6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OFFOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 or15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of April, 2023

Commission File Number: 001-38452

MEREO BIOPHARMA GROUP PLC

(Translation of registrant’s name into English)

4^th^ Floor, One Cavendish Place,

London, W1G 0QF, United Kingdom

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of 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):  ☐

MEREO BIOPHARMA GROUP PLC

(the “Company”)

Notice of Annual General Meeting

The Company announces that the 2023 Annual General Meeting (“AGM”) will be held at 5th Floor, One Cavendish Place, London W1G 0QF, United Kingdom on May 22, 2023 at 2.00 p.m. (London time). The Notice of AGM is available on the Company’s website, www.mereobiopharma.com/agm2023

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.

Date: April 12, 2023