Itaconix : View Circular and Notice of General Meeting – June 2023

THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION. If you are in any doubt about the contents of this document or as to what 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 (as amended) if you are a resident of the United Kingdom or, if not, another appropriately authorised independent professional adviser.

If you have sold or otherwise transferred all of your ordinary shares in the Company, please send this document and the accompanying proxy form as soon as possible to the purchaser or transferee, or to the 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 (but not all) of your ordinary shares in the Company, please retain these documents ad consult the stockbroker or other agent through whom the sale or transfer was effected.

ITACONIX plc

(Registered in England and Wales with company number 08024489)

Notice of Annual General Meeting

Proposed Potential Share Capital Consolidation

to be held at the offices of Fieldfisher LLP, 9th Floor, Riverbank House, 2 Swan Lane,

London EC4R 3TT, United Kingdom on 28 June 2023 at 11:00 a.m.

This document should be read as a whole. Your attention is drawn to the letter from the Chair of the Company set out on page 2 of this document, which contains the recommendation by the Directors of the Company to shareholders to vote in favour of the resolutions to be proposed at the Annual General Meeting ("AGM").

Notice of the AGM (the "AGM Notice") is set out on pages 3 to 5 of this document.

If you are unable to attend the AGM, please complete and submit a form of proxy in accordance with the instructions set out in the explanatory notes to this document set out on page 6 of this document. Appointment of a proxy will not preclude shareholders from attending and voting at the AGM should they choose to do so.

If you hold your ordinary shares in uncertificated form (i.e. in CREST), you may appoint a proxy for the AGM 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 Link Group (under CREST Participation ID RA10 by no later than 11:00 a.m. on 26 June 2023. The time of receipt will be taken to be the time from which Link Group are able to retrieve the message by enquiry to CREST in the manner prescribed by CREST.

As an alternative to completing the hard-copy form of proxy, you will be able to vote electronically by visiting the shareholder portal at www.signalshares.com. You will need to log into your Signal Shares account or register if you have not previously done so. To register you will need your Investor Code ("IVC") which is detailed on your share certificate or available from Link Group.

Itaconix plc

(the "Company")

(Registered in England and Wales with company number 08024489)

Fieldfisher, Riverbank House, 2 Swan Lane, London EC4R 3TT, United Kingdom

Directors:

Peter Nieuwenhuizen (Non-Executive Chair)

John Snow (Chief Executive Officer)

Laura Denner (Chief Financial Officer)

Paul LeBlanc (Non-Executive Director)

5 June 2023

Dear Shareholder

Notice of Annual General Meeting

I have pleasure in sending you notice convening the annual general meeting of Itaconix plc (the "Company"). The meeting will be held on Wednesday, 28 June 2023 at 11:00 a.m. at Fieldfisher's offices, 9th Floor, Riverbank House, 2 Swan Lane, London EC4R 3TT, United Kingdom. As you will see from the formal notice of meeting which follows this letter, there are a number of items of business to be considered and the purpose of each resolution to be proposed is set out in the Explanatory Notes to the Resolutions starting on page 8.

You can vote in respect of your shareholding by attending the meeting or by appointing one or more proxies to attend the meeting and vote on your behalf.

Proxies may be appointed by either:

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completing and returning the enclosed proxy form; or

using the CREST electronic proxy appointment service (for CREST members only);

or by logging into the shareholder portal at www.signalshares.com.

In all cases, the notice of appointment of a proxy should reach the Company's registrar, Link Group, by no later than 11:00 a.m. on 26 June 2023. Please refer to the Notes to the Notice of Meeting starting on page 6 and the enclosed proxy form for detailed instructions.

Recommendation

Your directors consider that the resolutions to be proposed will promote the success of the Company for the benefit of its shareholders as a whole. Accordingly, your directors unanimously recommend that shareholders vote in favour of all of the resolutions, as they intend to do in respect of their own beneficial holdings.

Yours faithfully

Peter Nieuwenhuizen

Chair

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ITACONIX PLC

(Registered in England and Wales with company number 08024489)

NOTICE OF ANNUAL GENERAL MEETING

NOTICE IS HEREBY GIVEN that the Annual General Meeting of Itaconix plc (the "Company") will be held on Wednesday, 28 June 2023 at 11:00 a.m. at Fieldfisher's offices, 9th Floor, Riverbank House, 2 Swan Lane, London EC4R 3TT, United Kingdom. The business of the meeting will be to consider and, if thought fit, to pass the following resolutions, of which resolutions 1 to 8 will be proposed as ordinary resolutions of the Company and resolutions 9 and 10 will be proposed as special resolutions of the Company:

ORDINARY RESOLUTIONS

1. To receive the audited financial statements of the Company, the strategic report, the directors' report and the auditor's report for the financial year ended 31 December 2022.
2. To re-appoint Peter Nieuwenhuizen as a director of the Company.
3. To re-appoint Laura Denner as a director of the Company.
4. To re-appoint Paul LeBlanc as a director of the Company.
5. To re-appoint BDO LLP as auditors of the Company, to hold office from the conclusion of this meeting until the conclusion of the next general meeting at which audited financial statements of the Company are laid before the Company.
6. To authorise the directors to determine the remuneration of the Company's auditors.
7. THAT every existing 50 ordinary shares of £0.01 each in the capital of the Company in issue
   and shown in the register of members of the Company at 6.00 p.m. (London time) on such date as the Directors may determine (the "Existing Ordinary Shares") be consolidated into one ordinary share of £0.5 in the capital of the Company, such ordinary shares having the same rights, and being subject to the same restrictions, as the Existing Ordinary Shares, as set out in the articles of association of the Company, provided that at the date of consolidation the closing mid-market price of the Existing Ordinary Shares is not less than £0.04 and that this power shall expire on 28 June 2024.
8. THAT the directors of the Company (the "Directors") are generally and unconditionally authorised for the purposes of section 551 of the Companies Act 2006 (the "Act"), in substitution for all previous authorisations, to exercise all the powers of the Company to allot shares in the Company and to grant rights to subscribe for or convert any security into shares in the Company ("Rights"):
9. 1. up to an aggregate nominal amount of £2,247,686.85; and
   2. in relation to equity securities (within the meaning of section 560 of the Act), up to an aggregate nominal amount of £4,495,373.70 (after deducting from such amount the aggregate nominal amount of any shares allotted and Rights granted under paragraph (a) above) in connection with an offer by way of rights issue made:
   3. 1. to holders of ordinary shares in the Company in proportion (as nearly as may be practicable) to the respective numbers of ordinary shares held by them on the record date for such offer; and
      2. to holders of other equity securities as may be required by the rights attached to those securities or, if the Directors consider it desirable, as may be permitted by such rights,

but subject in each case to such exclusions or other arrangements as the Directors may deem necessary or expedient in relation to treasury shares, fractional entitlements, record dates or legal or practical problems in or under the laws of any territory or the requirements of any regulatory body or stock exchange,

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and this authorisation shall, unless previously revoked by resolution of the Company, expire on at midnight on the date falling 15 months after the passing of this resolution or, if earlier, at the conclusion of the annual general meeting of the Company to be held in 2024. The Company may, at any time before such expiry, make offers or enter into agreements which would or might require shares to be allotted or Rights to be granted after such expiry and the Directors may allot shares or grant Rights in pursuance of any such offer or agreement as if this authorisation had not expired.

SPECIAL RESOLUTIONS

9. THAT, subject to the passing of Resolution 8 above, the Directors be authorised to allot equity securities (as defined in the 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 Act did not apply to any such allotment or sale, such authority to be limited to:

1. the allotment of equity securities or sale of treasury shares made in connection with an offer by way of rights issue:
2. 1. to holders of ordinary shares in the Company in proportion (as nearly as may be practicable) to the respective numbers of ordinary shares held by them on the record date for such offer; and
   2. to holders of other equity securities as may be required by the rights attached to those securities or, if the Directors consider it desirable, as may be permitted by such rights,

but subject in each case to such exclusions or other arrangements as the Directors may deem necessary or expedient in relation to treasury shares, fractional entitlements, record dates, legal or practical problems in or under the laws of any territory or the requirements of any regulatory body or stock exchange;

1. the allotment of equity securities or sale of treasury shares (otherwise than under paragraph (a) above) up to a nominal amount of £674,306.05; and
2. the allotment of equity securities or sale of treasury shares (otherwise than under paragraph (a) or paragraph (b) above) up to a nominal amount equal to 20% of any allotment of equity securities or sale of treasury shares from time to time under paragraph (b) above, such authority to be used only for the purposes of making a follow- on offer which the Directors determine to be of a kind contemplated by paragraph 3 of Section 2B of the Statement of Principles on Disapplying Pre-Emption Rights most recently published by the Pre-Emption Group prior to the date of this notice,

such authority to expire at the end of the next annual general meeting of the Company (or, if earlier, at midnight on the date falling 15 months after the date of the passing of this resolution) but, in each case, prior to its expiry the Company may make offers, and enter into agreements, which would, or might, require equity securities to be allotted (and treasury shares to be sold) after the authority expires and the Directors may allot equity securities (and sell treasury shares) under any such offer or agreement as if the authority had not expired.

10. THAT, subject to the passing of Resolution 8 above, the Directors be authorised to allot equity securities (as defined in the 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 Act did not apply to any such allotment or sale, such authority to be limited to:

1. the allotment of equity securities or sale of treasury shares up to a nominal amount of £674,306.05, such authority to be used only for the purposes of financing (or refinancing,
   if the authority is to be used within 12 months after the original transaction) a transaction which the Directors determine to be either an acquisition or a specified capital investment of a kind contemplated by the Statement of Principles on Disapplying Pre-Emption Rights most recently published by the Pre-Emption Group prior to the date of this notice; and
2. the allotment of equity securities or sale of treasury shares (otherwise than under paragraph 10 above) up to a nominal amount equal to 20% of any allotment of equity securities or sale of treasury shares from time to time under paragraph 10 above, such authority to be used only for the purposes of making a follow-on offer which the Directors

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determine to be of a kind contemplated by paragraph 3 of Section 2B of the Statement of Principles on Disapplying Pre-Emption Rights most recently published by the PreEmption Group prior to the date of this notice,

such authority to expire at the end of the next annual general meeting of the Company (or, if earlier, at midnight on the date falling 15 months after the date of the passing of this resolution) but, in each case, prior to its expiry the Company may make offers, and enter into agreements, which would, or might, require equity securities to be allotted (and treasury shares to be sold) after the authority expires and the Directors may allot equity securities (and sell treasury shares) under any such offer or agreement as if the authority had not expired.

BY ORDER OF THE BOARD

Laura Denner

Chief Financial Officer and Company Secretary

Registered office:

Fieldfisher LLP

Riverbank House

2 Swan Lane

London

EC4R 3TT

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