Sutro Biopharma Announces Participation at the 16th Annual World ADC Conference

Sutro Biopharma, Inc. (Sutro or the Company) (NASDAQ: STRO), an oncology company pioneering site-specific and novel-format antibody drug conjugates (ADCs), today announced its participation at the 16th Annual World ADC Conference, taking place in San Diego, November 3-6, 2025.

“We look forward to presenting new preclinical data at this year’s World ADC conference that underscore the breadth of innovation emerging from Sutro’s platform and the meaningful progress we’re making toward advancing the next-generation of ADCs,” said Hans-Peter Gerber, Sutro’s Chief Scientific Officer. “Among the highlights, we’re excited to share results demonstrating how our dual-payload ADCs, including immunostimulatory ADCs, can potentially redefine treatment paradigms by enhancing therapeutic index and addressing tumor resistance—two of the biggest challenges in oncology today. Together with our unique cell-free platform, these advances reinforce Sutro’s leadership in ADC innovation and our commitment to driving long-term value through transformative science.”

Presentation/Panel Discussion Details:

Showcasing Development of Site-Specific, High-DAR Dual-Payload ADCs Presenter: Daniel Calerese, Ph.D.

Date/Time: November 3, 2025, 12:00PM PT

Developing Next-Generation Immunostimulatory Dual Payload ADCs to Enhance Therapeutic Index & Tackle Patient Resistance Presenter: Gang Yin, Ph.D.

Date/Time: November 3, 2025, 12:30PM PT

Exploring Supply Chain & CMC Advantages of Cell-Free Antibody Manufacturing to Design & Produce Unique ADCs Presenter: Venkatesh Srinivasan, Ph.D.

Date/Time: November 4, 2025, 11:00AM PT

Panel Discussion: Delving into Novel Design & Development to Strive for Next-Generation ADCs Providing Long-Term Benefit to Patients Sutro Participant: Hans-Peter Gerber, Ph.D.

Date/Time: November 4, 2025, 5:00PM PT

Developing Site-Specific Dual Payload ADCs Featuring Novel Linker Payloads to Overcome Resistance Mechanisms Presenter: Krishna Bajjuri, Ph.D.

Date/Time: November 5, 2025, 11:00AM PT

Panel Discussion: The Way Forward: What’s the New Path to the Next-Generation of ADCs? Sutro Participant: Daniel Calarese, Ph.D.

Date/Time: November 5, 2025, 12:30PM PT

Laying Out Discovery & Development of STRO-006: A Differentiated Topo1-ADC Targeting Integrin Beta-6 Presenter: Alice Yam, Ph.D.

Date/Time: November 5, 2025, 2:00PM PT

Summary Panel Discussion: What is Showing the Most Promise & What Still Needs to be Proven in ADC Chemistry Innovation? Sutro Participant: Hans-Peter Gerber, Ph.D.

Date/Time: November 5, 2025, 3:00PM PT

Following the event, the content will be made available in the Clinical/Scientific Presentation and Publication Highlights section of Sutro Biopharma’s website at www.sutrobio.com .

About Sutro Biopharma Sutro Biopharma, Inc. is advancing a next-generation antibody-drug conjugate (ADC) platform designed to deliver single- and dual-payload ADCs that enable meaningful breakthroughs for patients with cancer. By fully optimizing the antibody, linker, and payload, Sutro’s cell-free platform produces ADCs that are engineered to improve drug exposure, reduce side effects, and expand the range of treatable tumor types. With unique capabilities in dual-payload ADCs, Sutro aims to overcome treatment resistance and redefine what’s possible in cancer therapy. The Company’s pipeline of single- and dual-payload ADCs targets large oncology markets with limited treatment options and significant need for improved therapies.

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; timing of announcements of IND submissions, clinical results, trial initiation, and other regulatory filings; outcome of discussions with regulatory authorities; potential benefits of the Company’s product candidates and platform; and potential market opportunities for the Company’s product candidates; . 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, 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 obtain, 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, 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 Data

Investor Contact Emily White Sutro Biopharma (650) 823-7681 Media Contact Amy Bonanno Lyra Strategic Advisory