Kronos Bio Highlights Data at AACR Ovarian Cancer Research Symposium that Supports Clinical Evaluation of Istisociclib in Advanced Ovarian Cancer

Core Insights - Kronos Bio, Inc. presented new preclinical data on istisociclib (KB-0742), a CDK9 inhibitor, demonstrating its potential to induce cell death in platinum and PARP-inhibitor resistant ovarian cancer models [1][3] - The company is currently conducting a Phase 1/2 clinical trial to evaluate istisociclib's efficacy as a single agent in platinum-resistant high-grade serous ovarian cancer (HGSOC) [2] Preclinical Findings - Istisociclib triggered apoptosis and cell death, evidenced by the accumulation of γH2AX, a marker of DNA damage [4] - The drug disrupted homologous recombination DNA repair by downregulating BRCA1 and RAD51, creating a "BRCAness" phenotype in resistant ovarian cancer cells [4] Clinical Trial Insights - New pharmacokinetic/pharmacodynamic (PK/PD) results from the ongoing trial showed that istisociclib administered at 80mg on a 4 days on/3 days off schedule resulted in a long half-life of approximately 24 hours [4] - Clinical exposures were consistent with efficacious levels observed in preclinical models, leading to sustained downregulation of CDK9-dependent genes in peripheral blood mononuclear cells (PBMCs) [4] Company Overview - Kronos Bio is focused on developing small molecule therapeutics targeting deregulated transcription, a key feature of cancer and other diseases [5] - The company has a preclinical pipeline and two drug candidates, including istisociclib targeting CDK9 and KB-9558 targeting p300 for multiple myeloma [5]