Exelixis shares fell roughly 3.5% in pre-market trading on Friday, September 11, after the company disclosed that the FDA had extended the review of its metastatic colorectal cancer drug combination by three months. The new decision date is March 3, 2027. For a stock trading near a 52-week high of $59.72, that kind of move registers as a shrug more than a signal.
The mechanics of the delay are straightforward. In response to an FDA information request, Exelixis submitted updated safety and efficacy data on its experimental regimen, zanzalintinib paired with Roche’s atezolizumab (Tecentriq). The agency classified that submission as a major amendment, which automatically triggers a standard three-month extension to the review clock. The original PDUFA date was December 3, 2026. It is now March 3, 2027.
This is a delay, not a rejection. The distinction matters. What the FDA classified was the scope of new data Exelixis provided, not the acceptability of the application itself. The underlying trial, STELLAR-303, randomized 901 patients and showed a statistically significant improvement in overall survival versus regorafenib in the intention-to-treat population, with a hazard ratio of 0.80 and a p-value of 0.0045. Median overall survival was 10.9 months for the combination versus 9.4 months for the comparator. The second primary endpoint, overall survival in patients without active liver metastases, did not cross the significance threshold, which is the data wrinkle worth watching when the FDA eventually weighs in.
What Cabozantinib Is Actually Paying For
Here is the more useful framing for investors: Exelixis does not need zanzalintinib to stay solvent. Cabometyx (cabozantinib) generated $573.0 million in U.S. net product revenues in Q2 2026 alone, up about 10% year over year. The global franchise, including royalties from partners Ipsen and Takeda, hit $806 million in Q2, up 13%.
Revenue guidance for fiscal 2026 sits at $2.500 billion to $2.550 billion in total revenues, and that figure deliberately excludes any contribution from a potential zanzalintinib launch. Exelixis built its financial model for a world where the new drug does not arrive this year. The delay merely confirms that world extends into early 2027.
The question for anyone holding the stock near its highs is whether the valuation reflects the cabozantinib franchise that exists today, or the second commercial engine that management has been promising. Analysts see zanzalintinib as a key growth driver, aiming at a market that Exelixis has pegged at roughly $1.5 billion for third-line-plus colorectal cancer patients. That is a meaningful opportunity on top of a franchise already generating over $2 billion annually. But it is also still an application under review, with one mixed primary endpoint and a harder FDA ask now on the table.
The Risk Is Concentration, Not the Calendar
Three months of additional review time does not fundamentally alter the investment case in either direction. What it does do is extend the period during which Exelixis remains, by its own admission, overwhelmingly dependent on a single drug. Cabometyx accounts for nearly all of the company’s product revenue. Zanzalintinib was supposed to start reducing that concentration. It still could, just on a slightly later timeline.
The pipeline beyond colorectal cancer adds some optionality. Exelixis is running additional zanzalintinib pivotal trials across non-clear cell renal cell carcinoma, neuroendocrine tumors, and resected colorectal cancer, the latter in collaboration with Merck and Natera. None of those readouts are imminent.
At current levels, the stock is pricing in continued cabozantinib growth and a reasonable probability of zanzalintinib approval. The FDA’s action does not invalidate either assumption. It does, however, make March 2027 a much more consequential date on the calendar than it was a week ago. That is worth knowing before adding exposure near the 52-week high.
Rising Star Stocks