Exelixis' XL092/ Atezolizumab Shows Encouraging Efficacy, Safety In Heavily Pretreated Cancer Patients

Exelixis Inc EXEL announced results from the dose-escalation stage of STELLAR-001, an ongoing phase 1b trial evaluating XL092 as a single agent and in combination with atezolizumab for locally advanced or metastatic solid tumors.
The maximum tolerated dose was determined to be 120 mg, and the recommended dose for the expansion phase is 100 mg for both single-agent XL092 and XL092 in combination with atezolizumab.
Tumor reduction was seen in 71% of patients receiving single-agent XL092 and in 56% of patients receiving XL092 in combination with atezolizumab.
The objective response rate (ORR) was 10% for single-agent XL092 and 4% for XL092 in combination with atezolizumab, with a disease control rate (DCR) of 90% and 74%, respectively.
Confirmed partial responses were observed in four patients treated with single-agent XL092 and one treated with XL092 in combination with atezolizumab.
In the 19 patients with clear cell RCC, ORR was 11%, and DCR was 95% with single-agent XL092.
XL092 showed a similar reduction in tumor size (RTS). XL092 demonstrated a 71% RTS versus 74% with cabozantinib; a greater than 30% RTS was seen in 15% of patients treated with XL092 versus 18% of those treated with cabozantinib.
Price Action: EXEL shares closed at $17.81 on Friday.