Kronos Bio, a company dedicated to developing small molecule therapeutics that address cancers and other diseases driven by deregulated transcription, today announced the first patient dosed in an expansion cohort with KB-0742 at a dose of 80mg given on a four-days-on, three-days-off schedule. This expansion cohort is enrolling platinum-resistant patients with high-grade serous ovarian cancer (HGSOC), a tumor type which is particularly sensitive to CDK9 inhibition due to MYC amplification or overexpression and deficiencies in homologous recombination (HRD+).

“To date, KB-0742 has a safety database of over 100 patients, with no grade 3 or 4 neutropenia observed, and has shown preliminary anti-tumor activity in transcriptionally addicted solid tumors at the 60mg dose given three-days-on, four-days-off,” said Norbert Bischofberger, Ph.D., president and chief executive officer, Kronos Bio, Inc., “Pharmacokinetic modeling of 80mg four-days-on, three-days-off schedule shows a 1.8-fold increase in AUC over seven days relative to the 60mg three-days-on, four-days-off schedule. With this dose and schedule, we believe that KB-0742 will deliver therapeutic responses in this high unmet need population. We look forward to providing an update on the efficacy of KB-0742 in the first half of 2025.”

In the United States there are an estimated 22,000 new cases of ovarian cancer each year, with a five-year survival rate of less than 50%. Approximately 85% of these tumors exhibit MYC-amplification or overexpression, and 50% are HRD+.

“We are excited for the focused expansion of KB-0742 in platinum-resistant HGSOC. KB-0742 has to date provided prolonged stable disease of over 300 days in one of my platinum-resistant HGSOC patients,” said Howard “Skip” A. Burris M.D., president of Sarah Cannon Research Institute (SCRI). “HGSOC patients have limited treatment options after progressing on platinum therapy and KB-0742 brings new possibilities to those battling this devastating disease.”