On November 9, 2024 Sapience Therapeutics, Inc., a clinical-stage biotechnology company focused on the discovery and development of peptide therapeutics to address oncogenic and immune dysregulation that drive cancer, reported the presentation of clinical and non-clinical results on its lead programs, ST101 and ST316, at the Society for Immunotherapy of Cancer (SITC) (Free SITC Whitepaper)’s (SITC) (Free SITC Whitepaper) 39th Annual Meeting, being held November 6-10, 2024, in Houston, TX (Press release, Sapience Therapeutics, NOV 9, 2024, View Source [SID1234648063]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

ST101 is a first-in-class antagonist of C/EBPβ, currently being evaluated in patients with recurrent and newly diagnosed GBM in the Phase 2 portion of a Phase 1-2 clinical study (NCT04478279). ST316 is a first-in-class antagonist of the interaction between β-catenin and its co-activator, BCL9, a complex responsible for driving oncogene expression in multiple cancers where aberrant Wnt/β-catenin pathway signaling is observed and immune-exclusion in the tumor microenvironment. ST316 is being evaluated in colorectal cancer patients in the Phase 2 portion of a Phase 1-2 study (NCT05848739).

Dr. Jim Rotolo, Sapience’s SVP, Research and Translational Sciences, commented, "I am thrilled to have presented new clinical and biomarker data on ST101, which provides further evidence that C/EBPβ is a multi-faceted target for the treatment of newly diagnosed and recurrent GBM. The inclusion of our presentation in SITC (Free SITC Whitepaper)’s press briefing earlier this week, as one of 8 abstracts of the more than 1,500 received, highlights the novelty and importance of the data we are observing in our clinical study. Through our Phase 2 and Window-of-Opportunity studies, ST101 has demonstrated impressive disease control as well as modulation of the tumor immune microenvironment (TIME) from immunosuppressive to immune-active. This TIME shift is highly compelling given the immunosuppressive environment that is known to limit the efficacy of immune-oncology (I/O) agents in the treatment of GBM."

Dr. Rotolo continued, "We also presented initial clinical pharmacodynamic data from our ST316 Phase 1 study, demonstrating that ST316 dramatically depletes immunosuppressive cells from peripheral blood of patients. In non-clinical studies, we were pleased to see that treatment with ST316 and PD-1 checkpoint inhibitors had positive effects on tumor outcomes and immune activation. These results at SITC (Free SITC Whitepaper), coupled with the data we have from the Phase 1 study, provide further validation that ST316 has the potential to improve existing I/O approaches."

ST101 Oral Presentation Highlights Include:

Title: "ST101, an inhibitor of the transcription factor C/EBPβ, promotes an immune-active tumor microenvironment in a window of opportunity (WoO) study of patients with glioblastoma (GBM)"
Abstract #: 991
Session Title: Biotech Breakthroughs – Solid Tumor IO at the Tipping Point
Date/Time: Friday, November 8, 2024, 1:45 pm – 3:20 pm CST
Session Location: George R. Brown Convention Center, Level 3 – Grand Ballroom B
Presenting Author: Jim Rotolo, Ph.D., SVP, Research & Translational Sciences, Sapience Therapeutics

C/EBPβ activity within tumors promotes GBM growth, chemo-resistance, EMT, and invasion.
C/EBPβ activity in immune cells promotes an immuno-suppressive environment.
ST101, a C/EBPβ antagonist, has demonstrated safety and proof-of-concept activity in a Phase 2 clinical study, showing that treatment with ST101 leads to impaired tumor growth and increased immune activity.
ST101 Window-of-Opportunity study in Newly Diagnosed GBM cohort (n=9, with 8 evaluable):
87.5% post-surgery disease control rate (DCR), with one complete response (CR) and six stable diseases (SD) as of the data cutoff date
8/9 patients are alive as of the data cutoff date (11-76 weeks)
7/9 patients remain on study with median treatment duration of 9.5 months, with 3 patients remaining on the study for greater than 17 months
ST101 Window-of-Opportunity study in Recurrent GBM cohort (n=9):
4/9 (44%) patients had disease control, with 2 PRs and 2 SDs
Window-of-Opportunity biomarker results demonstrate:
ST101 uptake past the blood-brain barrier (BBB) and into the tumor
Disruption of target C/EBPβ
Shift in TIME from immunosuppressive to immune-active
These data support the combination of ST101 with checkpoint inhibitors as a potential treatment for patients with GBM.
ST101 Poster:

Title: "ST101, an inhibitor of the transcription factor C/EBPß, promotes an immune-active tumor microenvironment in a window of opportunity (WoO) study of patients with glioblastoma (GBM)"
Abstract #: 991
Session: Poster Hall
Date/Time:

Friday, November 8, 2024: 9:00 am – 7:00 pm CST
Session Location: George R. Brown Convention Center, Level 1 – Exhibit Halls AB

ST316 Poster Presentation Details:

Title: "ST316, a peptide antagonist of β-Catenin, depletes immunosuppressive myeloid cell populations and enhances anti-cancer immune responses in in vivo tumor models and in patients"
Abstract #: 1451
Session: Poster Hall
Date/Time:

Friday, November 8, 2024, 9:00 am – 7:00 pm CST
Session Location: George R. Brown Convention Center, Level 1 – Exhibit Halls AB
Presenting Author: Claudio Scuoppo, Ph.D., Principal Scientist, Sapience Therapeutics

ST316 disrupts β-catenin-driven immune-exclusion, promoting a shift to an immune-active TIME via depletion of immunosuppressive MDSCs and TAMs, resulting in enhanced cytotoxic T cell activity.
In the clinic, ST316 depletes highly immunosuppressive PMN-MDSCs in Phase I patients.
In human PBMCs, ST316 induces a dose-dependent decrease in immunosuppressive M2 macrophages and a concomitant increase in M1 proinflammatory macrophages, resulting in increased T cell activation.
In murine tumor models, ST316 inhibition of tumor growth is accompanied by a reduction in MDSC population and repolarization of TAMs to an M1-like phenotype.
In murine tumor models, anti-tumor activity of anti-PD-1 treatment is significantly enhanced by combination with ST316, an event accompanied by a reduction of M2-TAMs.
These data provide support for the advancement ST316 through the current Phase 2 study and in combination with existing immune-oncology approaches to improve responses.
About ST101
ST101, a first-in-class antagonist of C/EBPβ, has completed the main portion of a Phase 2 dose expansion study in recurrent GBM (rGBM) (NCT04478279). An ongoing window-of-opportunity sub-study is evaluating ST101 as a monotherapy in patients with rGBM and in combination with radiation and temozolomide in patients with newly diagnosed GBM (ndGBM), with patients receiving ST101 before and after surgical resection in both cohorts. ST101 has been granted Fast Track designation for rGBM from the U.S. FDA and orphan designations for glioma from the U.S. FDA and the European Commission.

About ST316
ST316 is a first-in-class peptide antagonist of the interaction between β-catenin and its co-activator, BCL9, a complex responsible for driving oncogene expression in multiple cancers where aberrant Wnt/β-catenin pathway signaling is observed. ST316 is being evaluated in the Phase 2 portion of a Phase 1-2 dose-escalation and expansion study (NCT05848739). The Phase 1 portion completed enrollment in July 2024. In the Phase 2 dose expansion, ST316 is being tested in colorectal cancer patients in combination with relevant standards of care and in multiple lines of treatment. Sapience is conducting the Phase 2 study across several sites in the United States.