NuCana furnishes 6-K on NUC-3373 data in medRxiv and PLOS ONE

Rhea-AI Filing Summary

NuCana plc reported an update via Form 6-K, stating that on October 14, 2025 it announced the publication of new data from the NuTide:303 clinical study evaluating NUC-3373 on medRxiv, alongside complementary preclinical findings published in the peer‑reviewed journal PLOS ONE.

The company furnished a press release as Exhibit 99.1. The information is being furnished, not filed, under the Exchange Act and is not subject to Section 18 liabilities, nor incorporated into other filings except by specific reference.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGE ACT OF 1934

For the month of October 2025

(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 reports under cover Form 20-F or Form 40-F.

Form 20-F ☒   Form 40-F ☐

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

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

Other Events

On October 14, 2025, NuCana plc (the “Company”) issued a press release announcing the publication of new data from the NuTide:303 clinical study of NUC-3373 in medRxiv, the preprint server for health sciences, together with complementary preclinical findings published in the peer-reviewed journal Public Library of Science ONE (PLOS ONE). 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 October 14, 2025

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/ Ian Webster
Name:		Ian Webster
Title:		Interim Chief Financial Officer
		(Principal Financial and Accounting Officer)

Date: October 14, 2025

FAQ

What did NuCana (NCNA) announce in this 6-K?

NuCana announced publication of new data from the NuTide:303 clinical study of NUC-3373 on medRxiv, plus complementary preclinical findings in PLOS ONE.

Where were the NUC-3373 findings published?

Clinical study data were posted on medRxiv, and complementary preclinical findings were published in the peer-reviewed journal PLOS ONE.

Which study and drug are referenced by NuCana (NCNA)?

The NuTide:303 clinical study and the investigational drug NUC-3373.

What is included as Exhibit 99.1?

A press release dated October 14, 2025.

Is the information considered filed or furnished?

It is being furnished, not filed, and is not subject to Section 18 liabilities or incorporated by reference unless expressly stated.

When did NuCana issue the press release?

October 14, 2025.