On June 22, 2026 Exelixis, Inc. (Nasdaq: EXEL) reported results from the final analysis of the dual primary endpoint of overall survival (OS) in the subset of patients without active liver metastases (non-liver metastases, NLM) in the phase 3 STELLAR-303 pivotal trial evaluating zanzalintinib in combination with atezolizumab (Tecentriq) versus regorafenib in previously treated non-microsatellite instability (MSI)-high metastatic colorectal cancer (mCRC). The results showed a non-statistically significant trend in OS favoring the combination in the NLM subpopulation (stratified hazard ratio: 0.83; 95% confidence interval: 0.66–1.05; P=0.1185), with median OS values of 15.9 months with zanzalintinib in combination with atezolizumab, and 12.7 months with regorafenib.

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The safety profile of zanzalintinib in combination with atezolizumab in the NLM subgroup was consistent with that previously reported in the intention-to-treat (ITT) population, and no new safety signals were identified.

Exelixis previously announced that STELLAR-303 met its other dual primary endpoint, demonstrating a statistically significant improvement in OS in the ITT population, which included all randomized patients regardless of the presence of active liver metastases. Detailed results demonstrating the statistically significant improvement in OS in the ITT population were presented at the 2025 European Society for Medical Oncology Congress and published in The Lancet.

In February 2026, Exelixis announced that the U.S. Food and Drug Administration (FDA) accepted the company’s New Drug Application (NDA) for zanzalintinib, in combination with atezolizumab, for the treatment of patients with mCRC who have been previously treated with fluoropyrimidine-, oxaliplatin- and irinotecan-based chemotherapy, and, if RAS wild-type, an anti-epidermal growth factor receptor (EGFR) therapy. The FDA assigned a Prescription Drug User Fee Act target action date of December 3, 2026.

Detailed findings from the NLM subgroup analysis will be submitted for presentation at an upcoming medical conference.

About STELLAR-303
STELLAR-303 (NCT05425940) is a global, multicenter, randomized, phase 3, open-label study that randomized patients 1:1 to either zanzalintinib in combination with atezolizumab (n=451) or regorafenib (n=450). The study includes patients with previously treated non-MSI-high mCRC. The dual primary endpoints of the study are OS in the ITT population and in the NLM subgroup of patients. The ITT population consisted of all randomized patients, regardless of the presence of liver metastases. The NLM subgroup consisted of patients who did not have active liver metastases at baseline as determined by investigator assessment. Secondary endpoints include progression-free survival, objective response rate and duration of response in the ITT population and in the NLM subgroup of patients. More information about the trial is available at ClinicalTrials.gov.

About Zanzalintinib
Zanzalintinib is a novel oral kinase inhibitor that inhibits the activity of the TAM kinases (TYRO3, AXL, MER), MET and VEGF receptors. These kinases play important roles in oncogenic processes, including tumor cell proliferation, metastasis, angiogenesis, drug resistance and evasion of antitumor immunity. The zanzalintinib development program includes a series of ongoing and planned pivotal trials to explore its therapeutic potential in CRC, clear cell and non-clear cell renal cell carcinoma, and neuroendocrine tumors, as well as earlier-stage trials in meningioma, lung cancer and castration-resistant prostate cancer.

Zanzalintinib is an investigational agent that is not approved for any use and is the subject of ongoing clinical trials.

About CRC
CRC is the third most common cancer and a leading cause of cancer-related deaths in the U.S.1 Approximately 159,000 new cases will be diagnosed in the U.S. in 2026, with around 55,000 expected deaths from the disease.1 CRC is most frequently diagnosed among people aged 65-74 and is more common in men and in people of non-Hispanic American Indian/Alaska Native descent.2 Nearly a quarter of CRC cases are diagnosed at the metastatic stage, at which point the five-year survival rate is around just 15%.1,2 The liver is the most common site for CRC metastasis. Liver metastases significantly impact survival, with a median five-year survival rate of less than 14% when treated with palliative chemotherapy.

(Press release, Exelixis, JUN 22, 2026, View Source [SID1234668861])