EXEL leadership update: Dr. Dana Aftab promoted; Dr. Amy Peterson exits with severance

Rhea-AI Filing Summary

On August 29, 2025, Exelixis, Inc. announced an internal leadership change: Dana T. Aftab, Ph.D., currently the company’s Executive Vice President, Discovery and Translational Research and Chief Scientific Officer, was appointed Executive Vice President, Research and Development. The filing states information about Dr. Aftab’s background, compensation arrangements, and any related-party transactions is incorporated by reference from the company’s definitive proxy statement on Schedule 14A filed April 16, 2025. Effective the same day, Amy C. Peterson, M.D., concluded her service as Executive Vice President, Product Development and Medical Affairs and Chief Medical Officer, and is entitled to payments under the company’s Change in Control and Severance Benefit Plan, as amended, and applicable law.

Positive

• Leadership continuity through an internal promotion of Dana T. Aftab, Ph.D., which preserves institutional knowledge in R&D
• Consistent disclosure by incorporating background and compensation details from the company’s April 16, 2025 Schedule 14A proxy statement

Negative

• Departure of the Chief Medical Officer, Amy C. Peterson, which removes an established medical affairs leader from the executive team
• Severance payments to the departing CMO under the Change in Control and Severance Benefit Plan are required, though amounts are not disclosed in this filing

Insights

Corporate Governance Expert

TL;DR: Routine executive succession with internal promotion and a departing C-suite officer receiving contractual severance protections.

The appointment of Dr. Aftab from an existing senior scientific role to head R&D signals continuity in leadership rather than an external strategic shift, and the disclosure references prior proxy filing details for background and compensation, preserving disclosure consistency. The departure of the Chief Medical Officer, Amy Peterson, triggers contractual severance under the company’s Change in Control and Severance Benefit Plan, which the company explicitly notes without quantifying amounts in this filing.

R&D/Clinical Development Analyst

TL;DR: Internal promotion likely sustains ongoing research programs; CMO departure noted but specifics of clinical impact are not disclosed.

Promoting the existing Chief Scientific Officer to lead Research and Development suggests management intends to keep scientific strategy intact. The filing does not disclose any program-level changes, clinical delays, or personnel impacts beyond the executive transition. No financial amounts or operational effects on development programs are provided; background and compensation details are deferred to the April 16, 2025 proxy statement.

August 29, 20250000939767false00009397672025-08-292025-08-29

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): August 29, 2025

EXELIXIS, INC.

(Exact name of registrant as specified in its charter)

Delaware			000-30235			04-3257395
(State or Other Jurisdiction of Incorporation)			(Commission File Number)			(IRS Employer Identification No.)

1851 Harbor Bay Parkway

Alameda, California 94502

(Address of principal executive offices) (Zip Code)

(650) 837-7000

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class			Trading Symbol(s)			Name of each exchange on which registered
Common Stock $0.001 Par Value per Share			EXEL			The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On August 29, 2025, the Board of Directors (the “Board”) of Exelixis, Inc. (the “Company”) appointed Dana T. Aftab, Ph.D., the Company’s current Executive Vice President, Discovery and Translational Research and Chief Scientific Officer as Executive Vice President, Research and Development.

Information regarding Dr. Aftab’s background and business experience, any contracts and compensatory arrangements between the Company and Dr. Aftab, and any related party transactions involving Dr. Aftab is incorporated by reference herein from the Company’s definitive proxy statement on Schedule 14A filed with the Securities and Exchange Commission on April 16, 2025.

Effective August 29, 2025, Amy C. Peterson, M.D., has concluded her service as Executive Vice President, Product Development and Medical Affairs and Chief Medical Officer of the Company. In connection with her departure from the Company, Dr. Peterson is entitled to payments in accordance with the Company’s Change in Control and Severance Benefit Plan, as amended and restated, and applicable law.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

									EXELIXIS, INC.
August 29, 2025									/s/ Jeffrey J. Hessekiel
Date									Jeffrey J. Hessekiel
									Executive Vice President and General Counsel

FAQ

What executive changes did Exelixis (EXEL) announce on August 29, 2025?

The company appointed Dana T. Aftab, Ph.D. as Executive Vice President, Research and Development, and Amy C. Peterson, M.D. concluded her service as Executive Vice President, Product Development and Medical Affairs and Chief Medical Officer.

When did the leadership changes at Exelixis take effect?

Both the appointment of Dr. Dana T. Aftab and the conclusion of Dr. Amy C. Peterson’s service are effective August 29, 2025.

Where can I find details about Dr. Aftab’s background and compensation?

The filing incorporates those details by reference from Exelixis’s definitive proxy statement on Schedule 14A filed April 16, 2025.

Will Amy Peterson receive any payments upon departure?

Yes. The filing states Dr. Peterson is entitled to payments under the company’s Change in Control and Severance Benefit Plan, as amended, and applicable law; no payment amounts are disclosed here.

Does the filing disclose financial impacts from these executive changes?

No. This 8-K does not quantify any financial impact or provide specific severance amounts; it references the proxy statement for compensation details.