BELLUS Health : Amended and Restated Management Information Circular dated May 31, 2023

BELLUS HEALTH INC.

NOTICE AND

AMENDED AND RESTATED

MANAGEMENT INFORMATION CIRCULAR

FOR THE

ANNUAL AND SPECIAL MEETING

OF COMMON SHAREHOLDERS

TO BE HELD ON JUNE 30, 2023

May 31, 2023

BELLUS HEALTH INC.

NOTICE OF ANNUAL AND SPECIAL MEETING OF SHAREHOLDERS

NOTICE is hereby given that the annual and special meeting (the "Meeting") of the common shareholders of BELLUS Health Inc. (the "Company") will be held in person at 275 Armand Frappier Blvd., Laval, Québec, H7V 4A7 on June 30, 2023 at 11:30 a.m., Montréal time, for the following purposes:

1. to receive and consider the annual report of the directors to the shareholders and the financial statements of the Company for the financial year ended December 31, 2022, and the report of the auditors thereon;
2. to elect each of the directors for the ensuing year;
3. to appoint KPMG LLP, Chartered Accountants, as auditors of the Company and to authorize the Audit Committee to fix the auditors' remuneration;
4. to ratify and confirm the resolution approving the unallocated options under the Amended and Restated Stock Option Plan of the Company, the whole as more fully set forth in Schedule "A"hereto; and
5. to transact such further and other business as may properly be brought before the Meeting or any adjournment thereof.

Shareholders who are unable to participate in the Meeting are requested to date and sign the enclosed proxy and to mail it to or deposit it with the Company, c/o Computershare Investor Services Inc., 100 University Avenue, 8th Floor, Toronto, Ontario M5J 2Y1. In order to be valid and acted upon at the Meeting, proxies must be returned to the aforesaid address not less than 48 hours, excluding Saturdays, Sundays and holidays, before the date of the Meeting or any adjournment or postponement thereof at which the proxy is to be used.

If you are a registered shareholder or you have already given the Company instructions to send you printed documents, your amended and restated management proxy circular is attached to this Notice of Meeting.

The amended and restated management information circular is being mailed to all shareholders. Only registered shareholders or the persons they appoint as their proxyholders are permitted to vote at the Meeting. Non-registered shareholders should follow the instructions on the forms they receive so that their shares can be voted. No other securityholders of the Company are entitled to vote at the Meeting.

DATED at Montréal, Québec, Canada, May 31, 2023.

BY ORDER OF THE BOARD OF DIRECTORS

(signed) Sébastien Roy

Corporate Secretary

SHAREHOLDERS MAY EXERCISE THEIR VOTING RIGHTS BY ATTENDING THE MEETING OR BY COMPLETING A FORM OF PROXY. SHAREHOLDERS WHO ARE UNABLE TO BE PRESENT IN PERSON AT THE MEETING ARE REQUESTED TO COMPLETE, DATE AND SIGN THE ENCLOSED FORM OF PROXY AND MAIL IT TO THE COMPANY, C/O COMPUTERSHARE INVESTOR SERVICES INC., IN THE ENVELOPE PROVIDED FOR THAT PURPOSE. PLEASE REFER TO THE ACCOMPANYING AMENDED AND RESTATED MANAGEMENT INFORMATION CIRCULAR FOR ADDITIONAL PARTICULARS.

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AMENDED AND RESTATED MANAGEMENT INFORMATION CIRCULAR

PART 1.

VOTING INFORMATION

This amended and restated management information circular (the "Circular") replaces and supersedes the management information circular originally filed on SEDAR by BELLUS Health Inc. (the "Company") on March 30, 2023, and is furnished in connection with the solicitation by the management of the Company of proxies to be voted at the annual and special meeting of common shareholders (the "Meeting"), to be held in person at 275 Armand Frappier Blvd., Laval, Québec, H7V 4A7, on June 30, 2023 at 11:30 a.m., Montréal time, for the purposes set forth in the accompanying notice of the Meeting, and at any adjournment thereof. Except as otherwise stated, the information contained in this Circular is given as at May 31, 2023. All dollar amounts and references to $ or US$ are to United States dollars and references to CDN$ are to Canadian dollars.

SOLICITATION OF PROXIES

The enclosed proxy is being solicited by the management of the Company and the expenses of solicitation of proxies will be borne by the Company. The solicitation will be made primarily by mail; however, officers and regular employees of the Company may also solicit proxies by telephone, telecopier, electronic mail or in person.

APPOINTMENT AND REVOCATION OF PROXIES

The persons named in the enclosed form of proxy are directors or officers of the Company. Each shareholder is entitled to appoint any other person to represent him or her at the Meeting, and at any adjournment thereof.

A shareholder desiring to appoint another person (who need not be a shareholder) to represent him or her at the Meeting, and at any adjournment thereof, may do so either by striking out the names of the management nominees set forth in the form of proxy and by inserting such person's name therein or by completing another proper form of proxy and, in either case, sending the completed proxy in the enclosed reply envelope for delivery before the Meeting, or any adjournment thereof, or by depositing such proxy with the Chairman on the day of the Meeting, at the Meeting or any adjournment thereof.

A shareholder giving a proxy pursuant to this solicitation may revoke any such proxy by depositing an instrument in writing executed by the shareholder or by his or her attorney duly authorized in writing, or, if the shareholder is a corporation, under its corporate seal or by an officer or attorney of the corporation duly authorized in writing, with the Company, c/o Computershare Investor Services Inc. (the "Transfer Agent"), Attention: Proxy Department, 100 University Avenue, 8th Floor, North Tower, Toronto, Ontario M5J 2Y1, at any time up to and including the close of business two business days preceding the day of the Meeting, or any adjournment thereof, or with the Chairman on the day of the Meeting, at the Meeting or any adjournment thereof, before any vote is cast under the proxy's authority.

REGISTERED COMMON SHAREHOLDERS

Holders of common shares of the Company (the "Common Shares") listed as shareholders at the close of business on May 25, 2023 (the "Record Date"), will be entitled to vote at the Meeting, or any adjournment thereof, either in person or by proxy, in respect of all matters which may properly come before the Meeting, or any adjournment thereof.

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NON-REGISTERED COMMON SHAREHOLDERS

The names of the shareholders whose shares are held in the name of a broker or another intermediary will not appear on the list of shareholders of the Company. If you are not a registered shareholder of the Company, in order to vote you must a) obtain the material relating to the Meeting from your broker or other intermediary; b) complete the request for voting instructions sent to you by the broker or other intermediary; and c) follow the directions of the broker or other intermediary with respect to voting procedures.

In accordance with National Instrument 54-101 adopted by the Canadian Securities Administrators entitled "Communication with Beneficial Owners of Securities of a Reporting Issuer", the Company or the Transfer Agent is distributing copies of the material related to the Meeting directly to non-objecting beneficial shareholders. If you are a non-objecting beneficial shareholder, your name, address and information about your holdings of shares have been obtained in accordance with applicable securities regulatory requirements from the intermediary holding shares on your behalf. By choosing to send these materials to you directly, the Company (and not the intermediary holding on your behalf) has assumed responsibility for (i) delivering these materials to you, and (ii) executing your proper voting instructions. Please return your voting instructions as specified in the request for voting instructions.

In the case of objecting beneficial shareholders, applicable regulations in Canada require intermediaries to seek voting instructions from such shareholders in advance of the Meeting. Every intermediary has its own mailing procedures and provides its own return instructions, which should be carefully followed by objecting beneficial shareholders in order to ensure that their shares are voted at the Meeting. If you are an objecting beneficial shareholder, a broker or other intermediary will only vote the shares held by you if you provide instructions to your broker or other intermediary directly on how to vote. Without instructions, those shares may not be voted.

A non-objecting beneficial shareholder who has given voting instructions in accordance with the voting instruction form may revoke such voting instructions by following the instructions. If you are an objecting beneficial shareholder of the Company, the intermediary from whom you received the voting instruction form may be unable to take any action on the revocation if such revocation is not provided sufficiently in advance of the Meeting or any adjournment or postponement thereof.

If you are an objecting beneficial holder, you should submit your voting instructions to your intermediary or broker leaving sufficient time to ensure that your votes are received, from your intermediary or broker, by the Transfer Agent on behalf of the Company, as set forth under the heading "Appointment and Revocation of Proxies" in this Circular.

VOTING OF PROXIES

The persons named in the enclosed form of proxy will vote for or against or withhold from voting the shares in respect of which they are appointed in accordance with the directions of the shareholders appointing them.

In the absence of shareholder directions, Common Shares will be voted:

1. FOR the election as directors of each of those persons hereinafter named as management's nominees;
2. FOR the appointment of KPMG LLP, Chartered Accountants, as auditors of the Company and the authorization of the Audit Committee to fix the auditors' remuneration; and
3. FOR the ratification and confirmation of the resolution approving the unallocated options under the Plan, the whole as set forth in Schedule Ahereto.

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