EXEL Collaborates With Natera for Late-Stage Colorectal Cancer Study

Exelixis, Inc. EXEL announced that it has collaborated with Natera NTRA for the STELLAR-316 study.

This phase III study is being sponsored by Exelixis.

The study will evaluate Exelixis’ novel oral kinase inhibitor, zanzalintinib, with and without an immune checkpoint inhibitor, in patients with resected stage II/III colorectal cancer (CRC).

Exelixis stock was up 6% on Jan. 7, following the news.

Exelixis’ shares have risen 33.9% in the past year compared with the industry’s gain of 17.2%.

Additional Data on EXEL’s STELLAR-316 Study

Exelixis expects to initiate STELLAR-316 in mid-2026.

Zanzalintinib is a novel oral kinase inhibitor that inhibits the activity of the TAM kinases (TYRO3, AXL, MER), MET and VEGF receptors.

Patients with CRC who are molecular residual disease (MRD)-positive based on Natera’s Signatera test following completion of definitive therapy — and who have no radiographic evidence of disease — will be eligible for enrollment in the STELLAR-316 trial.

The study will be fully enrolled with patients who receive commercial Signatera testing as a part of their routine standard of care.

The primary endpoint of the STELLAR-316 trial is disease-free survival. Signatera will also be used to longitudinally assess circulating tumor DNA clearance, a key secondary endpoint.

STELLAR-316 is Exelixis’ second pivotal study of zanzalintinib in patients with CRC.

Exelixis is upbeat about its collaboration with Natera on STELLAR-316, which, if successful, could position zanzalintinib as the first MRD-guided treatment option for these patients.

More on EXEL’s Zanzalintinib

Zanzalintinib is currently being evaluated for the treatment of advanced solid tumors, including CRC, kidney cancer and neuroendocrine tumors.

Exelixis recently confirmed the submission of a new drug application (NDA) to the FDA seeking approval of zanzalintinib, in combination with Roche’s RHHBY Tecentriq (atezolizumab), for the treatment of patients with previously treated metastatic colorectal cancer. The NDA is supported by positive results from the late-stage STELLAR-303 pivotal study, which met one of its dual primary endpoints.

At the final analysis, the combination of zanzalintinib and Tecentriq demonstrated a statistically significant reduction in the risk of death compared with Stivarga (regorafenib) in the intention-to-treat population.

Roche’s Tecentriq is a cancer immunotherapy that is approved around the world, either alone or in combination with targeted therapies and/or chemotherapies, for various types of cancers.

An overall survival benefit was observed consistently across prespecified subgroups, including geographic region, RAS mutation status, liver involvement, and prior anti-VEGF therapy. Data for the second dual primary endpoint — overall survival in patients without liver metastases (non-liver metastases, or NLM) — were immature at the time of data cutoff. A prespecified interim analysis showed a favorable trend in overall survival for the combination. The trial will continue to the planned final analysis for this endpoint, which is expected in mid-2026 based on current event rates.

In July 2025, Exelixis announced multiple updates to its zanzalintinib development program. This included the initiation of the phase III STELLAR-311 study in advanced neuroendocrine tumors (NET). STELLAR-311 is comparing zanzalintinib with everolimus as a first oral therapy in patients with advanced NET, irrespective of tumor site of origin.

Exelixis also noted that planning is underway for the next wave of pivotal zanzalintinib trials, including studies in post-chemotherapy adjuvant colorectal cancer settings and in patients with high-grade and/or recurrent meningiomas.

We remind investors that Exelixis is currently looking to expand its oncology portfolio beyond lead drug Cabometyx, approved for advanced renal cell carcinoma and previously treated hepatocellular carcinoma.

In March 2025, Exelixis received FDA approval for a label expansion of Cabometyx to treat adult and pediatric patients aged 12 years and older with previously treated, unresectable, locally advanced or metastatic, well-differentiated pancreatic neuroendocrine tumors (pNET) and extra-pancreatic neuroendocrine tumors (epNET).

The successful development of zanzalintinib should broaden EXEL’s portfolio and reduce dependence on its lead drug, Cabometyx.

EXEL’s Zacks Rank and Stocks to Consider

Exelixis currently carries a Zacks Rank #3 (Hold). A couple of better-ranked stocks in the pharma/biotech sector are CorMedix CRMD and Amicus Therapeutics FOLD, each carrying a Zacks Rank #1 (Strong Buy) at present. You can see the complete list of today’s Zacks #1 Rank stocks here.

In the past 60 days, estimates for CorMedix’s 2025 EP6 have increased from $2.49 to $2.88. CorMedix’s earnings beat estimates in each of the trailing four quarters, with an average surprise of 27.04%.

In the past 60 days, estimates for Amicus Therapeutics’ 2026 EPS have decreased to 67 cents from 70 cents. Shares of FOLD have gained 51.1% in a year. 


 

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