NuCana (NCNA) 6-K Current report (foreign)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN ISSUER

PURSUANTTO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGE ACT OF 1934

For the month of November 2018

(Commission File No. 001-38215)

NUCANA PLC

(Translation of registrant’s name into English)

3 Lochside Way

Edinburgh EH12 9DT

United Kingdom

(Address of registrant’s principal executive office)

Indicate by check mark whether the registrant files or will file annual reportsunder cover Form 20-F or Form 40-F.

Form 20-F ☒                Form 40-F ☐

Indicate by check mark if the registrant issubmitting the Form 6-K in paper as permittedby Regulation S-T Rule 101 (b) (1): ☐

Indicate by check mark if the registrant issubmitting the Form 6-K in paper as permittedby Regulation S-T Rule 101 (b) (7): ☐

Other Events

On November 1, 2018, NuCana plc (the “Company”) issued a press release announcing that the first patients have been enrolled in the Phase 1b study ofNUC-3373 in advanced colorectal cancer. The press release is attached as Exhibit 99.1 hereto and is incorporated by reference herein.

The information in the attached Exhibit 99.1 is being furnished and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed incorporated by reference in any filing made by the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as otherwise set forth herein or as shall be expressly set forth by specific reference in such a filing.

Exhibits

99.1 Press Release dated November 1, 2018

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, thereunto duly authorized.

NuCana plc
By:	/s/ Donald Munoz
Name: Title:	Donald Munoz Chief Financial Officer

Date: November 1, 2018