Kura Oncology, Inc. reported preclinical data supporting the potential of its farnesyl transferase inhibitor (FTI) tipifarnib to prevent emergence of resistance to the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor osimertinib in EGFR mutant non-small cell lung cancer (NSCLC). The new findings, generated through a collaboration with INSERM (the French National Institute of Health and Medical Research), are being presented at the American Association for Cancer Research Annual Meeting in New Orleans. Using Rho-pathway inhibitor screening, researchers at INSERM found that tipifarnib induced a complete clearance of drug-tolerant dormant cells, a potential mechanism of resistance to EGFR-targeted therapy in NSCLC.

Several farnesylated targets were identified that appear to control the ability of tumor cells to enter and exit a drug-tolerant state. In parallel, using preclinical in vivo models of EGFR-mutated lung tumors, co-treatment with tipifarnib durably prevented relapse to osimertinib for up to six months, with no evidence of toxicity. Collectively, this mechanistic and translational research strongly supports the potential use of a FTI to prevent or delay the adaptive response to osimertinib in patients with EGFR-mutated NSCLC.

Kura is preparing to initiate a Phase I clinical trial (KURRENT-LUNG) of tipifarnib in combination with osimertinib in treatment-naïve locally advanced/metastatic EGFR mutated NSCLC and expects to dose the first patient in the third quarter of 2022. The Company intends to perform initial clinical evaluation with tipifarnib while in parallel advancing KO-2806, the lead development candidate in its next-generation FTI program, through investigational new drug (IND)-enabling studies. Kura plans to submit an IND application for KO-2806 in the fourth quarter of 2022.