Results from the phase 1b COSMIC-021 study of cabozantinib in combination with atezolizumab in people with previously untreated advanced renal cell carcinoma (RCC) were presented at the European Society for Medical Oncology (ESMO) 2018 Congress in Munich over the weekend.
This dose-escalation study primarily looked at the safety of the cabozantinib + atezolizumab combination in untreated advanced RCC patients to determine the best dose to use in future clinical trials. The combination showed encouraging clinical activity in this group of patients, and the best dose of cabozantinib was found to be 40 mg in combination with the standard dose of atezolizumab.
Eighty percent of the 10 patients with clear cell RCC responded to treatment. Among all 12 patients enrolled, including the 2 non-clear cell RCC patients, the response rate was 67%. The disease control rate for all 12 patients was 100%.
No dose-limiting toxicities or serious adverse events were noted at either cabozantinib dose (40 mg or 60 mg) and there were no life-threatening adverse events during the study.
“These early stage results demonstrate that the combination of cabozantinib and atezolizumab was well tolerated and showed promising anti-tumour activity in advanced kidney cancer,” said Dr Sumanta Kumar Pal, associate clinical professor, Department of Medical Oncology and Therapeutics Research, co-director, Kidney Cancer Program, City of Hope. “We look forward to continuing to advance this trial to understand whether this combination may benefit patients with multiple tumour types.”