Summit Therapeutics Inc. — Director's Dealing 2025

Oct 23, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Summit Therapeutics Inc. (SMMT)
CIK: 0001599298
Period of Report: 2025-10-21

Reporting Person: DUGGAN ROBERT W (Director, Co-Chief Executive Officer, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-10-21	Common Stock	A	13980789	$18.74	Acquired	570073879	Direct
2025-10-21	Common Stock	A	266808	$18.74	Acquired	25724474	Indirect
2025-10-21	Common Stock	P	26680	$18.74	Acquired	76680	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	31000	Indirect
Common Stock	10199776	Indirect

Footnotes

F1: Acquired in a private placement transaction pursuant to the terms of a definitive agreement, dated as of October 21, 2025, pursuant to which the Issuer agreed to sell shares of common stock to the Reporting Person and certain other parties at a purchase price of $18.74 per share. The transaction is anticipated to close on or about October 23, 2025.

F2: The Reporting Person disclaims beneficial ownership of these securities, except to the extent of his pecuniary interest therein, if any, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of all of the reported securities for purposes of Section 16 or for any other purpose.