Kura Oncology Inc. (NASDAQ: KURA) reported preliminary clinical trial data for its cancer drug candidate darlifarnib in combination with adagrasib for treating KRAS-mutant cancers, according to a company statement.

The Phase 1a trial data showed confirmed objective response rates of 67% in pancreatic cancer patients, 50% in non-small cell lung cancer patients, and 29% in KRAS inhibitor-naïve colorectal cancer patients. The study included 26 response-evaluable patients with KRAS G12C-mutated cancers who had received previous treatments.

Tumor shrinkage was observed in 77% of all patients and 94% of patients who had not previously received KRAS inhibitor treatment. Clinical activity was also noted in patients who had been previously treated with KRAS inhibitors.

The San Diego-based biopharmaceutical company presented the data at the 2026 American Society of Clinical Oncology Annual Meeting. Kura stated the results represent the third clinical validation of its farnesyl transferase inhibitor combination approach, following previous studies in renal cell carcinoma and PIK3CA-mutated head and neck cancer.

Preclinical studies showed that darlifarnib inhibits RHEB farnesylation and suppresses mTORC1 signaling, which the company said is implicated in resistance to KRAS inhibition. The studies demonstrated enhanced anti-tumor activity across multiple classes of RAS inhibitors.

Kura plans to initiate a platform study designed to evaluate darlifarnib across multiple targeted therapy combinations. The first planned combination will be darlifarnib plus daraxonrasib in KRAS-mutant pancreatic cancer, expected to enter Phase 1a evaluation in early 2027.

The company scheduled a virtual investor event for June 3, 2026, to discuss the clinical data and development strategy.