Exelixis, Natera announce collaboration on STELLAR-316 trial

Exelixis (EXEL) and Natera (NTRA) announced their collaboration on the planned Exelixis-sponsored STELLAR-316 trial. This randomized phase 3 pivotal trial will evaluate zanzalintinib, Exelixis’ novel oral kinase inhibitor, with and without an immune checkpoint inhibitor, in patients with resected stage II/III colorectal cancer. Using Natera’s Signatera test following completion of definitive therapy, patients with CRC who test positive for molecular residual disease and have no radiographic evidence of disease will be eligible for enrollment in the STELLAR-316 trial. Working with patients and their providers, this trial will be fully enrolled with patients who are receiving commercial Signatera testing as part of their routine standard of care. The primary endpoint of STELLAR-316 is disease-free survival. Signatera will also be used for longitudinal monitoring of circulating tumor DNA clearance, one of the secondary endpoints of the trial. Exelixis expects to initiate STELLAR-316 in mid-2026.