Kronos Bio Announces FDA Clearance of IND for Oral CDK9 Inhibitor

Kronos Bio, Inc. recently announced US FDA clearance of the company’s Investigational New Drug (IND) application for KB-0742, a highly selective, orally bioavailable inhibitor of cyclin-dependent kinase 9 (CDK9). The company plans to begin a Phase 1/2 clinical trial of KB-0742 in patients with advanced solid tumors in the first quarter of 2021.

“CDK9 is an important transcriptional co-factor of MYC, a well-known driver of cancer that is amplified in approximately 30% of solid tumors,” said Norbert Bischofberger, PhD, President and CEO. “FDA clearance of the IND for KB-0742 marks an important milestone for this program, which was generated using our proprietary drug discovery platform. In the next few months, we look forward to initiating a first-in-human clinical trial designed to define a dose and schedule that affords appropriate target engagement and acceptable safety, setting the stage for potential further development of this promising investigational therapy.”

The open-label, Phase 1/2 clinical trial for KB-0742 will be conducted over two stages: dose escalation and expansion. The dose-escalation stage will assess the safety, pharmacokinetic (PK), and pharmacodynamic (PD) profile of KB-0742 and seek to establish a pharmacologically active dose and schedule with an acceptable safety profile. This dose and schedule will be further studied in the subsequent expansion stage in patients with MYC-amplified solid tumors and other transcriptionally addicted rare tumors, such as sarcomas and chordomas. Kronos Bio expects to report initial safety, PK and PD data from the dose-escalation stage of the study in 2021.

KB-0742 is a highly selective, orally bioavailable inhibitor of cyclin-dependent kinase 9 (CDK9) in development for the treatment of MYC-amplified solid tumors. CDK9 is a global regulator of transcription and plays an essential role in the expression and function of MYC, a well-characterized transcription factor and a long-recognized driver of cancer that is amplified in approximately 30% of solid tumors, including those affecting the lungs, ovaries, esophagus, breast, stomach, pancreas, and liver. KB-0742 was generated and optimized from a compound that was identified using the company’s proprietary small molecule microarray (SMM) screening platform.

Kronos Bio is a clinical-stage biopharmaceutical company dedicated to discovering, developing, and commercializing therapies that seek to transform the lives of those affected by cancer. The company focuses on targeting dysregulated transcription factors and the regulatory networks within cells that drive cancerous growth. Kronos Bio’s lead investigational therapy is entospletinib, a selective inhibitor targeting spleen tyrosine kinase (SYK) in development for the frontline treatment of NPM1-mutated acute myeloid leukemia (AML). The company is also developing KB-0742, an oral inhibitor of cyclin dependent kinase 9 (CDK9), for the treatment of MYC-amplified solid tumors. Kronos Bio is based in San Mateo, CA, and has a research facility in Cambridge, MA. For more information, visit www.kronosbio.com.