Sutro Biopharma posts early STRO-004 responses, updates Q2 2026 financials

Sutro Biopharma released second quarter 2026 results on August 12, 2026, alongside an early look at its Phase 1 study of STRO-004, a Tissue Factor-targeting ADC using a DAR8 exatecan payload. The company described a favorable tolerability profile along with early signals of clinical activity in heavily pretreated patients with advanced solid tumors.¹

CEO Jane Chung said the initial dose escalation cohorts were enrolled within seven months and the company is now working to optimize the go-forward dose.¹

As of a July 24, 2026 data cutoff, the trial recorded several responses, including both confirmed and unconfirmed partial responses that were still ongoing, spanning three tumor types among patients evaluable by RECIST criteria, with responses noted in pancreatic cancer, head and neck cancer, and non-small cell lung cancer at dose levels of 3 to 4 mg/kg.¹ The overall rate of discontinuation due to adverse events was 6%.¹ Dose optimization is continuing between 4 and 5 mg/kg, and a maximum tolerated dose has not yet been established.¹ The company plans its next STRIVE-01 update for the first half of 2027, when expansion cohorts are also expected to begin.¹

On the pipeline side, Sutro expects to start a Phase 1 trial of STRO-006, an ITGB6-targeting ADC, in the third quarter of 2026.¹ STRO-227, a dual-payload ADC targeting PTK7, remains on track for an IND submission in 2026.¹

Financially, Sutro held $164.3 million in cash, cash equivalents and marketable securities as of June 30, 2026, down from $202.6 million at the end of the first quarter.¹ The company said this balance is expected to support operations into at least the second quarter of 2028.¹ Quarterly revenue was $9.8 million, compared with $63.7 million a year earlier, reflecting the Astellas collaboration.¹ Combined R&D and G&A expenses totaled $39.5 million, down from $48.7 million in the same quarter of 2025.¹