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Form 8-K

sec.gov

8-K — Annexon, Inc.

Accession: 0001193125-26-342524

Filed: 2026-08-10

Period: 2026-08-10

CIK: 0001528115

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

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

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — d130710d8k.htm (Primary)

EX-99.1 (d130710dex991.htm)

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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 10, 2026

ANNEXON, INC.

(Exact name of registrant as specified in its charter)

Delaware

001-39402

27-5414423

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

1400 Sierra Point Parkway, Bldg C, Suite 200

Brisbane, California 94005

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (650) 822-5500

Not Applicable

(Former name or former address, if changed since last report)

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:

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, par value $0.001 per share

ANNX

The Nasdaq Stock Market

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.

(b) Director Resignation

On August 10, 2026, Muneer Satter, a member of the board of directors (the “Board”) of Annexon, Inc. (the “Company”), notified the Company of his resignation as a member of the Board and as a member of the audit committee of the Board (the “Audit Committee”) and as chair of the nominating and corporate governance committee of the Board (the “Nominating Committee”), effective immediately prior to the appointment of a replacement director, Mark S. Blumenkranz, M.D., M.S.S., to the Board. The Company’s management and the Board thank Mr. Satter for his more than eleven years of distinguished service on the Board and many positive contributions to the Company.

Mr. Satter’s resignation was not the result of any disagreement with the Company on any matter related to the Company’s operations, policies, practices or strategy, the Company’s management or the Board.

(d) Director Appointment

On August 10, 2026, the Board, based on the recommendation of the Nominating Committee, appointed Mark S. Blumenkranz, M.D., M.S.S., to the Board, effective immediately (the “Effective Date”). Dr. Blumenkranz will serve as a Class II director with a term expiring at the 2028 annual meeting of stockholders and until his successor has been elected and qualified. Dr. Blumenkranz was also appointed as a member of the Audit Committee and Science and Technology committee of the Board.

Pursuant to the Company’s non-employee director compensation program (the “NEDC Program”), as a non-employee director, Dr. Blumenkranz will receive (i) a $40,000 annual retainer for his service on the Board, and (ii) on the date of each annual stockholder meeting, an automatic grant of a stock option to purchase 65,000 shares of common stock under the Company’s 2020 Incentive Award Plan (the “2020 Plan”), which vests on the earlier of the first anniversary of the date of grant or the date of the next annual stockholder’s meeting. On the Effective Date, and in lieu of the automatic initial stock option grant set forth in the Company’s NEDC Program, Dr. Blumenkranz was also granted a stock option to purchase 175,000 shares of common stock under the 2020 Plan.

In addition, Dr. Blumenkranz has entered into the Company’s standard indemnification and advancement agreement for directors and executive officers, the form of which was filed as Exhibit 10.10 to the Company’s Annual Report on Form 10-K, filed with the Securities and Exchange Commission (“SEC”) on March 30, 2026. There is no arrangement or understanding between Dr. Blumenkranz and any other person pursuant to which he was selected as a director, and there is no family relationship between Dr. Blumenkranz and any of the Company’s other directors or executive officers. The Company is not aware of any transaction involving Dr. Blumenkranz requiring disclosure under Item 404(a) of Regulation S-K.

Item 7.01

Regulation FD Disclosure.

On August 10, 2026, the Company issued a press release announcing the resignation of Mr. Satter from the Board and the appointment of Dr. Blumenkranz to the Board. A copy of the press release is filed herewith as Exhibit 99.1 and is incorporated herein by reference.

The information furnished under this Item 7.01 (including Exhibit 99.1), shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information in this Item 7.01 (including Exhibit 99.1) shall not be deemed incorporated by reference into any filing with the SEC made by the Company, whether made before or after the date hereof, regardless of any general incorporation language in such filing, except as expressly set forth by specific reference in such filing.

Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

No.

Description

99.1

Press release, dated August 10, 2026, titled “Annexon Appoints Renowned Retinal Surgeon and Biotechnology Entrepreneur Mark S. Blumenkranz, M.D., M.M.S. to its Board of Directors”.

104.1

Cover Page Interactive Data File, formatted in inline XBRL.

SIGNATURES

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

Dated: August 10, 2026

Annexon, Inc.

By:

/s/ Jennifer Lew

Jennifer Lew

Executive Vice President and Chief Financial Officer

EX-99.1

EX-99.1

Filename: d130710dex991.htm · Sequence: 2

EX-99.1

Exhibit 99.1

Annexon Appoints Renowned Retinal Surgeon and Biotechnology Entrepreneur Mark S. Blumenkranz, M.D.,

M.M.S. to its

Board of Directors

Over Four Decades of Clinical, Scientific and Corporate Leadership Advancing Innovation in Retinal Disease

BRISBANE, Calif., August 10, 2026 – Annexon, Inc. (Nasdaq: ANNX), a biopharmaceutical company advancing the next

generation platform of targeted immunotherapies for multiple neuroinflammatory diseases that impact nearly 10 million people worldwide, today announced the appointment of Mark S. Blumenkranz, M.D., M.M.S., to its board of directors.

Dr. Blumenkranz, a renowned retinal surgeon and biotechnology entrepreneur, brings more than four decades of clinical, scientific and corporate leadership experience advancing innovative therapies for retinal disease. The Company also announced

that Muneer Satter will step down from the board after more than 11 years of distinguished service and steadfast support as a director and investor.

“We are delighted to welcome Mark to our board of directors as Annexon enters its next phase of growth, advancing two late-stage clinical programs with

potential to help millions of patients worldwide,” said Douglas Love, president and chief executive officer of Annexon. “Mark’s unique combination of retinal expertise, biotechnology leadership, and experience building successful

companies will provide tremendous strategic value as we advance vonaprument in geographic atrophy and prepare for commercialization.

Mr. Love

continued, “We are also deeply grateful to Muneer for his many years of service, strategic guidance and unwavering support since joining our Board in 2015. As a trusted advisor and investor with strong conviction in our platform, Muneer played

an instrumental role in the company’s evolution from a preclinical stage organization into a public biotechnology company clinically advancing a robust late-stage pipeline for neuroinflammatory diseases. We thank Muneer for his many

contributions and wish him continued success in his future endeavors.”

Dr. Blumenkranz added, “Annexon’s C1q-targeted platform approach is uniquely positioned to help patients across a range of neuroinflammatory diseases and importantly, represents a differentiated path forward for patients with geographic atrophy, a

disease that has lacked a truly vision-sparing treatment option. I look forward to working with the board and the management team as vonaprument advances toward pivotal Phase 3 data and potential registration.”

Mark S. Blumenkranz, M.D., M.M.S., is the H.J. Smead Professor Emeritus of Ophthalmology at Stanford University School of Medicine and Co-Director of Stanford’s Ophthalmic Innovation Program. An internationally recognized retinal specialist, surgeon, entrepreneur and innovator, Dr. Blumenkranz previously served as Chair of

Stanford’s Department of Ophthalmology and founding Director of the Byers Eye Institute at Stanford. Throughout his distinguished career, he has helped pioneer advances in retinal surgery, drug delivery, ophthalmic imaging and gene therapy,

while authoring more than 175 peer-reviewed publications and holding numerous patents. He has co-founded and led numerous ophthalmic and life sciences companies through development, commercialization and

successful acquisition, including Adverum Biotechnologies, where he served as co-founder and chairman of the board; Optimedica Corporation, which was acquired by Abbott Medical Optics; Oculeve, which was

acquired by Allergan; and Kedalion Therapeutics, where he served as founding chairman and chief executive officer until its acquisition by Novartis. He was also a founder and director of Verana Health. Dr. Blumenkranz currently serves as

Managing Director of Lagunita Biosciences and sits on the boards of several ophthalmic and life sciences companies. He received his undergraduate degree, master’s degree in biochemical pharmacology, and M.D. from Brown University, completed

his ophthalmology residency at Stanford University, and a fellowship in vitreoretinal diseases at the Bascom Palmer Eye Institute.

About Annexon

Annexon Biosciences (Nasdaq: ANNX) is advancing the next generation platform of targeted immunotherapies for nearly 10 million people worldwide

living with serious neuroinflammatory diseases. Our founding scientific approach focuses on C1q, the initiating molecule of a potent inflammatory pathway that when misdirected can lead to tissue damage and loss of function in a host of diseases. Our

targeted therapies are designed to stop classical complement-driven neuroinflammation at its source to provide meaningful functional benefit and alter the course of disease. Annexon’s mission is to deliver game-changing therapies to patients

so that they can live their best lives. To learn more visit annexonbio.com.

Forward Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E

of the Securities Exchange Act of 1934, as amended. In some cases, you can identify forward-looking statements by terminology such as “aim,” “anticipate,” “assume,” “believe,”

“contemplate,” “continue,” “could,” “design,” “due,” “estimate,” “expect,” “goal,” “intend,” “may,” “objective,”

“plan,” “positioned,” “potential,” “predict,” “seek,” “should,” “target,” “will,”

“would” and other similar expressions that are predictions of or indicate future events and future trends, or the negative of these terms or other comparable terminology. All

statements other than statements of historical facts contained in this press release are forward-looking statements. These forward-looking statements include, but are not limited to, statements about: the company’s ability to advance

vonaprument in geographic atrophy and prepare for commercialization, if approved; the benefit of the company’s C1q-targeted platform and its ability to help patients across a range of neuroinflammatory

diseases; and continuing advancement of the company’s portfolio. Forward-looking statements are not guarantees of future performance and are subject to risks and uncertainties that could cause actual results and events to differ materially

from those anticipated, including, but not limited to, risks and uncertainties related to: the company’s history of net operating losses; the company’s ability to obtain necessary capital to fund its clinical programs; the early stages

of clinical development of the company’s product candidates; the effects of public health crises on the company’s clinical programs and business operations; the company’s ability to obtain regulatory approval of and successfully

commercialize its product candidates; any undesirable side effects or other properties of the company’s product candidates; the company’s reliance on third-party suppliers and manufacturers; the outcomes of any future collaboration

agreements; and the company’s ability to adequately maintain intellectual property rights for its product candidates. These and other risks are described in greater detail under the section titled “Risk Factors” contained in the

company’s Annual Report on Form 10-K and Quarterly Reports on Form 10-Q and the company’s other filings with the SEC. Any forward-looking statements that the

company makes in this press release are made pursuant to the Private Securities Litigation Reform Act of 1995, as amended, and speak only as of the date of this press release. Except as required by law, the company undertakes no obligation to

publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.

Investor Contact:

Joyce Allaire

LifeSci Advisors

jallaire@lifesciadvisors.com

Media Contact:

Beth Keshishian

917-912-7195

beth@bethkeshishian.com

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