New Experimental Drug Outperforms Standard Therapy in Advanced Kidney Cancer

Results from randomized phase II clinical trial by researchers at Dana-Farber Cancer Institute revealed that a new experimental kidney cancer drug worked better than the standard first-line therapy for patients with metastatic disease.

Their findings, published in the Journal of Clinical Oncology, showed that people who received the experimental drug cabozantinib had a longer time before their cancer worsened than those taking sunitinib (Sutent), which is considered to be the initial drug treatment for metastatic kidney cancer for the last 10 years.

"These results are very relevant to our practice and our kidney cancer patients - they may change the standard," said Toni K. Choueiri, MD, director of the Lank Center for Genitourinary Oncology at Dana-Farber and lead author of the study, in a press release. "The results also demonstrate that studies sponsored by the National Cancer Institute can accrue rapidly and yield highly relevant results to the field."

The clinical trial included 157 patients with metastatic clear cell renal cell carcinoma (RCC). The trial was conducted to cabozantinib and sunitinib as initial treatment for advanced kidney cancer. While both drugs blocks angiogenesis by targeting vascular endothelial growth factor (VEGF) and its receptors, cabozantinib also blocks the MET and AXL oncogenes, both involved in resistance to VEGF inhibitors. Both drugs have similar or comparable safety and side effect profiles as to those observed in kidney cancer patients treated with other VEGF inhibitors

The researchers observed that the median rate of progression in cabozantinib was 8.2 months, while sunitinib was 5.6 months. Cabozantinib was able to reduce the rate of disease progression by 34 percent compared with sunitinib. Furthermore, patients in the cabozantinib group experienced a better overall response rate compared to patients in the sunitinib group, 46 percent and 18 percent, respectively.

Despite not being designed to compare the overall survival rates between the drugs, the clinical trial showed that the patients who received the cabozantinib treatment were 20 percent less likely to die as a direct result of the disease.