Exelixis announced results from two analyses evaluating the effect of PD-L1 expression or prior treatment with immune checkpoint inhibitors on the efficacy of cabozantinib in patients with advanced renal cell carcinoma. An analysis of data from the CABOSUN and METEOR trials demonstrated that cabozantinib improved clinical outcomes regardless of PD-L1 status in patients with advanced RCC, relative to sunitinib or everolimus, the respective comparator arms for each trial. Tumor tissue from 110 patients in the CABOSUN trial and 306 patients in the METEOR trial were evaluated to determine whether PD-L1 expression predicted outcomes or response to treatment. The findings showed that PD-L1 expression was associated with shorter median progression-free survival and overall survival in both METEOR and CABOSUN. Treatment with cabozantinib, however, improved PFS and OS compared with everolimus and sunitinib in both PD-L1 positive and PD-L1 negative patients. An additional analysis evaluating the activity of cabozantinib in 69 patients with advanced RCC who progressed on immune checkpoint inhibitors found that cabozantinib was active in patients previously treated with immune checkpoint inhibitors, either alone or in combination with anti-VEGF or other therapies. At a median follow-up of 12 months, objective response rate was 33%, disease control rate was 79 percent and the one-year overall survival rate was 53%.
