Sutro Biopharma Announces Additional Data for Dose-Escalation Phase 1 Study of STRO-002 to be Presented at ASCO 2021
SOUTH SAN FRANCISCO, Calif., May 19, 2021 /PRNewswire/ -- Sutro Biopharma, Inc., (NASDAQ: STRO), a clinical-stage drug discovery, development and manufacturing company focused on the application of precise protein engineering and rational design to create next-generation cancer and autoimmune therapeutics, today announced additional data from the Company's dose-escalation cohort of the Phase 1 study of STRO-002, a folate receptor alpha (FolRα) targeting antibody-drug conjugate (ADC) for patients with advanced, progressive ovarian cancer; the data will also be presented as a poster at the American Society of Clinical Oncology (ASCO) 2021 Annual Meeting to be held on June 4-8, 2021.
"We are pleased to share today the maturing dose-escalation data on STRO-002 that will be presented by principal investigator Dr. R. Wendel Naumann during the 2021 ASCO Annual Meeting," said Bill Newell, Chief Executive Officer of Sutro Biopharma. "The 39 patients with advanced, progressive ovarian cancer on the study achieved a median progression-free survival of 7.2 months. Median duration of response was 5.8 months in the five confirmed responders. The dose-escalation data positions STRO-002 as a potentially important treatment option providing durable clinical benefit, especially when compared to standard of care and other agents in clinical development."
Summary of STRO-002-GM1 Phase 1 Dose-Escalation Cohort Update
The cohort enrolled 39 patients and included 34 patients treated with clinically active dose levels at 2.9 mg/kg or higher, of which 31 patients had at least one post-baseline scan and were evaluable for RECIST responses. The cohort completed enrollment in August 2020 and the data in the ASCO 2021 abstract was based on an earlier cut-off date of January 30, 2021. The data that will be presented in a poster at ASCO 2021 had a cut-off date of April 23, 2021 and is summarized below.
Tissue samples for FolRα-expression analysis were provided by clinical sites retrospectively and were available in 18 patients treated at ≥ 2.9 mg/kg in the dose-escalation cohort. Antitumor activity was observed across a broad range of FolRα-expression levels.
Dr. Arturo Molina, Chief Medical Officer of Sutro commented, "It is encouraging to see the durable clinical benefit in our dose-escalation cohort, including in patients with lower levels of FolRα-expression who are being excluded from other ovarian cancer clinical trials. The need for new treatment options for this community drives our efforts to potentially bring STRO-002 to the broadest patient population that may benefit from the therapy. In consideration of a potential FolRα biomarker enrichment strategy, we plan to take a data-driven approach through balancing an efficient path forward, while serving the high unmet medical needs for ovarian cancer patients."
The Phase 1 dose-escalation data with a data cut-off date of April 23, 2021 will be available today as part of the Company's Corporate Presentation, which can be accessed through the Company's website at www.sutrobio.com. Additionally, the data will be presented virtually as a poster at the 2021 ASCO Annual Meeting from June 4-8, 2021, with details as follows:
About the STRO-002-GM1 Phase 1 Study
About Sutro Biopharma
Sutro's proprietary and integrated cell-free protein synthesis platform XpressCF® and site-specific conjugation platform XpressCF+™ led to the discovery of STRO-001 and STRO-002, Sutro's first two internally-developed ADCs. STRO-001 is a CD74-targeting ADC currently being investigated in a Phase 1 clinical trial of patients with advanced B-cell malignancies, including multiple myeloma and non-Hodgkin lymphoma. STRO-001 was granted Orphan Drug Designation by the FDA for multiple myeloma in October 2018. STRO-002 is a folate receptor alpha (FolRα)-targeting ADC, currently being investigated in a Phase 1 clinical trial of patients with ovarian and endometrial cancers. A third product candidate, CC-99712 (BCMA-targeting ADC), which is part of Sutro's collaboration with Bristol Myers Squibb (formerly Celgene Corporation), is enrolling patients for its Phase 1 clinical trial of patients with multiple myeloma and has received Orphan Drug Designation from the FDA for multiple myeloma. A fourth product candidate, M1231, (MUC1-EGFR, first-in-class bispecific ADC), which is part of Sutro's collaboration with Merck KGaA, EMD Serono (EMD Serono) is enrolling patients for its Phase 1 clinical trial of patients with metastatic solid tumors, non-small cell lung cancer (NSCLC) and esophageal squamous cell carcinoma. The four product candidates above being evaluated in clinical trials resulted from Sutro's XpressCF® and XpressCF+™ technology platforms. Bristol Myers Squibb and EMD Serono have worldwide development and commercialization rights for CC-99712 and M1231, respectively, for which Sutro is entitled to milestone or contingent payments and tiered royalties.
Sutro is dedicated to transforming the lives of cancer patients by creating medicines with improved therapeutic profiles for areas of unmet need. To date, Sutro's platform has led to cytokine-based immuno-oncology therapies, ADCs, vaccines and bispecific antibodies directed at precedented targets in clinical indications where the current standard of care is suboptimal.
The platform allows it to accelerate discovery and development of potential first-in-class and best-in-class molecules through rapid and systematic evaluation of protein structure-activity relationships to create optimized homogeneous product candidates.
In addition to developing its own oncology pipeline, Sutro is collaborating with select pharmaceutical and biotech companies to discover and develop novel, next-generation therapeutics. As the pace of clinical development accelerates, Sutro and its partners are developing therapeutics designed to more efficiently kill tumors without harming healthy cells.
SOURCE Sutro Biopharma
Company Codes: NASDAQ-NMS:STRO