 29,574 Debt - 4,061 Deferred royalty obligation related to the sale of future royalties 163,905 149,114 Total liabilities 336,867 321,087 Total stockholders’ equity 152,176 149,649 Total Liabilities and Stockholders’ Equity$489,043 $470,736 (1) The condensed balance sheet as of June 30, 2024 was derived from the unaudited financial statements included in the Company's Quarterly Report on Form 10-Q for the quarter ended June 30, 2024, filed with the Securities and Exchange Commission on August 13, 2024.(2) The condensed balance sheet as of December 31, 2023 was derived from the unaudited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023, filed with the Securities and Exchange Commission on March 25, 2024.

- Investigational New Drug application for non-small cell lung cancer trial with luvelta cleared by U.S. Food and Drug Administration; Phase 2 on track to begin dosing in the second half of 2024 - - Patient expansion phase well underway in Phase 2 study of luvelta in combination with bevacizumab; enrollment is expected to complete in the first half of 2024 - - The randomized portion of REFRαME-O1, the registration-enabling study of luvelta for patients with platinum-resistant ovarian cancer, is active and enrolling - - As of March 31, 2024, Sutro had cash and investments of $267.6 million and shares of Vaxcyte common stock valued at $45.6 million - - In April, Sutro further bolstered its cash position with $75 million in upfront payments and an equity investment from licensing exclusive global rights to STRO-003 to Ipsen and $75 million raised in an underwritten offering of common stock - SOUTH SAN FRANCISCO, Calif., May 13, 2024 (GLOBE NEWSWIRE) -- Sutro Biopharma, Inc (Sutro or the Company) (NASDAQ: STRO), a clinical-stage oncology company pioneering site-specific and novel-format antibody drug conjugates (ADCs), today reported its financial results for the first quarter of 2024, its recent business highlights, and a preview of select anticipated milestones. “The Sutro team executed on multiple fronts in the first quarter of 2024, advancing luvelta through the clinic in multiple indications of high unmet need, continuing to progress our pipeline and collaboration programs, and establishing a new licensing relationship with Ipsen. The upfront funding from the Ipsen deal and our recent financing also augmented our strong cash position,” said Bill Newell, Sutro’s Chief Executive Officer. “We plan to deliver on important catalysts throughout 2024, reporting on expanded patient data with luvelta in combination with bevacizumab, the initiation of a registrational trial for pediatric patients with a rare form of acute myeloid leukemia (AML), and a Phase 2 trial in non-small cell lung cancer (NSCLC). We continue to build upon our momentum and are well positioned on our goal to rapidly deliver precisely designed ADCs to patients in need.” RecentBusinessHighlightsand Select AnticipatedMilestones Luveltamab Tazevibulin (luvelta), FolRα-Targeting ADC Franchise: Part 1 (dose-optimization) of the registration-directed trial, REFRαME-O1, for treatment of platinum-resistant ovarian cancer (PROC), has completed enrollment. Part 2 (randomized portion) is now enrolling, with an anticipated ~140 sites in ~20 countries planned to be opened by the end of 2024. Enrollment of REFRαME-P1, a registration-enabling trial for pediatric patients with CBFA2T3::GLIS2 (CBF/GLIS; RAM phenotype) AML, is expected to be initiated in the second half of 2024. An Investigational New Drug (IND) application for the treatment of NSCLC has been cleared by U.S. Food and Drug Administration (FDA). The Phase 2 trial is expected to begin enrolling patients in the second half of 2024. Initial data is expected in the first half of 2025. A Phase 2 expansion study in combination with bevacizumab is well underway. Enrollment is expected to be complete in the first half of 2024. Additional Pipeline Development and Collaboration Updates: In April 2024, Sutro announced a global licensing agreement for STRO-003, a ROR1-targeting ADC, with Ipsen. Sutro is eligible to receive up to $899 million in upfront and potential milestone payments, including up to $92 million in near-term payments, of which $75 million, including an equity investment, have been received in April. Sutro is also eligible to receive tiered royalties ranging from low double-digit to mid-teen digit percentages on annual global sales of STRO-003. Sutro plans to submit an IND for STRO-004, a tissue factor-targeting ADC, in 2025. Sutro continues to seek to maximize the value of its proprietary cell-free platform by working with partners on programs in multiple disease spaces and geographies and has generated from collaborators an aggregate of approximately $864 million in payments through March 31, 2024, including equity investments. Corporate Updates: Additionally, Sutro strengthened its cash position with an underwritten offering of 14,478,764 shares of its common stock at a price of $5.18 per share, resulting in gross proceeds of $75.0 million. The offering was led by a high-quality group of new and existing healthcare-focused institutional investors. Upcoming Events: Sutro will participate in two upcoming investor conferences. Webcasts of the presentations will be accessible through the News & Events page of the Investor Relations section of the Company’s website at Archived replays will be available for at least 30 days after the events. The Citizens JMP Life Sciences Conference in New York, May 13-14, 2024 Jefferies Healthcare Conference in New York, June 5-6, 2024 First Quarter 2024FinancialHighlights Cash, Cash Equivalents and Marketable Securities As of March 31, 2024, Sutro had cash, cash equivalents and marketable securities of $267.6 million, and approximately 0.7 million shares of Vaxcyte common stock with a fair value of $45.6 million. Unrealized Gain from Increase in Value of Vaxcyte Common Stock The non-operating, unrealized gain of $3.7 million for the quarter ended March 31, 2024 was due to the increase since December 31, 2023 in the estimated fair value of Sutro’s holdings of Vaxcyte common stock. Vaxcyte common stock held by Sutro will be remeasured at fair value based on the closing price of Vaxcyte’s common stock on the last trading day of each reporting period, with any non-operating, unrealized gains and losses recorded in Sutro’s statements of operations. Revenue Revenue was $13.0 million for the quarter ended March 31, 2024, as compared to $12.7 million for the same period in 2023, with the 2024 amount related principally to the Astellas collaboration, and the Tasly and Vaxcyte agreements. Future collaboration and license revenue under existing agreements, and from any additional collaboration and license partners, will fluctuate as a result of the amount and timing of revenue recognition of upfront, milestones, and other agreement payments. Operating Expenses Total operating expenses for the quarter ended March 31, 2024 were $69.6 million, as compared to $54.9 million for the same period in 2023. The 2024 quarter includes non-cash expenses for stock-based compensation of $6.1 million and depreciation and amortization of $1.8 million, as compared to $6.0 million and $1.6 million, respectively, in the comparable 2023 period. Total operating expenses for the quarter ended March 31, 2024 were comprised of research and development expenses of $56.9 million and general and administrative expenses of $12.7 million. About Sutro Biopharma Sutro Biopharma, Inc., is a clinical-stage company relentlessly focused on the discovery and development of precisely designed cancer therapeutics, to transform what science can do for patients. Sutro’s fit-for-purpose technology, including cell-free XpressCF®, provides the opportunity for broader patient benefit and an improved patient experience. Sutro has multiple clinical stage candidates, including luveltamab tazevibulin, or luvelta, a registrational-stage folate receptor alpha (FolRα)-targeting ADC in clinical studies. A robust pipeline, coupled with high-value collaborations and industry partnerships, validates Sutro’s continuous product innovation. Sutro is headquartered in South San Francisco. For more information, follow Sutro on social media @Sutrobio, or visit Forward-Looking Statements This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, anticipated preclinical and clinical development activities, including enrollment and site activation; timing of announcements of clinical results, trial initiation, and regulatory filings; outcome of regulatory decisions; potential benefits of luvelta and the Company’s other product candidates and platform; timing of payments under our collaboration agreements; potential expansion into other indications and combinations, including the timing and development activities related to such expansion; potential market opportunities for luvelta and the Company’s other product candidates; and the Company’s expected cash runway. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Although the Company believes that the expectations reflected in such forward-looking statements are reasonable, the Company cannot guarantee future events, results, actions, levels of activity, performance or achievements, and the timing and results of biotechnology development and potential regulatory approval is inherently uncertain. Forward-looking statements are subject to risks and uncertainties that may cause the Company’s actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to the Company’s ability to advance its product candidates, the receipt and timing of potential regulatory designations, approvals and commercialization of product candidates and the Company’s ability to successfully leverage Fast Track designation, the market size for the Company’s product candidates to be smaller than anticipated, clinical trial sites, supply chain and manufacturing facilities, the Company’s ability to maintain and recognize the benefits of certain designations received by product candidates, the timing and results of preclinical and clinical trials, the Company’s ability to fund development activities and achieve development goals, the Company’s ability to protect intellectual property, the value of the Company’s holdings of Vaxcyte common stock, and the Company’s commercial collaborations with third parties and other risks and uncertainties described under the heading “Risk Factors” in documents the Company files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this press release, and the Company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof. Contact Emily White Sutro Biopharma (650) 823-7681 ewhite@sutrobio.com Sutro Biopharma, Inc. Selected Statements of Operations Financial Data (Unaudited) (In thousands, except share and per share amounts) Three Months Ended March 31, 2024 2023 Revenue $ 13,008 $ 12,674 Operating expenses Research and development 56,878 39,399 General and administrative 12,721 15,512 Total operating expenses 69,599 54,911 Loss from operations (56,591 ) (42,237 ) Interest income 4,096 2,560 Unrealized gain (loss) on equity securities 3,679 (6,992 ) Non-cash interest expense related to the sale of future royalties (7,184 ) - Interest and other income (expense), net (2,213 ) (2,986 ) Loss before provision for income taxes (58,213 ) (49,655 ) Provision for income taxes - 395 Net loss $ (58,213 ) $ (50,050 ) Net loss per share, basic and diluted $ (0.95 ) $ (0.85 ) Weighted-average shares used in computing basic and diluted loss per share 61,457,793 58,723,432 Sutro Biopharma, Inc. Selected Balance Sheets Financial Data (Unaudited) (In thousands) March 31, 2024(1) December 31, 2023(2) Assets Cash, cash equivalents and marketable securities $ 267,602 $ 333,681 Investment in equity securities 45,616 41,937 Accounts receivable 31,300 36,078 Property and equipment, net 20,630 21,940 Operating lease right-of-use assets 21,594 22,815 Other assets 16,660 14,285 Total Assets $ 403,402 $ 470,736 Liabilities and Stockholders’ Equity Accounts payable, accrued expenses and other liabilities $ 54,028 $ 64,293 Deferred revenue 66,815 74,045 Operating lease liability 28,070 29,574 Debt - 4,061 Deferred royalty obligation related to the sale of future royalties 156,465 149,114 Total liabilities 305,378 321,087 Total stockholders’ equity 98,024 149,649 Total Liabilities and Stockholders’ Equity $ 403,402 $ 470,736 (1) The condensed balance sheet as of March 31, 2024 was derived from the unaudited financial statements included in the Company's Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, filed with the Securities and Exchange Commission on May 13, 2024. (2) The condensed balance sheet as of December 31, 2023 was derived from the unaudited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023, filed with the Securities and Exchange Commission on March 25, 2024.

- Sutro highlighted luveltamab tazevibulin (luvelta) in a January 2024 investor webcast, describing the broad opportunity to address unmet needs in multiple FolRα-expressing cancers - - Compelling anti-leukemic activity of luvelta in pediatric patients with relapsed/refractory CBF2AT3-GLIS2 AML treated under Compassionate Use shown in data presented at ASH 2023 - - Jane Chung promoted to President and Chief Operating Officer in November 2023 - - As of year-end 2023, Sutro had cash and investments of $333.7 million and shares of Vaxcyte common stock valued at $41.9 million, which together provide a projected cash runway into the second half of 2025 - SOUTH SAN FRANCISCO, Calif., March 25, 2024 (GLOBE NEWSWIRE) -- Sutro Biopharma, Inc. (Sutro or the Company) (NASDAQ: STRO), a clinical-stage oncology company pioneering site-specific and novel-format antibody drug conjugates (ADCs), today reported its financial results for the full year 2023, its recent business highlights, and a preview of select anticipated milestones. “The year 2023 was pivotal for Sutro, with the initiation of REFRαME-O1, our registration-directed study of luvelta for platinum-resistant ovarian cancer (PROC) patients, further validating our next-generation ADC capabilities. In addition, we advanced our earlier stage programs, strengthened our management team, and bolstered our already strong cash position with additional non-dilutive capital,” said Bill Newell, Sutro’s Chief Executive Officer. “We look forward to continuing the momentum in 2024, with the initiation of a second registration-directed trial with luvelta, REFRαME-P1, for pediatric patients with CBF/GLIS AML, and two additional planned INDs. I am delighted with the strides we are taking towards meaningfully impacting the lives of cancer patients in need.” Recent Business Highlights and Select Anticipated Milestones STRO-002, International Nonproprietary Name, “luveltamab tazevibulin,” abbreviated as “luvelta,” FolRα-Targeting ADC Franchise: In January 2024, Sutro hosted an investor webcast highlighting luvelta’s broad opportunity to address unmet needs in several FolRα-expressing cancers, including platinum-resistant ovarian cancer (PROC), endometrial cancer, CBFA2T3::GLIS2 (CBF/GLIS; RAM phenotype) acute myeloid leukemia (AML), and non-small cell lung cancer (NSCLC).The registration-directed trial, REFRαME-O1, for treatment of PROC is enrolling, with an anticipated ~140 sites in ~20 countries to be opened by the end of 2024. Enrollment of Part 1 of the trial is expected to be completed in the first half of 2024.In December 2023, data demonstrating anti-leukemic activity with luvelta, either as a single agent or in combination, in pediatric patients with CBF/GLIS AML, were presented at the 65th American Society of Hematology Annual Meeting and Exposition (ASH 2023), including complete remission in 42% of patients with CBF/GLIS AML with ≥5% blasts and in 75% of pediatric patients with CBF/GLIS AML with <5% blasts.Enrollment of REFRαME-P1, a registration-enabling trial for pediatric patients with CBF/GLIS AML, is expected to be initiated in the second half of 2024.An Investigational New Drug (IND) application submission is planned for treatment of non-small cell lung cancer (NSCLC) in the first half of 2024.Continued clinical development is planned in combination with bevacizumab for the treatment of ovarian cancer and in endometrial cancer, as resources permit. Additional Pipeline Development and Collaboration Updates: Sutro plans to submit an IND for STRO-003, a ROR1-targeting ADC, in 2024.Sutro plans to submit an IND for STRO-004, a tissue factor-targeting ADC, in 2025.Sutro continues to seek to maximize the value of its proprietary cell-free platform by working with partners on programs in multiple disease spaces and geographies and has generated from collaborators an aggregate of approximately $854 million in payments through December 31, 2023, including equity investments.In November 2023, Vaxcyte exercised its option to enter into a manufacturing rights agreement with Sutro to obtain control over the development and manufacture of cell-free extract for use under its license agreement with Sutro, including for Vaxcyte’s pneumococcal conjugate vaccine (PCV) franchise, which includes VAX-24 and VAX-31. Upon exercising the option, Vaxcyte paid Sutro $50 million and is obligated to pay Sutro an additional $25 million within six months. Upon the occurrence of certain regulatory milestones, Vaxcyte would be obligated to pay Sutro up to an additional $60 million. Corporate Updates: Sutro continues to build a world-class leadership team through the promotion of Jane Chung to President and Chief Operating Officer, a newly created role in which she will be responsible for driving operational excellence, strategic growth, and overall business success at Sutro. Full Year 2023 Financial Highlights Cash, Cash Equivalents and Marketable SecuritiesAs of December 31, 2023, Sutro had cash, cash equivalents and marketable securities of $333.7 million, as compared to $321.1 million as of September 30, 2023, and approximately 0.7 million shares of Vaxcyte common stock with a fair value of $41.9 million, which together provide a projected cash runway into the second half of 2025, based on current business plans and assumptions. Current market conditions provide a challenging financing environment. In this context, Sutro is continuing its process of evaluating its programs and spending. Unrealized Gain from Increase in Value of Vaxcyte Common Stock The non-operating, unrealized gain of $9.9 million for the year 2023 was due to the increase since December 31, 2022 in the estimated fair value of Sutro’s holdings of Vaxcyte common stock. Vaxcyte common stock held by Sutro will be remeasured at fair value based on the closing price of Vaxcyte’s common stock on the last trading day of each reporting period, with any non-operating, unrealized gains and losses recorded in Sutro’s statements of operations. Revenue Revenue was $153.7 million for the year ended December 31, 2023, as compared to $67.8 million for the same period in 2022, with the 2023 amount related principally to the Vaxcyte manufacturing rights agreement option exercise, Astellas and Merck collaborations, and the recognition of a contingent payment from Tasly. Future collaboration and license revenue under existing agreements, and from any additional collaboration and license partners, will fluctuate as a result of the amount and timing of revenue recognition of upfront, milestones, and other agreement payments. Operating Expenses Total operating expenses for the year ended December 31, 2023 were $243.0 million, as compared to $196.7 million for the same period in 2022. The year 2023 includes non-cash expenses for stock-based compensation of $24.9 million and depreciation and amortization of $6.8 million, as compared to $26.3 million and $5.7 million, respectively, in the comparable 2022 period. Total operating expenses for the year ended December 31, 2023 were comprised of research and development expenses of $180.4 million and general and administrative expenses of $62.6 million. About Sutro Biopharma Sutro Biopharma, Inc., is a clinical-stage company relentlessly focused on the discovery and development of precisely designed cancer therapeutics, to transform what science can do for patients. Sutro’s fit-for-purpose technology, including cell-free XpressCF®, provides the opportunity for broader patient benefit and an improved patient experience. Sutro has multiple clinical stage candidates, including luveltamab tazevibulin, or luvelta, a registrational-stage folate receptor alpha (FolRα)-targeting ADC in clinical studies. A robust pipeline, coupled with high-value collaborations and industry partnerships, validates Sutro’s continuous product innovation. Sutro is headquartered in South San Francisco. For more information, follow Sutro on social media @Sutrobio, or visit www.sutrobio.com. Forward-Looking Statements This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, anticipated preclinical and clinical development activities, including enrollment and site activation; timing of announcements of clinical results, trial initiation, and regulatory filings; outcome of regulatory decisions; potential benefits of luvelta and the Company’s other product candidates and platform; potential expansion into other indications and combinations, including the timing and development activities related to such expansion; potential market opportunities for luvelta and the Company’s other product candidates; and the Company’s expected cash runway;. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Although the Company believes that the expectations reflected in such forward-looking statements are reasonable, the Company cannot guarantee future events, results, actions, levels of activity, performance or achievements, and the timing and results of biotechnology development and potential regulatory approval is inherently uncertain. Forward-looking statements are subject to risks and uncertainties that may cause the Company’s actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to the Company’s ability to advance its product candidates, the receipt and timing of potential regulatory designations, approvals and commercialization of product candidates and the Company’s ability to successfully leverage Fast Track designation, the market size for the Company’s product candidates to be smaller than anticipated, clinical trial sites, supply chain and manufacturing facilities, the Company’s ability to maintain and recognize the benefits of certain designations received by product candidates, the timing and results of preclinical and clinical trials, the Company’s ability to fund development activities and achieve development goals, the Company’s ability to protect intellectual property, the value of the Company’s holdings of Vaxcyte common stock, and the Company’s commercial collaborations with third parties and other risks and uncertainties described under the heading “Risk Factors” in documents the Company files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this press release, and the Company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof. ContactEmily WhiteSutro Biopharma (650) 823-7681 ewhite@sutrobio.com Sutro Biopharma, Inc.Selected Statements of Operations Financial Data(Unaudited)(In thousands, except share and per share amounts) For the year ended December 31 2023 2022 2021 Revenues$153,731 $67,772 $61,880 Operating expenses Research and development 180,425 137,171 104,400 General and administrative 62,584 59,544 56,004 Total operating expenses 243,009 196,715 160,404 Loss from operations (89,278) (128,943) (98,524)Interest income 14,510 3,455 577 Unrealized gain (loss) on equity securities 9,917 12,130 (4,454)Non-cash interest expense related to the sale of future royalties (12,570) - - Interest and other income (expense), net (11,180) (3,346) (3,137)Loss before provision for income taxes (88,601) (116,704) (105,538)Provision for income taxes 18,192 2,500 - Net loss$(106,793) $(119,204) $(105,538)Net loss per share, basic and diluted$(1.78) $(2.35) $(2.29)Weighted-average shares used in computing basic and diluted loss per share 60,163,542 50,739,185 46,119,089 Sutro Biopharma, Inc.Selected Balance Sheets Financial Data(Unaudited)(In thousands) December 31, 2023(1) 2022(2) Assets Cash, cash equivalents and marketable securities$333,681 $302,344 Investment in equity securities 41,937 32,020 Accounts receivable 36,078 7,122 Property and equipment, net 21,940 24,621 Operating lease right-of-use assets 22,815 26,443 Other assets 14,285 14,394 Total Assets$470,736 $406,944 Liabilities and Stockholders’ Equity Accounts payable, accrued expenses and other liabilities$64,293 $32,822 Deferred revenue 74,045 106,644 Operating lease liability 29,574 34,159 Debt 4,061 16,271 Deferred royalty obligation related to the sale of future royalties 149,114 - Total liabilities 321,087 189,896 Total stockholders’ equity 149,649 217,048 Total Liabilities and Stockholders’ Equity$470,736 $406,944 (1)The condensed balance sheet as of December 31, 2023 was derived from the unaudited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023, filed with the Securities and Exchange Commission on March 25, 2024.(2)The condensed balance sheet as of December 31, 2022 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2022, filed with the Securities and Exchange Commission on March 30, 2023.