– Company announces U.S. FDA clearance of Investigational New Drug (IND) application for STRO-004, its potential best-in-class Tissue Factor ADC; Expects to dose first patient before year-end –

– 公司宣布其潜在的同类最佳组织因子ADC药物STRO-004获得美国FDA的临床试验新药（IND）申请批准；预计在今年年底前为首位患者给药 –

– Company presented new preclinical data at World ADC and SITC,

– 公司在世界ADC和SITC上展示了新的临床前数据，

highlighting novel dual-payload ADCs designed to overcome resistance and delay progression –

突出显示设计用于克服耐药性和延缓疾病进展的新型双载荷ADC——

– Company to host a virtual R&D Day on Wednesday, November 12, 2025 at 10:00AM ET –

– 公司将于2025年11月12日星期三东部时间上午10:00举办虚拟研发日活动 –

– Cash, cash equivalents and marketable securities as of September 30, 2025 of $167.6 million, with cash runway into at least mid-2027, including certain expected near-term milestone payments –

截至2025年9月30日，现金、现金等价物和可出售证券为1.676亿美元，包括某些预期的近期里程碑付款，现金跑道至少延续至2027年年中。

SOUTH SAN FRANCISCO, Calif., Nov. 06, 2025 (GLOBE NEWSWIRE) -- Sutro Biopharma, Inc. (Sutro or the Company) (NASDAQ: STRO), an oncology company pioneering site-specific and novel-format antibody drug conjugates (ADCs), today reported its financial results for the third quarter of 2025 and recent business highlights..

加利福尼亚州南旧金山，2025年11月6日（环球新闻社）——Sutro Biopharma, Inc.（Sutro或公司）（纳斯达克股票代码：STRO），一家致力于位点特异性和新型抗体药物偶联物（ADC）的肿瘤学公司，今日公布了其2025年第三季度的财务业绩及近期业务亮点。

“We’ve made strong progress this quarter as we continue to build momentum across our next-generation ADC portfolio,” said Jane Chung, Sutro’s Chief Executive Officer. “STRO-004, our Tissue Factor ADC, has received IND clearance ahead of our projections and remains on track to enter the clinic this year, backed by compelling preclinical data that highlight its strong safety profile and potential best-in-class differentiation.

“我们在本季度取得了强劲的进展，因为我们继续在下一代ADC产品组合中建立动力，”Sutro首席执行官Jane Chung表示。“STRO-004，我们的组织因子ADC，已经获得了IND批准，早于我们的预期，并且仍然按计划在今年进入临床阶段，背后有令人信服的临床前数据支持，突显了其强大的安全性以及潜在的同类最佳差异化优势。”

In parallel, we’re strengthening our leadership in dual-payload ADCs by showcasing positive new preclinical data from our wholly owned programs and advancing our collaboration with Astellas. This collaboration focuses on developing dual-payload ADCs that combine a cytotoxic payload with a novel immunostimulatory payload, designed to enhance the therapeutic index and overcome tumor resistance.

同时，我们正通过展示自有项目的积极新临床前数据，以及推进与安斯泰来（Astellas）的合作，加强我们在双载荷抗体药物偶联物（ADC）领域的领导地位。该合作专注于开发结合细胞毒性载荷与新型免疫刺激载荷的双载荷ADC，旨在提高治疗指数并克服肿瘤耐药性。

We look forward to sharing updates on each of our next-generation ADC programs at our virtual R&D Day on November 12.”.

我们期待在11月12日的虚拟研发日上分享我们每个下一代ADC项目的最新进展。

Ms. Chung continued: “Following our recent organizational restructuring, we are well positioned to focus resources on the programs and partnerships that offer the greatest potential for near-term value creation. The resulting operational efficiencies, combined with expected near-term milestone payments, extend our cash runway into at least mid-2027—allowing us to advance key programs through meaningful clinical milestones.

钟女士继续说道：“在我们最近的组织架构重组之后，我们已经做好了充分准备，将资源集中在那些具有最大近期价值创造潜力的项目和合作伙伴关系上。由此产生的运营效率，加上预期的近期里程碑付款，使我们的现金跑道至少延长至2027年年中——这让我们能够推动关键项目通过重要的临床里程碑。”

With a sharpened strategic focus and a robust scientific foundation, we believe Sutro is poised to deliver differentiated best-in-class ADCs that have the potential to redefine standards of care in oncology.”.

“凭借更加明确的战略重点和强大的科学基础，我们相信Sutro有望推出具有差异化优势的同类最佳ADC，这些ADC有潜力重新定义肿瘤学的治疗标准。”

Wholly Owned Pipeline

全资拥有的管道

STRO-004:

STRO-004:

The Company received U.S. FDA clearance of its IND application for STRO-004, its potential best-in-class Tissue Factor ADC. Sutro remains on track to dose the first patient in the first-in-human basket trial with STRO-004 before year-end. STRO-004 has a favorable preclinical safety profile in non-human primate studies up to 50 mg/kg, the highest dose tested..

公司已收到美国FDA对其潜在同类最佳组织因子ADC药物STRO-004的IND申请的批准。Sutro仍然有望在年底前为首位患者在STRO-004的首次人体篮式试验中给药。在非人类灵长类动物研究中，STRO-004在高达50 mg/kg的剂量下具有良好的临床前安全性，这是测试的最高剂量。

STRO-006:

STRO-006:

A highly selective integrin β6 (ITGB6) ADC, STRO-006 is expected to enter clinical development in 2026 for the treatment of multiple solid tumors.

一种高选择性的整合素β6（ITGB6）抗体药物偶联物（ADC），STRO-006预计将于2026年进入临床开发，用于治疗多种实体瘤。

Dual-Payload Program:

双有效载荷程序：

Sutro’s wholly owned dual-payload ADC program remains on track, with an IND submission targeted for 2027.

Sutro全资拥有的双载荷ADC项目仍在按计划进行，预计将于2027年提交IND。

Next-Generation ADC Collaborations

下一代ADC合作

Astellas:

安斯泰来：

Two research and development programs are progressing under Sutro’s collaboration with Astellas focused on dual-payload immunostimulatory ADCs (iADCs), including one program that entered an IND-enabling toxicology study in the first quarter of 2025.

在Sutro与Astellas合作的框架下，两个研发项目正在推进，专注于双载荷免疫刺激抗体药物偶联物（iADCs），其中一个项目已于2025年第一季度进入IND前毒理学研究阶段。

Industry/Medical Conferences

行业/医学会议

Upcoming Investor Conferences

即将举行的投资者会议

Management will participate in the following upcoming healthcare investor conference. A webcast of the presentation will be accessible through the News & Events page of the Investor Relations section of the Company’s website at www.sutrobio.com. An archived replay will be available for at least 30 days after the event..

管理层将参与以下即将举行的医疗保健投资者会议。演讲的网络直播可通过公司网站 www.sutrobio.com 上投资者关系部分的新闻与活动页面访问。活动结束后，存档的重播将至少提供30天。

Corporate Updates

公司动态

Third Quarter 2025 Financial Highlights

2025年第三季度财务亮点

Cash, Cash Equivalents and Marketable Securities

现金、现金等价物和可出售证券

As of September 30, 2025, Sutro had cash, cash equivalents and marketable securities of $167.6 million, as compared to $388.3 million as of September 30, 2024. Cost reductions subsequently realized from the restructuring, combined with refocused clinical development priorities and certain expected near-term milestone payments give the Company an expected cash runway into at least mid-2027..

截至2025年9月30日，Sutro拥有现金、现金等价物和可售证券1.676亿美元，而截至2024年9月30日为3.883亿美元。随后通过重组实现的成本削减，加上重新聚焦的临床开发重点及某些预期的近期里程碑付款，使公司预计的现金流可支撑至至少2027年年中。

Revenue

收入

Revenue was $9.7 million for the quarter ended September 30, 2025, as compared to $8.5 million for the quarter ended September 30, 2024, with the 2025 amount related principally to the Astellas collaboration. 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..

截至2025年9月30日的季度收入为970万美元，而截至2024年9月30日的季度收入为850万美元，其中2025年的金额主要与Astellas的合作相关。根据现有协议以及任何额外合作和许可伙伴，未来合作和许可收入将因预付款、里程碑付款及其他协议付款的金额和确认时间而有所波动。

Research & Development (R&D) and General & Administrative (G&A) Expenses

研发（R&D）费用和一般及行政（G&A）费用

Total R&D and G&A expenses for the quarter ended September 30, 2025 were $48.6 million, as compared to $76.4 million for the quarter ended September 30, 2024. The 2025 quarter includes non-cash expenses for stock-based compensation of $1.9 million and depreciation and amortization of $1.9 million, as compared to $6.5 million and $1.8 million, respectively, in the comparable 2024 period..

截至2025年9月30日的季度，研发和管理费用总计为4860万美元，而截至2024年9月30日的季度为7640万美元。2025年第三季度包含190万美元的非现金股份薪酬支出以及190万美元的折旧和摊销费用，而2024年同期分别为650万美元和180万美元。

Restructuring Costs

重组成本

The total cash payments and costs related to the further operational restructuring announced on September 29, 2025 are estimated to be approximately $4.1 million to $4.3 million, with a significant majority of these amounts expected to be paid in the fourth quarter of 2025. These estimates are subject to a number of assumptions and actual results may differ.

2025年9月29日宣布的进一步运营重组相关的总现金支付和成本预计约为410万美元至430万美元，其中很大一部分金额预计将在2025年第四季度支付。这些估计基于多种假设，实际结果可能会有所不同。

The Company may also incur additional costs not currently contemplated due to events that may occur as a result of, or that are associated with, the corporate restructuring..

公司还可能因与公司重组相关或由此产生的事件而产生目前未预料到的额外成本。

About Sutro Biopharma

关于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.

Sutro Biopharma, Inc. 正在推进一个下一代抗体药物偶联物 (ADC) 平台，该平台旨在提供单载荷和双载荷的 ADC，为癌症患者带来有意义的突破。通过全面优化抗体、连接子和载荷，Sutro 的无细胞平台生产的 ADC 旨在改善药物暴露、减少副作用，并扩大可治疗的肿瘤类型范围。

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..

凭借在双载荷ADC领域的独特能力，Sutro旨在克服治疗耐药性，并重新定义癌症治疗的可能性。公司单载荷和双载荷ADC的研发管线针对治疗选择有限且对改进疗法需求显著的大型肿瘤市场。

For more information, follow Sutro on social media @Sutrobio or visit

欲了解更多信息，请在社交媒体上关注 Sutro @Sutrobio 或访问

www.sutrobio.com

www.sutrobio.com

.

。

Forward-Looking Statements

前瞻性声明

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, trial initiation, clinical results, and other regulatory filings; outcome of discussions with regulatory authorities; potential benefits of the Company’s product candidates and platform; potential business development and partnering transactions; potential market opportunities for the Company’s product candidates; the timing and receipt of anticipated future milestone payments; the Company’s expected cash runway; and  the expected costs and cost reductions associated with the restructuring.

本新闻稿包含1995年《私人证券诉讼改革法案》“安全港”条款所指的前瞻性陈述，包括但不限于预期的临床前和临床开发活动；IND提交、试验启动、临床结果及其他监管文件的时间安排；与监管机构讨论的结果；公司候选产品和平台的潜在益处；潜在的业务发展和合作伙伴交易；公司候选产品的潜在市场机会；预期未来里程碑付款的时间和收讫；公司的预期现金跑道；以及与重组相关的预期成本和成本削减。

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.

所有非历史事实的陈述均可能被视为前瞻性陈述。尽管公司认为这些前瞻性陈述中反映的预期是合理的，但公司无法保证未来事件、结果、行动、活动水平、表现或成就，且生物技术开发和潜在监管批准的时间与结果本质上存在不确定性。

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 m.

前瞻性声明受到风险和不确定性的约束，可能导致公司的实际活动或结果与任何前瞻性声明中表达的内容存在显著差异，包括与公司推进其产品候选者能力相关的风险和不确定性、潜在监管认定、批准和产品候选者商业化的时机、公司产品候选者的市场规模小于预期、临床试验地点、供应链和制造相关风险。

Investor Contact

投资者联系人

Emily White

艾米丽·怀特

Sutro Biopharma

苏特罗生物制药

(650) 823-7681

(650) 823-7681

ewhite@sutrobio.com

ewhite@sutrobio.com

Media Contact

媒体联系人

Amy Bonanno

艾米·博纳诺

Lyra Strategic Advisory

拉伊拉战略咨询公司

abonanno@lyraadvisory.com

abonanno@lyraadvisory.com

Sutro Biopharma, Inc.

Sutro生物制药公司

Selected Statements of Operations Financial Data

已选财务数据的损益表

(Unaudited)

（未经审计）

(In thousands, except share and per share amounts)

（单位：千，股份和每股金额除外）

Sutro Biopharma, Inc.

Sutro生物制药公司

Selected Balance Sheets Financial Data

选定的资产负债表财务数据

(Unaudited)

（未经审计）

(In thousands)

（单位：千）

(1)

(1)

The condensed balance sheet as of September 30, 2025 was derived from the unaudited financial statements included in the Company's Quarterly Report on Form 10-Q for the quarter ended September 30, 2025, filed with the Securities and Exchange Commission on November 6, 2025.

截至2025年9月30日的简明资产负债表源自公司于2025年11月6日向证券交易委员会提交的截至2025年9月30日的季度10-Q表季度报告中包含的未经审计财务报表。

(2)

(2)

The condensed balance sheet as of December 31, 2024 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2024, filed with the Securities and Exchange Commission on March 13, 2025.

截至2024年12月31日的简明资产负债表源自公司于2025年3月13日向证券交易委员会提交的截至2024年12月31日年度的10-K表格年报中的经审计财务报表。

Released November 6, 2025

发布于2025年11月6日