THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION. If you are in any doubt as to any aspect of the proposals referred to in this notice or as to the action you should take, please take advice from a stockb

THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION.

If you are in any doubt as to any aspect of the proposals referred to in this notice or as to the action you should take, please take advice from a

stockbroker, solicitor, accountant or other independent professional adviser.

If you have sold or otherwise transferred all of your ordinary shares

in the capital of the Company ( Ordinary Shares ), please send this document, together with the enclosed documents, at once to the purchaser or transferee, or to the stockbroker, bank or other agent through whom the sale or transfer

was effected for transmission to the purchaser or transferee.

It is important that you submit your proxy vote electronically. Proxies may be

submitted electronically using Link Group s Signal Shares share portal service at www.signalshares.com or in hard copy form if you request a hard copy Form of Proxy from the Company s registrar, Link Group. In order to be valid, proxy

appointments must be submitted using Link Group s Signal Shares share portal service or in hard copy form to Link Group at PXS 1, Central Square, 29 Wellington Street, Leeds LS1 4DL, in each case, so as to be received by no later than 2.00 p.m.

(UK Time) on 14 December 2023 or 48 hours before any adjourned meeting. The electronic appointment of a proxy using Link Group s Signal Shares share portal service or the completion and return of a Form of Proxy in hard copy form will not

preclude shareholders from attending and voting at the General Meeting should they so wish. Any hard copy Form of Proxy should, to be valid, be completed and signed in accordance with the instructions printed on it.

If you require a hard copy Form of Proxy (or assistance with how to complete, sign and return it) or assistance in submitting your proxy appointment

electronically, please call Link Group s portal team on +44 (0)371 664 0391. Calls are charged at the standard geographic rate and will vary by provider. Calls from outside the UK will be charged at the applicable international rate. Lines are

open 9.00 a.m. to 5.30 p.m. (UK Time), Monday to Friday, excluding public holidays in England and Wales.

If you hold your Ordinary Shares in

uncertificated form (i.e. in CREST), you may appoint a proxy for the General Meeting by completing and transmitting a CREST Proxy Instruction in accordance with the procedures set out in the CREST Manual issued by Euroclear so that it is received by

the registrar (under CREST Participation ID RA10) by no later than 2.00 p.m. (UK Time) on 14 December 2023. The time of receipt will be taken to be the time from which the registrar is able to retrieve the message by enquiry to CREST in the

manner proscribed by CREST.

A copy of this document will also be available on the Company s website, https://www.mereobiopharma.com/gm2023

NOTICE OF THE GENERAL MEETING OF

MEREO BIOPHARMA GROUP PLC

to be held at the 5th Floor, One Cavendish Place, London W1G 0QF, United Kingdom

on 18 December 2023 at 2.00 p.m. (UK Time)

Cautionary note regarding forward-looking

This document contains statements about the Company that are or may be forward-looking statements . We intend such

forward-looking statements to be covered by the safe harbour provisions for forward-looking statements contained in Section 27A of the U.S. Securities Act of 1933, as amended, and Section 21E of the U.S. Securities Exchange Act of 1934, as

amended. All statements, other than statements of historical facts, included in this document, including, without limitation, statements regarding our status as a foreign private issuer and the consequences of losing such status are

forward-looking statements. The words targets , plans , believes , expects , aims , intends , will , may , should , anticipates ,

estimates , projects or words or terms of similar substance, or the negative thereof, are intended to identify forward-looking statements, though not all forward-looking statements use these words or expressions. These

forward-looking statements are not guarantees of future performance. These forward-looking statements involve known and unknown risks, uncertainties and other factors that could cause the actual results, performance or achievements of any such

person, or industry results, to differ materially from any results, performance

or achievements expressed or implied by such forward-looking statements, including, but not limited to:

we expect to lose our foreign private issuer status in the future which could result in significant additional costs and expenses. These and other important factors are discussed in the Risk Factors section of the Company s annual

reports and accounts and filings that the Company makes with the Securities and Exchange Commission, including its Annual Report on Form 20-F for the year ended 31 December 2022 and subsequent reports

furnished on Form 6-K. These forward-looking statements are based on numerous assumptions regarding the present and future business strategies of such persons and the environment in which each will operate in

the future. Past performance is not a guarantee of future performance. Investors should not place undue reliance on such forward-looking statements and, save as is required by law or regulation, the Company does not undertake any obligation to

update publicly or revise any forward-looking statements (including to reflect any change in expectations with regard thereto or any change in events, conditions or circumstances on which any such statement is based). All subsequent forward-looking

statements attributed to the Company or any persons acting on its behalf are expressly qualified in their entirety by the cautionary statement above. All forward-looking statements contained in this document are based on information available to the

Company at the date of this document, unless some other time is specified in relation to them, and the posting or receipt of this document shall not give rise to any implication that there has been no change in the facts set forth herein since such

Notice to overseas persons

distribution of this document in certain jurisdictions may be restricted by law and therefore persons into whose possession this document comes should inform themselves about and observe any such restrictions. Any failure to comply with these

restrictions may constitute a violation of the securities laws of any such jurisdiction.

The definitions set out below apply throughout this document, unless the context requires otherwise:

LETTER FROM THE CHAIRMAN OF MEREO BIOPHARMA GROUP PLC

(registered and incorporated in England and Wales with Company number 09481161)

Notice of General Meeting

The purpose of this document is to provide you with details of the General Meeting of the Company to be held on 18 December 2023 at 2.00 p.m. (UK

Time) and convened by the formal Notice of General Meeting set out on page 7 of this document.

This letter also explains the background to and

reasons for the resolution which will be proposed at the General Meeting (the Resolution ), why the Directors consider the Resolution to be in the best interests of shareholders of the Company as a whole and why they unanimously

recommend that Shareholders vote in favour of the Resolution.

The Company currently qualifies as a foreign private issuer under the Exchange Act. As a foreign private issuer , the Company

relies on certain home country governance practices rather than the corporate governance requirements of Nasdaq applicable to U.S. domestic companies, as is permitted by the listing requirements of Nasdaq.

With effect from 1 January 2024, the Company will no longer qualify for foreign private issuer status and it will therefore be subject

to, amongst other rules and requirements, the Nasdaq listing requirements applicable to U.S. domestic companies, including, but not limited to, requirements with respect to the composition of the board of directors and committees, certain corporate

governance matters and shareholder approval of certain actions.

The Board is committed to ensuring that the Company will be in compliance with all

applicable additional rules and requirements as of 1 January 2024 and the Company, together with its advisers, have therefore undertaken a detailed review of its existing governance arrangements in order to identify and implement any required

As part of this review, it has been identified that, in order to comply with Nasdaq Listing Rule

5620(c), the Articles of Association must be amended so as to specify that the quorum for any meeting of the Shareholders shall not be less than 33 1/3 per cent. of the issued and outstanding Ordinary Shares (the Articles

The Resolution gives effect to the Articles Amendment and is proposed as a special resolution, requiring the approval of the

Shareholders at the General Meeting by a majority of not less than 75 per cent.

Approval by Shareholders of the Resolution will ensure that

the Company is in compliance with the Nasdaq listing rules pertaining to Shareholder meeting quorum requirements as of 1 January 2024. Therefore, the Directors consider the Resolution to be in the best interests of Shareholders of the Company

as a whole and unanimously recommend that you vote in favour of the Resolution.

Please submit your vote by proxy electronically using Link Group s Signal Shares share portal service at www.signalshares.com or in hard copy form

if you request a hard copy Form of Proxy from the Company s registrar, Link Group. In order to be valid, proxy appointments must be submitted using Link Group s Signal Shares share portal service or in hard copy form to Link Group at PXS

1, Central Square, 29 Wellington Street, Leeds LS1 4DL, in each case, so as to be received by no later than 2.00 p.m. (UK Time) on 14 December 2023 or 48 hours before any adjourned meeting.

If you require a hard copy Form of Proxy (or assistance with how to complete, sign and return it) or assistance in submitting your proxy appointment

electronically, please call Link Group s portal team on +44 (0) 71 664 0391. Calls are charged at the standard geographic rate and will vary by provider. Calls from outside the UK will be charged at the applicable

international rate. Lines are open 9.00 a.m. to 5.30 p.m., Monday to Friday, excluding public holidays in England and Wales.

Ordinary Shares in uncertificated form (i.e. in CREST), you may appoint a proxy for the General Meeting by completing and transmitting a CREST Proxy Instruction in accordance with the procedures set out in the CREST Manual issued by Euroclear so

that it is received by the registrar (under CREST Participation ID RA10) by no later than 2.00 p.m. (UK Time) on 14 December 2023 or 48 hours before any adjourned meeting. The time of receipt will be taken to be the time from which the

registrar is able to retrieve the message by enquiry to CREST in the manner proscribed by CREST.

The appointment of a proxy will not preclude you

from attending the General Meeting and voting in person if you so wish.

The Directors consider that the Resolution to be proposed at the General Meeting is in the best interests of the Company and its shareholders as a

whole and is likely to promote the success of the Company. The Directors unanimously recommend that you vote IN FAVOUR of the proposed Resolution, as they intend to do in respect of their own beneficial shareholdings.

MEREO BIOPHARMA GROUP PLC

incorporated in England and Wales with company number 09481161)

NOTICE OF GENERAL MEETING

NOTICE IS HEREBY GIVEN that a General Meeting of the Company will be held at 5th Floor, One Cavendish Place, London W1G 0QF, United Kingdom on

18 December 2023 at 2.00 p.m. (UK Time) to consider and, if thought fit, pass the following resolution as a special resolution.

Notice of General Meeting Notes:

Entitlement to Attend and Vote

Appointment of Proxies

Appointment of Proxy Using Hard Copy Proxy Form

Appointment of a Proxy Online

Appointment of Proxies Through CREST

Appointment of Proxies via Proxymity

Appointment of Proxy by Joint Members

Changing Proxy Instructions

Termination of Proxy

Corporate Representatives

MEREO BIOPHARMA GROUP PLC