Exelixis Delays Zanzalintinib-Tecentriq FDA Decision To March 2027, After Agency Requests Updated Data

Exelixis said the FDA has delayed its approval decision for zanzalintinib in combination with Roche’s Tecentriq for patients with metastatic colorectal cancer. In a Securities and Exchange Commission filing, the company said the agency requested the extension while it awaits updated safety and efficacy data.

The delay moves the expected decision to March 2027 from the previous Dec. 3, 2026 deadline. For Exelixis, that changes the timing of a key late-stage program and suggests the review has shifted from a straightforward label decision to a closer look at the totality of the package.

The road here

The application was already facing questions after zanzalintinib missed one of the primary endpoints in June, specifically overall survival in a subpopulation of phase 3 metastatic colorectal cancer patients. That result cut into momentum that had built after the drug showed significantly longer overall survival in a phase 3 head-to-head study against Bayer’s Stivarga last year.

Even after the June miss, Leerink Partners and William Blair had argued that the FDA would likely still approve zanzalintinib in third-line metastatic colorectal cancer because the trial had previously met the other primary endpoint of overall survival in all study participants, regardless of liver metastases status. William Blair said in a Sept. 11 note that the risk of rejection for the zanzalintinib-Tecentriq combination remains low because of the broader phase 3 data, while also saying it is difficult to speculate on the FDA’s reason for seeking updated safety and efficacy information.

Why the delay matters

Zanzalintinib is an oral multi-targeted kinase inhibitor that binds and inhibits multiple receptor tyrosine kinases implicated in cancer. The immediate issue is not whether the mechanism is credible, but how much regulatory weight the FDA gives to the positive overall survival result in the full study population relative to the failed endpoint in a defined subpopulation.

That matters beyond this one filing because Exelixis is running multiple other phase 3 studies with zanzalintinib, including Stellar-311 in neuroendocrine tumors and Stellar-304 in non-clear cell renal cell carcinoma, with Stellar-304 expected to read out in the second half of this year. Analysts have suggested the drug could generate $4.5 billion in U.S. sales in 2033 across genitourinary and gastrointestinal cancers, so a longer and more data-driven review in colorectal cancer could influence how investors frame the broader franchise.

In metastatic colorectal cancer, Exelixis is pursuing a market that includes Stivarga, Amgen’s Lumakras and Takeda’s Fruzaqla.