--- title: "Sutro Biopharma plans to cut workforce by about one-third" url: "https://aibio.space/news/sutro-biopharma-plans-cut-workforce-about-one-third-expects-cash/" publisher: "aibio.space (Biotech Investor Relations News)" date: "2025-09-29" section: "Distress" tickers: "NASDAQ:STRO" source: "https://www.sec.gov/Archives/edgar/data/1382101/000119312525223434/stro-20250929.htm" summary: "Sutro Biopharma (Nasdaq: STRO) plans a workforce reduction of approximately one-third to focus on three preclinical ADC programs. It estimates $4.1 million" --- By the aibio.space news desk. Sources - [SUTRO BIOPHARMA, INC. Form 8-K filed September 29, 2025 (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1382101/000119312525223434/stro-20250929.htm) - [SUTRO BIOPHARMA, INC. exhibit stro-ex99_1.htm to the September 29, 2025 Form 8-K (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1382101/000119312525223434/stro-ex99_1.htm) - [SUTRO BIOPHARMA, INC. Form 10-K filed March 13, 2025: business overview and signatures (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1382101/000095017025038884/stro-20241231.htm) [STRO](https://aibio.space/companies/sutro-biopharma/) 2025-09-29 # Sutro Biopharma plans to cut workforce by about one-third, expects cash runway into mid-2027 Tickers [STRO](https://aibio.space/companies/sutro-biopharma/) Sutro Biopharma (Nasdaq: STRO) plans a workforce reduction of approximately one-third to focus on three preclinical ADC programs. It estimates $4.1 million to $4.3 million in costs. ## Key facts - **Company**: Sutro Biopharma, Inc. (NASDAQ: STRO) - **News type**: Distress - **Primary source**: [SUTRO BIOPHARMA, INC. Form 8-K filed September 29, 2025 (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1382101/000119312525223434/stro-20250929.htm) *The Capitol dome against a blue sky. Photo: Carol M Highsmith, CC0, via rawpixel. The picture shows the field, not the companies named.* Sutro Biopharma, Inc. (Nasdaq: [STRO](https://aibio.space/companies/sutro-biopharma/)) announced on September 29, 2025, a restructuring that will cut its workforce by about one-third and focus spending on three preclinical antibody-drug conjugate, or ADC, programs. The company disclosed the plan in a [Form 8-K](https://www.sec.gov/Archives/edgar/data/1382101/000119312525223434/stro-20250929.htm) of the same date, under Item 2.05, which covers costs of exit or disposal activities. The press release attached as Exhibit 99.1 gives the same plan. David Pauling, General Counsel and Chief Administrative Officer, signed the 8-K. The company calls the plan a further organizational restructuring. ## The cuts and the cost The company estimates total cash payments and costs of about $4.1 million to $4.3 million for the reprioritization and the workforce reduction. The 8-K says a significant majority of that will be paid in the fourth quarter of 2025. It also says the estimates rest on assumptions, actual results may differ, and the company may incur costs not currently contemplated. The restructuring is meant to prioritize both the ADC programs and the company's research and development collaborations. The 8-K does not say which employees or functions will be cut, or how many people are employed now. ## The runway claim The company says the restructuring, along with certain expected near-term milestone payments, extends its cash runway into at least mid-2027. That claim has conditions attached. The press release says the runway runs past the planned announcement of initial clinical data from STRO-004, its next-generation Tissue Factor-targeting exatecan ADC, and past the start of clinical studies for at least one of the other ADC programs. The company expects initial clinical data from STRO-004 in 2026. The press release also quotes chief executive Jane Chung: "We remain on track to advance STRO-004 into the clinic this year." STRO-004 was still preclinical in the 2024 annual report, which said the company expected to submit an Investigational New Drug application in the second half of 2025. The 8-K gives no month for the first dosing or the data. The runway also depends on milestone payments the company expects but has not yet received. The 8-K does not identify those payments, their size or their timing. ## Cash before the cuts The company's [annual report for 2024](https://www.sec.gov/Archives/edgar/data/1382101/000095017025038884/stro-20241231.htm) reports cash, cash equivalents and marketable securities of $316.9 million at December 31, 2024, down from $333.7 million at December 31, 2023. Those are the figures for the year before the restructuring, and the annual report does not give a cash figure for mid-2025. The annual report's investment-risk section says the company's investments are held to preserve capital for operations. It does not say how long the cash would last at the 2024 spending rate. ## Collaborations Sutro's technology is an ADC platform built on its XpressCF and XpressCF+ cell-free systems. The 2024 report says the company has partnered its platform with several large drugmakers. Those include an immunostimulatory ADC collaboration with Astellas Pharma Inc., a cytokine derivative collaboration with Merck Sharp & Dohme Corp., a BCMA ADC collaboration with Celgene Corporation, a wholly owned subsidiary of Bristol Myers Squibb Company, and a MUC1-EGFR ADC collaboration with Merck KGaA, which operates in the United States and Canada as EMD Serono. The 8-K does not say whether any of those partners will change the scope of its work, or whether the restructuring affects the collaboration milestones the company expects. ## What comes next The company's stated path is a planned clinical start for STRO-004 in 2025 and initial data in 2026, followed by the start of clinical studies for at least one more ADC program. Its runway estimate of at least mid-2027 rests on those events and on milestone payments not yet received. The 8-K does not give a date for the workforce reduction. [Report an error](https://aibio.space/reputation/#correction) ## Companies in this story STRO Sutro Biopharma, Inc. 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Cite as: aibio.space, "Sutro Biopharma plans to cut workforce by about one-third", 2025-09-29, https://aibio.space/news/sutro-biopharma-plans-cut-workforce-about-one-third-expects-cash/