Dr. Sumanta K. Pal on atezolizumab/cabozantinib results in urothelial carcinoma

Sumanta K. Pal, MD, City of Hope Comprehensive Cancer Center, highlights results from the phase 1b COSMIC-021 trial he presented at the 2022 ASCO Annual Meeting. In the study, the combination of cabozantinib (Cabometyx) and atezolizumab (Tecentriq) showed promising clinical activity with manageable toxicity across several setting in patients with urothelial carcinoma (UC).

Overall, the multicenter, open-label COSMIC-021 trial (NCT03170960) is evaluating the combination of the PD-L1 inhibitor atezolizumab and the multikinase inhibitor cabozantinib in patients with locally advanced or metastatic solid tumors. This analysis included patients with inoperable locally advanced/metastatic UC with transitional cell histology and ECOG performance status (PS) of 0-1.

Among the enrolled patients, those in study cohorts 3 (C3) had no prior systemic therapy and were cisplatin ineligible. Patients in study cohort 4 (C4) were also systemic treatment–naïve but were cisplatin eligible, and study cohort 5 (C5) comprised patients who had received 1 prior immune checkpoint inhibitor (ICI), were VEGFR-TKI–naïve, and had received ≤2 lines of therapy overall.

The results showed that 1 patient in C3, 2 patients in C4, and no patients in C5 had complete responses (CRs). Partial responses (PRs) were reached by 5, 7, and 3 patients in C3, C4, and C5, respectively. The objective response rates (ORRs) were 20%, 30%, and 10%, respectively, and the disease control (CR + PR + stable disease) rates were 80%, 63%, and 61%, respectively.