Finvest
EXEL Biotechnology · Oncology · Commercial-stage biotech · Thesis updated July 12, 2026

Cabo funds the next Exelixis bet

01 Running thesis

One big drug, one big follow-up

Exelixis is in a stronger spot than many biotech companies because it already makes real money. CABOMETYX, its brand name for cabozantinib, funds the company while it runs trials and buys back stock. In Q1 2026, U.S. CABO franchise net product revenue grew 8% year over year to $555 million, and management said the quarter had the highest number of new CABOMETYX patient starts ever.

The bull case is simple. Cabo is still growing in kidney cancer and is off to a strong start in neuroendocrine tumors. The company also has a clear path to a second major franchise if the FDA approves zanzalintinib for colorectal cancer on December 3, 2026.

The bear case is also simple. Until zanzalintinib is approved and starts selling, Exelixis is still mostly a one-product story. The next major zanzalintinib kidney cancer readout, STELLAR-304, moved to the second half of 2026, which leaves more weight on the colorectal cancer review and the cabo sales trend.

Finn's view is balanced. Exelixis has strong current performance and financial health, but the stock still needs proof that the next drug can become more than a pipeline promise.

May 2026The Q1 2026 10-Q confirmed the December 3, 2026 PDUFA date for zanzalintinib in colorectal cancer and listed no material risk-factor changes.
May 2026Management moved the STELLAR-304 readout to the second half of 2026. That delays a key proof point for zanzalintinib in kidney cancer.
Feb 2026The FDA accepted the zanzalintinib NDA in colorectal cancer. CABOMETYX also passed $100 million of U.S. cabo revenue from neuroendocrine tumors in 2025.
Nov 2025The NET launch was ahead of expectations, with management citing more than 40% new patient share in the oral second-line plus NET segment. Exelixis also prepared to file zanzalintinib for colorectal cancer.
Jul 2025Positive STELLAR-303 colorectal cancer data strengthened the zanzalintinib case. The update was tempered by the end of STELLAR-305 in head and neck cancer and a delay in STELLAR-304.
02 Business model

Cabo pays the bills

Exelixis makes most of its money by selling CABOMETYX in the United States. It also receives collaboration revenue, mainly royalties from Ipsen and Takeda, which sell cabozantinib outside the United States.

In Q1 2026, Exelixis reported $610.8 million of total revenue. Net product revenue was $555.0 million, while collaboration revenue was $55.8 million. That means the business is heavily tied to U.S. cabo demand.

The company uses this cash to fund cancer trials, especially zanzalintinib, and to support business development. This model works well when cabo keeps growing and trials hit. It breaks if payers cut net prices, doctors switch to rivals, or zanzalintinib fails to win approval.

03 Product portfolio

What Exelixis sells and tests

Cash cow

CABOMETYX in renal cell carcinoma

This is Exelixis's core market. RCC is kidney cancer, and CABOMETYX is the number one prescribed TKI there.

Growth engine

CABOMETYX in neuroendocrine tumors

The FDA approved CABOMETYX for pNET and epNET in 2025. U.S. cabo revenue from this use passed $100 million in 2025, its first year on the market.

Growth engine

Zanzalintinib in colorectal cancer

This is the key next-drug bet. The FDA accepted the NDA for zanzalintinib plus atezolizumab, with a December 3, 2026 PDUFA decision date.

Option

Zanzalintinib in non-clear cell RCC

STELLAR-304 tests zanzalintinib plus nivolumab against sunitinib in untreated non-clear cell kidney cancer. Top-line results are expected in the second half of 2026, depending on event rates.

Option

Early oncology pipeline

Exelixis is testing earlier drugs such as XL309, XB010, XB628, and XB371. These could matter later, but they are not the main value driver today.

Steady

Partnered legacy products

COTELLIC and MINNEBRO came from Exelixis research and are marketed through partners. They add breadth, but cabo remains the main business.

04 Business segments

Revenue is still concentrated

Net product revenues91%modest
Collaboration revenues9%growing fast

The mix uses Q1 2026 revenue from the latest 10-Q. Net product revenue was about 91% of total revenue, so Exelixis still depends mostly on U.S. cabozantinib sales.

05 Risk factors

What could go wrong

Zanzalintinib label disappoints

High impact · Medium odds

The FDA has accepted the colorectal cancer application, so the key risk has moved from trial data to the final regulatory decision. Approval is not guaranteed, and the label could be narrower than investors hope, especially around the non-liver metastasis population.

We watchFDA action on the December 3, 2026 PDUFA date and any wording on the approved patient group.

STELLAR-304 data miss or slip again

High impact · Medium odds

STELLAR-304 is the next major zanzalintinib kidney cancer trial. Management moved the expected readout to the second half of 2026 because event rates affect timing. A weak result would hurt the case that zanzalintinib can become a broad franchise.

We watchTop-line STELLAR-304 results and whether the readout timing changes again.

Cabo growth slows

High impact · Medium odds

Most revenue still comes from cabozantinib. If kidney cancer share weakens or the neuroendocrine tumor launch fades after the early surge, Exelixis would have less growth while it waits for zanzalintinib.

We watchQuarterly U.S. CABO franchise net product revenue and management comments on new patient starts.

Payer discounts pressure margins

Medium impact · Medium odds

Management guided 2026 gross-to-net to 31% to 32%. Gross-to-net is the gap between list price and what the company keeps after rebates, discounts, and fees. A higher number means Exelixis keeps less of each sale.

We watchGross-to-net guidance and commentary on 340B and other discounted channels.

Competition changes doctor habits

Medium impact · Medium odds

CABOMETYX competes with other TKIs and immune therapy combinations. It leads in renal cell carcinoma today, but doctors can change prescribing if rivals show better data, cleaner safety, or easier use.

We watchMarket share data in RCC and NET, plus new trial results from competing cancer drugs.
06 Quick answers

In one breath

How does Exelixis make money?

Exelixis mainly sells CABOMETYX in the United States. It also earns collaboration revenue, including royalties from Ipsen and Takeda for cabozantinib sales outside the United States.

What is the biggest upcoming Exelixis catalyst?

The biggest dated catalyst is the FDA decision for zanzalintinib in colorectal cancer on December 3, 2026. Investors will also watch STELLAR-304 data in non-clear cell kidney cancer in the second half of 2026.

Why does concentration risk matter for EXEL?

Most current revenue depends on cabozantinib. If CABOMETYX loses share, faces access pressure, or has a safety issue, Exelixis would feel it quickly because zanzalintinib is not yet a major seller.