Kura Oncology Inc. (NASDAQ: KURA) reported preliminary clinical trial data showing its experimental drug darlifarnib combined with cabozantinib demonstrated antitumor activity in patients with clear cell renal cell carcinoma who had previously been treated with cabozantinib.

The subset analysis from the ongoing FIT-001 clinical trial involved 16 patients with ccRCC who had received prior cabozantinib treatment. According to data presented at the 2026 International Kidney Cancer Symposium in Paris, the combination achieved a 44% objective response rate and 94% disease control rate across all tested doses.

Tumor shrinkage occurred in 75% of patients, with reductions ranging from 32% to 47% among those who responded. Treatment durations ranged from 8 to 56 weeks, with six patients remaining on therapy at the time of data analysis.

The study evaluated darlifarnib at daily doses of 3 mg, 5 mg or 8 mg given in alternating 7-day cycles, combined with cabozantinib at 60 mg or 40 mg daily. All patients had received prior immunotherapy. The trial has advanced to Phase 1b dose expansion to determine optimal dosing.

"These data highlight the potential of darlifarnib to overcome resistance to prior cabozantinib and enhance the activity of VEGF TKIs in patients with advanced RCC," said Mollie Leoni, Kura Oncology's chief medical officer, according to the company's press release.

The findings address a treatment challenge for patients whose cancer progresses after cabozantinib therapy, as this population typically has limited subsequent treatment options and poor response rates to further cabozantinib-based therapy.

Kura Oncology is a San Diego-based biopharmaceutical company focused on precision cancer medicines. The company recently received FDA approval for KOMZIFTI, a treatment for certain types of acute myeloid leukemia.