In continuation of my update on cabozantinib
Patients with advanced kidney cancer live for nearly twice as long without their disease progressing if they are treated with cabozantinib, a drug that inhibits the action of tyrosine kinases - enzymes that function as an "on" or "off" switch in many cellular processes, including cancer.
In the second of two late-breaking presentations of research that is predicted to change the way kidney cancer patients are treated, Professor Toni Choueiri will tell the presidential session of the 2015 European Cancer Congress, about results from the first 375 patients out of a total of 658 patients recruited to the phase III clinical METEOR trial comparing cabozantinib with everolimus, the current standard treatment for the disease.
Analysis of results in July 2015 showed that the estimated median (average) progression-free survival time for patients with advanced clear cell kidney cancer, randomised to receive cabozantinib, was 7.4 months, while it was 3.8 months for those receiving everolimus. The objective response rate (the proportion of patients whose tumours shrank, assessed up to 17 months) was 21% for cabozantinib and 5% for everolimus.
An interim analysis of overall survival among all of the 658 patients found that it was a third better for patients receiving cabozantinib. The findings are published simultaneously with the ECC2015 presentation in the New England Journal of Medicine.
Prof Choueiri, who is Associate Professor of Medicine at Harvard Medical School and Clinical Director and Kidney Cancer Center Director at The Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute, USA, said: "I am very excited about the outcome of the study since the results may change the standard of care in patients with advanced kidney cancer who have received prior standard therapy that targets the vascular endothelial growth factor receptor (VEGFR).
"Although treatment with VEGFR-targeted drugs has been very effective in the first line of therapy for patients with advanced kidney cancer, in many cases tumour cells find ways to escape control by these drugs. Cabozantinib is a new drug that targets possible escape mechanisms of tumour cells, including the tyrosine kinases MET, VEGFR and AXL. The results of the METEOR trial indicate that cabozantinib is able to shrink tumours and slow down tumour growth much better than current standard treatment in patients who previously received VEGFR-targeted drugs. This has resulted in a significant reduction in the rate of disease progression or death in the cabozantinib arm as compared with the everolimus arm. Regaining tumour control after prior targeted therapy may reduce symptoms related to kidney cancer and eventually help patients live longer.