Hemogenyx Pharmaceuticals : AGM Notice (2022 AGM)

THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION

If you are in any doubt about the contents of this document or the action you should take, you should immediately consult your stockbroker, bank manager, solicitor, accountant, or other independent financial adviser duly authorised under the Financial Services and Markets Act 2000, if you are resident in the United Kingdom, or if not, another appropriately authorised independent adviser.

If you have sold or otherwise transferred all of your holdings of ordinary shares of £0.01 (1 pence) each (the "Ordinary Shares") in the capital of Hemogenyx Pharmaceuticals plc ("Hemogenyx Pharmaceuticals" or the "Company"), you should immediately forward this document together with the enclosed documents as soon as possible to the purchaser or transferee or to the bank, stockbroker or other agent through whom the sale or transfer was effected for transmission to the purchaser or transferee. If you have sold or otherwise transferred some of your Ordinary Shares, you should contact the bank, stockbroker or other agent through whom the sale or transfer was effected.

The Company's registered office is 5 Fleet Place, London, EC4M 7RD, United Kingdom. Tel: [phone]. The Company is incorporated and registered in

England and Wales under the Companies Act 2006, with company number 08401609.

HEMOGENYX PHARMACEUTICALS PLC

NOTICE OF ANNUAL GENERAL MEETING

To be held at the offices of Shakespeare Martineau LLP, 60 Gracechurch Street, London EC3V 0HR

on 30 June at 2.00 p.m. BST

This document should be read as a whole. Your attention is drawn to the letter from the Chairman of the Company which is set out in this document and which recommends that you vote in favour of the ordinary resolutions and special resolutions (the "Resolutions") to be proposed at the Annual General Meeting ("AGM").

Notice of the AGM of the Company, to be held at the offices of Shakespeare Martineau LLP, 60 Gracechurch Street, London EC3V 0HR on 30 June 2022 at 2.00 p.m. BST, is set out at the end of this document.

Action to be taken by shareholders of the Company ("Shareholders") in respect of the AGM is set out on page 3 of this document. Shareholders are asked to complete and return the enclosed Form of Proxy in accordance with the instructions printed thereon as soon as possible, but in any event so as to be received by Computershare Investor Services PLC ("Computershare") at The Pavilions, Bridgwater Road, Bristol, BS99 6ZY or by scanning a signed copy and emailing this to #UKCSBRS.External- [e-mail] not later than 2.00 p.m. BST on 28 June 2022, being 48 hours before the AGM (or in the case of any adjournment, not later than 48 hours before the time fixed for the adjourned meeting (excluding any part of such 48 hour period falling on a non-working day)). Shareholders who hold Ordinary Shares in CREST may also appoint a proxy using CREST by following the instructions set out in the Form of Proxy and this document.

The completion and return of the Form of Proxy (by post or email, or transmission of a proxy appointment through CREST or by any other procedure described in this document) will not prevent you from attending and voting at the AGM, if you are entitled to and wish to do so. If you have any questions about this document or the AGM, or are in any doubt as to how to complete the Form of Proxy or to submit your proxy electronically, please call Computershare between 8:30 a.m. and 5:30 p.m. Monday to Friday (except UK public holidays) on [phone]. Calls from outside the UK will be charged at the applicable international rate. Different charges may apply to calls from mobile telephones. Please note that calls may be monitored or recorded and Computershare cannot give any financial,

legal or tax advice. A copy of this document will also be available on the Company's website, https://hemogenyx.com.

Letter from the Chairman of Hemogenyx Pharmaceuticals plc

(Registered and incorporated in England and Wales with Company number 08401609)

Registered Office

5 Fleet Place

London

EC4M 7RD

United Kingdom

8 June 2022

Dear Shareholder,

I am writing to give you details of the Company's 2022 AGM which will be held at 2.00 p.m. BST on 30 June 2022 at the offices of Shakespeare Martineau LLP, 60 Gracechurch Street, London EC3V 0HR. The formal notice of AGM is set out on page 4 of this document and an explanation of the business to be considered and voted on at the AGM is set out on page 5.

How to attend the AGM

If you are coming to the AGM, please bring the Attendance Card portion of the Form of Proxy with you. It authenticates your right to attend, speak and vote at the AGM and will speed your admission. You may also find it useful to bring the Notice of AGM and the 2021 Annual Report and Accounts so that you can refer to them at the AGM.

How to vote

Your vote is important to us. The Directors have taken the decision that voting on the Resolutions at the AGM will be taken on a show of hands. The proxy results will also be displayed at the AGM.

Our registrar, Computershare Investor Services PLC, must receive your online or postal proxy appointment and voting instructions by 2.00 p.m. BST on 28 June 2022 at the latest to ensure that your vote is counted. Details of how to submit a proxy are set out on page 6 of this document.

How to ask questions

Shareholders wishing to raise any questions relating to the business of the AGM may do so by submitting them to the Chair by email to company. [e-mail] in advance of the AGM. The Company will endeavour to publish and maintain an appropriate summary of responses on its website in advance of the AGM. All Shareholders or their proxies in attendance will have the opportunity to ask questions at the AGM. The Chair of the AGM will ensure that all such questions relating to the formal business of the AGM are addressed during the AGM, unless no response is required to be provided under the Companies Act or the provision of a response would, at the Chair's discretion, otherwise be undesirable in the interests of the Company or the good order of the AGM.

Business of the AGM

The business we will discuss at the AGM is made up of resolutions that are regularly brought to Shareholders. The formal notice of AGM and the Resolutions to be proposed at the AGM are set out on page 4 of this document. The following is a brief summary of the items of business:

• Resolution 1 relates to the receipt and adoption of the Company's annual accounts for the financial year ended 31 December 2021 together with the directors' reports and auditor's report (the "2021 Annual Report and Accounts") on those accounts;
• Resolution 2 relates to the approval of the Directors' Remuneration Report which is set out in the 2021 Annual Report and Accounts;
• Resolution 3 relates to the re-appointment of the auditors;
• Resolution 4 authorises the Audit Committee to agree the auditor's remuneration;
• Resolution 5 relates to the approval of the 2021 Equity Incentive Plan with Non-EmployeeSub-Plan;
• Resolution 6 relates to the Directors' authority to allot shares;
• Resolution 7 relates to the disapplication of pre-emption rights;
• Resolution 8 relates to the Directors' authority to call a general meeting (other than an annual general meeting) of the Company on a reduced notice period.

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Action to be taken

Please check that you have received the following:

• a Form of Proxy for use in respect of the AGM on 30 June 2022; and
• a pre-paid envelope for use in the UK only for the return of the Form of Proxy.

If you have not received all of these documents, please contact the Shareholder Helpline operated by Computershare between 8:30 a.m. and 5:30 p.m. Monday to Friday (except UK public holidays) on [phone]. Calls from outside the UK will be charged at the applicable international rate. Different charges may apply to calls from mobile telephones. Please note that calls may be monitored or recorded, and Computershare cannot provide advice on the merits of the Resolutions or give any financial, legal or tax advice.

Shareholders are required to cast or amend proxy voting instructions in respect of the AGM not later than 48 hours before the AGM (or in the case of any adjournment, not later than 48 hours before the time fixed for the adjourned meeting (excluding any part of such 48 hour period falling on a non-working day)). Shareholders are entitled to appoint a proxy in respect of some or all of their Ordinary Shares and may also appoint more than one proxy, provided that each proxy is appointed to exercise the rights attached to a different share or shares held by such holder. Shareholders who wish to appoint more than one proxy in respect of their holding of Ordinary Shares should contact Computershare for further Forms of Proxy or photocopy the Form of Proxy as required.

Sending the Form of Proxy by post or by email

Please complete and sign the Form of Proxy in accordance with the instructions printed thereon and return the Form of Proxy to Computershare, the Company's registrar, either (i) by post to Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol, BS99 6ZY, or (ii) by emailing a scanned copy to #[e-mail], so as to be received as soon as possible and in any event not later than at 2.00 p.m. BST on 28 June 2022, being 48 hours before the AGM (or in the case of any adjournment, not later than 48 hours before the time fixed for the adjourned meeting (excluding any part of such 48 hour period falling on a non-working day)).

The completion and return of the Form of Proxy by post or email (or transmission of a proxy appointment through CREST or by any other procedure described in this document) will not prevent you from attending and voting at the AGM, if you are entitled to and wish to do so.

If the Form of Proxy is not lodged by the relevant time, it will be invalid.

Appointment of proxies through CREST

CREST members who wish to appoint a proxy or proxies by utilising the CREST electronic proxy appointment service may do so for the meeting and any adjournment(s) of it by using the procedures described in the CREST Manual (available from https://www.euroclear.com/site/public/EUI). CREST Personal Members or other CREST sponsored members, and those CREST members who have appointed a voting service provider(s), should refer to their CREST sponsor or voting service provider(s), who will be able to take the appropriate action on their behalf. In order for a proxy appointment made by means of CREST to be valid, the appropriate CREST message (a CREST Proxy Instruction) must be properly authenticated in accordance with Euroclear UK & Ireland Limited's (EUI) specifications and must contain the information required for such instructions, as described in the CREST Manual. The message must be transmitted so as to be received by Computershare (ID: 3RA50) by no later than 2.00 p.m. BST on 28 June 2022. For this purpose, the time of receipt will be taken to be the time (as determined by the timestamp applied to the message by the CREST Applications Host) from which Computershare is able to retrieve the message by enquiry to CREST in the manner prescribed by CREST.

CREST members and, where applicable, their CREST sponsors or voting service providers should note that EUI does not make available special procedures in CREST for any particular messages. Normal system timings and limitations will therefore apply in relation to the input of CREST Proxy Instructions. It is the responsibility of the CREST member concerned to take (or, if the CREST member is a CREST personal member or sponsored member or has appointed a voting service provider(s), to procure that his CREST sponsor or voting service provider(s) take(s)) such action as shall be necessary to ensure that a message is transmitted by means of the CREST system by any particular time.

In this connection, CREST members and, where applicable, their CREST sponsors or voting service providers are referred, in particular, to those sections of the CREST Manual concerning practical limitations of the CREST system and timings. The Company may treat as invalid a CREST Proxy Instruction in the circumstances set out in Regulation 35(5)(a) of the Uncertificated Securities Regulations 2001.

Recommendation

The formal notice of AGM is set out on page 4 of this document and an explanation of each of the Resolutions to be considered at the AGM may be found on page 5 of this document.

The Directors believe that the passing of the Resolutions is in the best interests of the Company and the Shareholders taken as a whole. The Directors unanimously recommend that Shareholders vote, or procure their vote, in favour of the Resolutions as they intend to do in respect of their own beneficial holdings of Ordinary Shares, amounting in aggregate to 122,231,632 Ordinary Shares representing approximately 12.48 per cent. of the voting rights of the current issued Ordinary Share capital of the Company.

Thank you for your ongoing support of the Company.

Yours faithfully

Professor Sir Marc Feldmann

Chairman

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HEMOGENYX PHARMACEUTICALS PLC

(the "Company")

(Registered and incorporated in England and Wales with Company number 08401609)

NOTICE IS HEREBY GIVEN that the Annual General Meeting (the "AGM") of the Company will be held at the offices of Shakespeare Martineau LLP, 60 Gracechurch Street, London EC3V 0HR on 30 June 2022 at 2.00 p.m. to consider and if thought fit, pass the following resolutions. Resolutions 1 to 6 will be proposed as ordinary resolutions and resolutions 7 and 8 will be proposed as special resolutions.

Ordinary resolutions

Annual Report and Accounts

1. To receive and adopt the Company's annual accounts for the financial year ended 31 December 2021 together with the directors' reports and auditor's report on those accounts (the "2021 Annual Report and Accounts").

Directors' Remuneration Report

2. To approve the Directors' Remuneration Report (other than the Remuneration Policy) as set out in the 2021 Annual Report and Accounts, for the financial year ended 31 December 2021.

External auditor's reappointment and remuneration

1. To reappoint PKF Littlejohn LLP as the Company's auditor until the conclusion of the next annual general meeting of the Company.
2. To authorise the Audit Committee to determine the level of the auditor's remuneration.

Employee Incentive Plan and Non-EmployeeSub-Plan

5. (a) To approve the Hemogenyx Pharmaceuticals plc Equity Incentive Plan with Non-EmployeeSub-Plan in the form published on the Company's web site and available at the Company's registered office (the "Plan") adopted by the Board on 27 July 2021;

1. to authorise a maximum of 30,000,000 ordinary shares for issuance under the Plan;
2. to authorise the grant of a maximum of 30,000,000 ordinary shares as Incentive Options (as defined in the Plan); and
3. to authorise the directors to do all acts and things as are or may be necessary or expedient to carry the same into effect, notwithstanding that the direc- tors may be interested in the same.

Directors' authority to allot shares

6. To authorise the board of directors (the "Board" or the "Directors"), generally and unconditionally for the purpose of section 551 of the U.K. Companies Act 2006 (the "Companies Act") to exercise all the powers of the Company to allot shares in the Company or to grant rights to subscribe for or to convert any security into shares in the Company ("Rights") up to £3,265,830.74 in nominal value of ordinary shares of £0.01 each in the capital of the Company provided that this authority shall, unless renewed, varied or revoked by the Company, expire at the earlier of the date falling 15 months from the date of the passing of this Res- olution or the conclusion of the Company's next annual general meeting, save that the Company may, before such expiry, make an offer or agreement which would or might require shares to be allotted and the Directors may allot shares in pursuance of such offer or agreement notwithstanding that the authority conferred by this Resolution has expired.

All previous authorities conferred upon the Directors to allot shares in the Company or to grant Rights are revoked subject to any allotment, offer or agreement which would or might require equity securities or other securities to be allotted after the expiry of such period already made pursuant thereto and without prej- udice to any allotment of the shares or grant of Rights already made, offered or agreed to be made pursuant to such authorities.

Special resolutions

Disapplication of pre-emption rights

7. To authorise the Directors, subject to the passing of Resolution 6, and in accordance with the power conferred on the Directors by the Company's articles of association, to allot equity securities (as defined in the Companies Act) for cash under the authority given by that Resolution and/or to sell ordinary shares held by the Company as treasury shares for cash as if section 561 of the Companies Act did not apply to any such allotment or sale, provided that such authority shall be limited to:

1. the allotment of equity securities in connection with an offer or issue of equity securities to or in favour of (i) holders of ordinary shares in proportion (as nearly as may be practicable) to their existing holdings and (ii) holders of other equity securities if this is required by the rights of those securities or, if the Directors consider it necessary, as permitted by the rights of those securities; and
2. the allotment of equity securities or sale of treasury shares (otherwise than pursuant to Resolution 7(a) above) up to an aggregate nominal amount of £1,959,498.64

in each case, including any arrangements in connection with any issue of equity securities as they deem necessary or expedient (a) to deal with equity securities representing fractional entitlements, (b) to deal with legal or practical problems in the laws of any territory, or (c) the requirements of any regulatory body, on the basis that this authority shall apply until (unless previously renewed, varied or revoked by the Company at a general meeting) the earlier of the date falling 15 months from the date of the passing of this Resolution or the conclusion of the Company's next annual general meeting, save that the Company shall be entitled to make an offer or agreement which would or might require equity securities to be allotted or treasury shares to be sold pursuant to Resolutions 7(a) and 7(b) before the expiry of its power to do so, and the Directors shall be entitled to issue or sell from treasury the equity securities pursuant to any such offer or agreement after that expiry date.

Notice of meetings other than AGMs

8. That a general meeting other than an Annual General Meeting may be called on not less than 14 clear days' notice during the period from the date of the passing of this resolution 13 until the conclusion of the next Annual General Meeting of the Company.

BY ORDER OF THE BOARD	Registered Office:
Andrew Wright	5 Fleet Place
Company Secretary	London EC4M 7RD
8 June 2022

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EXPLANATORY NOTES TO THE RESOLUTIONS

References to page numbers in the 2021 Annual Report and Accounts for the financial year ended 31 December 2021 are to the signed version of the report published on the Company's website and uploaded to the National Storage Mechanism on 29 April 2022. These page numbers may differ from the printed version of the Annual Report accompanying this notice.

RESOLUTION 1 - ANNUAL REPORT AND ACCOUNTS

The Directors are required to present to the AGM the 2021 Annual Report and Accounts for the financial year ended 31 December 2021.

RESOLUTION 2 - DIRECTORS' REMUNERATION REPORT

In accordance with section 439 of the Companies Act, Shareholders are requested to approve the Directors' Remuneration Report. The Directors' Remuneration Report is set out on pages 31 to 36 of the 2021 Annual Report and Accounts. The vote is advisory only and does not affect the actual remuneration paid to an individual director.

RESOLUTIONS 3 AND 4 - EXTERNAL AUDITOR'S REAPPOINTMENT AND REMUNERATION

The auditor is appointed at every general meeting at which accounts are presented to Shareholders. The current appointment of PKF Littlejohn LLP as the Compa- ny's auditor will end at the conclusion of the AGM and it has advised of its willingness to stand for reappointment. In accordance with the provisions of the Code of Corporate Governance published by the Financial Reporting Council in 2018, it is recommended best practice for the Audit Committee to be authorised to agree how much the auditor should be paid and Resolution 4 grants this authority to the Audit Committee.

RESOLUTION 5 - APPROVAL OF EMPLOYEE INCENTIVE PLAN AND NON-EMPLOYEESUB-PLAN

The Directors adopted the Hemogenyx Pharmaceuticals plc 2021 Equity Incentive Plan with Non-EmployeeSub-Plan (the "EIP") for the grant of options, restricted shares, and restricted share units to employees, directors and consultants of the Company and its subsidiaries over ordinary shares in the capital of the Company on 27 July 2021. The decision should be approved by Shareholders within 12 months following the date of adoption. The EIP enables the grant of options (including potentially tax efficient Incentive Stock Options) to employees in the U.S., restricted shares, restricted share units and performance share awards to employees, Directors and consultants of the Company and its subsidiaries. The number of shares available for grants under the EIP is 30 million, subject to adjustment in the event of a variation of share capital, and can be increased with shareholder approval. The Directors have determined that the adoption of the EIP was advisable and in the best interests of the Company and its Shareholders and most likely to promote the success of the Company for the benefit of its members as a whole.

RESOLUTION 6 - ALLOTMENT OF SHARE CAPITAL

Resolution 6 grants the Directors general authority to allot ordinary shares in the capital of the Company or to grant rights to subscribe for, or to convert any security into, such shares in the Company up to an aggregate nominal amount of £3,265,830.74, representing approximately one-third of the Company's current issued share capital.

Resolutions 1 to 6 will be proposed as ordinary resolutions and require that more than half of the votes cast must be in favour of a resolution for it to be passed.

RESOLUTION 7 - DISAPPLICATION OF PRE-EMPTION RIGHTS

Section 561(1) of the Companies Act requires that on an allotment of new shares for cash, such shares must first be offered to existing Shareholders in proportion to the number of shares that they each hold at that time. The Directors believe that there may be circumstances when it is in the best interests of the Company to allot new ordinary shares either on an entirely non-pre-emptive basis or in a way that departs from the statutory requirements set out in the Companies Act. Resolution 6 grants the Directors general authority to allot shares or grant rights over shares for cash and otherwise than to existing shareholders pro rata to their holdings. The authority will be limited to shares of a maximum aggregate nominal value of £1,959,498.64, being 20% of the issued ordinary share capital. This authority, if given, will expire (unless previously revoked or varied by the Company in general meeting) at the earlier of the conclusion of the next annual general meeting in 2023 or on the date which is 15 months after the relevant resolution is passed.

RESOLUTION 8 - NOTICE OF MEETINGS OTHER THAN ANNUAL GENERAL MEETINGS

The Directors wish to obtain the flexibility and benefit from the ability to call general meetings on 14 clear days' notice and this Resolution, which is proposed as a special resolution, seeks authority from Shareholders for this flexibility. Such approval will not affect annual general meetings, which will continue to be held on at least 21 clear days' notice. In the event that this authority is to be exercised, the Directors will ensure that it is not used as a matter of routine, but only where the flexibility is merited by the business of the meeting and is thought to be to the advantage of Shareholders as a whole. The Company intends to meet the requirements for a means of electronic voting to be made available to all Shareholders before calling a meeting on 14 clear days' notice. The approval will be effective until the Compa- ny's next annual general meeting, when it is intended that a similar resolution will be proposed.

Resolutions 7 and 8 will be proposed as special resolutions and require that at least three quarters of the votes cast must be in favour of a resolution for it to be passed.

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