Exelixis Trims Guidance on NET's Slower Ramp, but Zanza Looms as Next Growth Engine
Exelixis reported second-quarter 2026 results that beat on the bottom line but trimmed full-year revenue guidance as the neuroendocrine tumor (NET) ramp proved more gradual than initially expected. The company’s next franchise molecule, zanzalintinib (zanza), continues to advance through a broad pivotal program, and the stock has responded positively, climbing 22% over the last 90 days. The real story is not the modest guide-down, but the pipeline breadth and the company’s ability to fund it while returning cash to shareholders.
The Guide Down: NET's Slower Ramp Hits Revenue Guidance
Management lowered the midpoint of total revenue and net product revenue guidance by $50 million, citing a more gradual uptake for CABOMETYX in the second-line plus NET setting. As P.J. Haley noted in prepared remarks: “The revenue growth for the first half of 2026 was modestly slower than we had anticipated due to a more gradual ramp in the growth of NET in the second-line plus setting due to patient kinetics.” — P. Haley, Unspecified Executive (likely Commercial or Strategy) · 2026-08-05 The rationale is that NET patients are more indolent and have slower treatment dynamics, often leading to treatment breaks or delayed progression to subsequent lines. Despite this, the company stresses that market share in the oral second-line plus segment has exceeded 45%, forecasting future growth as those patients eventually initiate therapy.
In the Q&A, Haley reiterated confidence in the franchise:
This gradual ramp is a company-specific theme, distinct from broad sector dynamics, and has directly prompted the NET indication to become the key focus of the guidance adjustment.I remain really excited about the opportunity in NET. We're not really changing the outlook at all. As you mentioned, it's just kind of the ramp is a little more gradual, but we're excited that we achieved a new patient market share over 45% this quarter.
The updated guidance also includes a $50 million reduction in R&D expense guidance midpoints, reflecting disciplined capital allocation rather than a loss of confidence in the pipeline. Chris Senner, CFO, explained: “We are lowering and narrowing our total revenues and net product revenue guidance, which lowers the midpoint by $50 million when compared to our previous guidance.” — Christopher Senner, Chief Financial Officer · 2026-08-05
Zanzalintinib: The Story Remains Intact
While the NET ramp is slower, the strategic emphasis is clearly on zanzalintinib as the next major franchise. The STELLAR-303 NDA for third-line plus colorectal cancer has a PDUFA date in December, and preparations are in full swing. Dana Aftab highlighted the breadth of the pivotal program: “We completed enrollment in STELLAR-304 last year. And given current event rates, we continue to expect top line results from the study in the second half of 2026.” — Dana Aftab, Executive Vice President of Research and Development · 2026-08-05 If positive, STELLAR-304 could lead to a second NDA filing for zanza in non-clear cell renal cell carcinoma, an underserved population with no established standard of care.
The development plan extends well beyond CRC and RCC, with trials in meningioma (STELLAR-201) and squamous non-small cell lung cancer (STELLAR-202) expected to initiate this year. This breadth was summarized in Mike Morrissey’s prepared remarks about the five key elements of the strategy: ZANZA in patients across multiple tumor types, with patient kinetics being a focal point for the NET understanding.
Financial Discipline and Shareholder Returns
Exelixis continues to generate robust cash flow, funding both the pipeline and repurchases. In the second quarter, the company repurchased $312 million of stock, leaving $598 million under the current authorization. Chris Senner, in an earlier call, noted the commitment: “we have $590 million left over on the most recent authorization $750 million from the board, and our commitment is to complete that this year.” — Christopher Senner, Chief Financial Officer · 2026-02-10 Dana Aftab echoed the pipeline focus in May: “we are expecting results in the second half of the year.” — Dana T. Aftab, Executive Vice President · 2026-05-05 These quotes highlight that the guidance cut does not reflect a strategic shift.
Fundamentally, the company remains profitable and growing. Total revenue reached $611M in Q1 2026, up 10% year-over-year, with a stable gross margin above 96%. The reduction in R&D expense guidance, while modest, indicates a commitment to efficiency even as zanza's pivotal program accelerates. The stock’s 90-day return of +22% suggests the market is looking through the near-term guidance to the upcoming catalysts, particularly the STELLAR-303 PDUFA and the STELLAR-304 readout.
In summary, the slower NET ramp is a speed bump, not a derailment. Exelixis is balancing near-term revenue adjustments with a pipeline that could transform the company. The recent stock strength indicates investors are focused on the zanza story, and the company’s disciplined capital allocation provides a strong foundation for execution.