On April 17, 2026 Ensem Therapeutics, Inc. (ENSEM), a clinical-stage, oncology-focused biopharmaceutical company, reported presentations of preclinical data at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting, being held April 17–22 in San Diego, CA. The data support the differentiated preclinical profiles of ETX-929, a pan-KRAS inhibitor for the treatment of KRAS-altered solid tumors, and ETX-880, a covalent WRN inhibitor for the treatment of microsatellite instability-high (MSI-H) solid tumors.
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!
"These AACR (Free AACR Whitepaper) presentations underscore the breadth and depth of ENSEM’s oncology pipeline, fueled by our proprietary Kinetic Ensemble platform," said Shengfang Jin, PhD, Co-Founder, President, and Chief Executive Officer of ENSEM. "With ETX-929 and ETX-880, we are advancing potential best-in-class small molecule inhibitors against two of the most compelling targets in oncology today—KRAS and WRN. These programs, alongside our clinical-stage PI3Kα program ETX-636, demonstrate the power of our platform to systematically tackle high-value, difficult-to-drug targets with differentiated molecules."
AACR Presentation Details
Details of the presentations are as follows:
ETX-929 (Pan-KRAS Inhibitor)
Title: ETX-929, a potential best-In-class, oral, highly potent and selective dual ON / OFF state Pan-KRAS small molecule inhibitor for the treatment of KRAS mutant and wild-type amplified cancers
Poster ID: 418
Session: Novel Antitumor Agents 1
Date/Time: 4/19/2026 2PM – 5PM PT
Location: Poster Section 17, Poster Board Number: 21
ETX-880 (Covalent WRN Inhibitor)
Title: ETX-880, a potential best-in-class, oral, highly potent and selective covalent inhibitor of Werner helicase for the treatment of microsatellite instability-high (MSI-H) cancers
Poster ID: 423
Session: Novel Antitumor Agents 1
Date/Time: 4/19/2026 2PM – 5PM PT
Location: Poster Section 17, Poster Board Number: 26
About ETX-929
ETX-929 is a potent and selective oral pan-KRAS inhibitor designed leveraging ENSEM’s proprietary Kinetic Ensemble platform. ETX-929 inhibits multiple KRAS-mutant variants, including KRASG12D, KRASG12V, KRASG12C, and other clinically relevant mutations, in both the active (GTP-bound/ON) and inactive (GDP-bound/OFF) states. KRAS is the most frequently mutated oncogene in human cancers, driving approximately 25% of all solid tumors, including pancreatic, colorectal, and non-small cell lung cancers. Despite recent advances in allele-specific KRAS inhibitors, there remains a significant unmet need for pan-KRAS therapeutics that can address the full spectrum of KRAS-driven cancers. ETX-929 has demonstrated potent anti-tumor activity in preclinical models and has completed IND-enabling studies with anticipated IND clearance in Q2 2026.
About ETX-880
ETX-880 is a covalent, potent, oral inhibitor of Werner syndrome ATP-dependent helicase (WRN) designed leveraging ENSEM’s Kinetic Ensemble platform. WRN helicase has emerged as a compelling synthetic lethal target in microsatellite instability-high (MSI-H) cancers. MSI-H tumors arise from defects in the DNA mismatch repair pathway and are found across multiple tumor types, including colorectal, endometrial, gastric, and ovarian cancers. While immune checkpoint inhibitors have demonstrated clinical benefit in MSI-H cancers, 40–70% of patients either do not respond or eventually develop resistance, underscoring the need for novel therapeutic approaches. ETX-880’s covalent binding mechanism is designed to deliver deep and sustained WRN inhibition, and the compound has demonstrated selective anti-proliferative activity against MSI-H cancers in preclinical studies. ETX-880 is currently at the IND-enabling stage.
(Press release, ENSEM Therapeutics, APR 17, 2026, View Source [SID1234664502])