Form 8-K

8-K — Summit Therapeutics Inc.

Accession: 0001599298-26-000054

Filed: 2026-06-12

Period: 2026-06-10

CIK: 0001599298

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Submission of Matters to a Vote of Security Holders

Documents

8-K — smmt-20260610.htm (Primary)

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8-K

8-K (Primary)

Filename: smmt-20260610.htm · Sequence: 1

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0001599298FALSE00015992982026-06-102026-06-10

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): June 10, 2026

Summit Therapeutics Inc.

(Exact Name of Registrant as Specified in Its Charter)

Delaware 001-36866 37-1979717

(State or Other Jurisdiction

of Incorporation) (Commission

File Number) (IRS Employer

Identification No.)

601 Brickell Key Drive, Suite 1000, Miami, FL

33131

(Address of Principal Executive Offices) (Zip Code)

Registrant’s Telephone Number, Including Area Code: (305) 203-2034

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 (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, $0.01 par value per share SMMT 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 5.07

Submission of Matters to a Vote of Security Holders.

On June 10, 2026, Summit Therapeutics Inc. (the “Company”) held its 2026 Annual Meeting of Stockholders (the “Annual Meeting”). The following matters were submitted to a vote of the Company’s stockholders at the Annual Meeting: (i) the election of nine directors to serve until the Company’s 2027 Annual Meeting of Stockholders and until their successors are duly elected and qualified; (ii) the ratification of the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2026; (iii) a non-binding advisory vote to approve the compensation paid to the Company’s named executive officers, and (iv) the approval of an amendment to the Summit Therapeutics Inc. 2020 Stock Incentive Plan (the “Plan”) to increase the number of shares of the Company’s common stock issuable under the Plan by 8,000,000 shares.

Each of the matters submitted to a vote of the Company’s stockholders at the Annual Meeting was approved by the requisite vote of the Company’s stockholders in accordance with the recommendation of the Company’s Board of Directors. Set forth below is the number of votes cast for, against or withheld, as well as the number of abstentions and broker non-votes, as to each such matter, including a separate tabulation with respect to each nominee for director, as applicable:

Proposal 1

Election of Directors

Director Nominees

For

Withheld

Broker Non-Votes

Robert W. Duggan

636,409,964 10,761,538 30,576,341

Mahkam Zanganeh

637,405,433 9,766,069 30,576,341

Manmeet Soni

636,690,652 10,480,850 30,576,341

Kenneth A. Clark

622,127,920 25,043,582 30,576,341

Robert Booth

646,257,923 913,579 30,576,341

Alessandra Cesano

646,263,718 907,784 30,576,341

Yu (Michelle) Xia

636,028,876 11,142,626 30,576,341

Mostafa Ronaghi

646,570,238 601,264 30,576,341

Jeff Huber

646,659,701 511,801 30,576,341

Proposal 2

For

Against

Abstain

Broker Non-Votes

Ratification of the appointment of PricewaterhouseCoopers LLP for the fiscal year ending December 31, 2026

677,302,337 85,284 360,222

—

Proposal 3

For

Against

Abstain

Broker Non-Votes

Non-binding advisory vote to approve the compensation of named executive officers

622,624,328 24,445,791 101,383 30,576,341

Proposal 4

For

Against

Abstain

Broker Non-Votes

Approval of an amendment to the Plan to increase the number of shares of the Company's common stock issuable under the Plan by 8,000,000 shares

619,799,393 27,247,910 124,199 30,576,341

SIGNATURE

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.

SUMMIT THERAPEUTICS INC.

Date: June 12, 2026 By: /s/ Manmeet S. Soni

Chief Operating Officer, Chief Financial Officer and Director

(Principal Financial Officer)

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Entity Address, Address Line One

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