# EDGAR Filing Document

**Accession Number:** 0001599298
**File Stem:** 0001599298-26-000033
**Filing Date:** 2026-4
**Character Count:** 2781
**Document Hash:** f1b982d6db7b3a1cbd392baa95e44684
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001599298-26-000033.hdr.sgml**: 20260417

**ACCESSION NUMBER**: 0001599298-26-000033

**CONFORMED SUBMISSION TYPE**: DEFA14A

**PUBLIC DOCUMENT COUNT**: 11

**FILED AS OF DATE**: 20260417

**DATE AS OF CHANGE**: 20260417

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Summit Therapeutics Inc.
- **CENTRAL INDEX KEY:** 0001599298
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 371979717
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** DEFA14A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-36866
- **FILM NUMBER:** 26872457

**BUSINESS ADDRESS:**
- **STREET 1:** 601 BRICKELL KEY DRIVE
- **STREET 2:** SUITE 1000
- **CITY:** MIAMI
- **STATE:** FL
- **ZIP:** 33131
- **BUSINESS PHONE:** 305-203-2034

**MAIL ADDRESS:**
- **STREET 1:** 601 BRICKELL KEY DRIVE
- **STREET 2:** SUITE 1000
- **CITY:** MIAMI
- **STATE:** FL
- **ZIP:** 33131

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Summit Therapeutics plc
- **DATE OF NAME CHANGE:** 20150219

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Summit Corp plc
- **DATE OF NAME CHANGE:** 20140205

?xml version='1.0' encoding='ASCII'? smmt-20260417

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**SCHEDULE 14A**

(Rule 14a-101)

Information Required in Proxy Statement

Schedule 14a Information

Proxy Statement Pursuant to Section 14(a) of The Securities Exchange Act of 1934

(Amendment No.)

Filed by the Registrant&nbsp;&nbsp;&nbsp;&nbsp;☒

Filed by a Party other than the Registrant&nbsp;&nbsp;&nbsp;&nbsp;☐

Check the appropriate box:

&nbsp;&nbsp;&nbsp;&nbsp;☐&nbsp;&nbsp;&nbsp;&nbsp;Preliminary Proxy Statement

&nbsp;&nbsp;&nbsp;&nbsp;☐&nbsp;&nbsp;&nbsp;&nbsp;Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

&nbsp;&nbsp;&nbsp;&nbsp;☐ &nbsp;&nbsp;&nbsp;&nbsp;Definitive Proxy Statement

&nbsp;&nbsp;&nbsp;&nbsp;☒&nbsp;&nbsp;&nbsp;&nbsp;Definitive Additional Materials

&nbsp;&nbsp;&nbsp;&nbsp;☐&nbsp;&nbsp;&nbsp;&nbsp;Soliciting Material Under Rule 14a-12

---

| |
|:---|
| **SUMMIT THERAPEUTICS INC.** |
| (Name of Registrant as Specified in Its Charter) |
| (Name of Persons(s) Filing Proxy Statement, if Other Than the Registrant) |

---

Payment of Filing Fee (Check the appropriate box):

&nbsp;&nbsp;&nbsp;&nbsp;☒ &nbsp;&nbsp;&nbsp;&nbsp;No fee required.

☐&nbsp;&nbsp;&nbsp;&nbsp;Fee paid previously with preliminary materials.

&nbsp;&nbsp;&nbsp;&nbsp;☐&nbsp;&nbsp;&nbsp;&nbsp;Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

&nbsp;&nbsp;&nbsp;&nbsp;

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![Notice.jpg](smmt-20260417_g1.jpg)

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![Notice 2.jpg](smmt-20260417_g2.jpg)