SPECIAL MEETING OF SHAREHOLDERS

NOTICE OF ANNUAL AND

SPECIAL MEETING OF SHAREHOLDERS

To the shareholders of Acasti Pharma Inc. (the "Corporation"):

NOTICE IS HEREBY GIVEN THAT that the annual and special meeting of the shareholders

(the "Meeting") of the Corporation will be held at the Giuseppe Saputo meeting room on the ground floor of the

Sheraton Laval located at 2440 Aut. Des Laurentides, Laval, Qu bec, H7T 1X5, on August 27, 2019 at 10:00 a.m., for

the following purposes:

SIGNED IN LAVAL, QUEBEC, AS AT, July 24, 2019.

By Order of the Board of

Shareholders may exercise their rights by attending the Meeting

or by completing a form of proxy. The Directors of the Corporation have established July 23, 2019 as the record date for the purpose

of determining the Corporation's shareholders which are entitled to receive notice of and to vote at the Meeting. Should

you be unable to attend the Meeting in person, please complete, date and sign the enclosed form of proxy and return it in the envelope

provided for that purpose. Proxies must be received by the transfer agent and registrar of the Corporation, Computershare Investor

Services Inc. (Attention: Proxy Department), 100 University Avenue, 9th Floor, Toronto, Ontario, Canada, M5J 2Y1,

no less than 48 hours (excluding Saturdays, Sundays and holidays) prior to the day of the Meeting. Your shares will be voted in

accordance with your instructions as indicated on the form of proxy, or failing instructions, in the manner set forth in the Circular.

MANAGEMENT INFORMATION

Unless otherwise indicated, the following information is given as

at July 24, 2019 and all amounts in dollars refer to Canadian currency.

SOLICITATION OF PROXIES

This management information circular (this "Circular")

is provided in connection with the solicitation by the management of Acasti Pharma Inc. (the "Corporation" or

"Acasti") of proxies to be used at the annual and special meeting (the "Meeting") of the

shareholders of the Corporation (the "Shareholders") to be held at the Giuseppe Saputo meeting room on the ground

floor of the Sheraton Laval located at 2440 Aut. Des Laurentides, Laval, Qu bec, H7T 1X5, on August 27, 2019 at 10:00 a.m.,

and any adjournment thereof for the purposes set out in the accompanying notice of Meeting (the "Notice of Meeting").

It is expected that the solicitation will be made primarily by mail. However, directors, officers and employees of the Corporation

may also solicit proxies by telephone, fax, email or in person. The cost of solicitation of proxies will be borne by the Corporation.

APPOINTMENT AND REVOCATION

The persons named in the enclosed form of proxy are directors of

the Corporation ("Directors") or officers of the Corporation. Each Shareholder who is entitled to vote at the

Meeting is entitled to appoint a person, who need not be a Shareholder of the Corporation, to represent him or her at the Meeting

other than those whose names are printed on the accompanying form of proxy by inserting such other person's name in the blank

space provided in the form of proxy and signing the form of proxy or by completing and signing another proper form of proxy. To

be valid, the duly completed form of proxy must be deposited at the offices of Computershare Investor Services Inc. (Attention:

Proxy Department), 100 University Avenue, 9th Floor, Toronto, Ontario M5J 2Y1 no less than 48 hours (excluding Saturdays,

Sundays and holidays) prior to the day of the Meeting or, by a registered Shareholder, with the Secretary or the Chairman of the

Meeting at the time and place of the Meeting or any adjournment thereof. The instrument appointing a proxy-holder must be executed

by the Shareholder or by his attorney authorized in writing or, if the Shareholder is a corporate body, by its authorized officer

A Shareholder who has given a proxy may revoke it, as to any motion

on which a vote has not already been cast pursuant to the authority conferred by it, by an instrument in writing executed by the

Shareholder or by the Shareholder's attorney authorized in writing or, if the Shareholder is a corporation, under its corporate

seal or by an officer or attorney thereof duly authorized. The revocation of a proxy, in order to be acted upon, must be deposited

with Computershare Investor Services Inc. (Attention: Proxy Department), 100 University Avenue, 9th Floor, Toronto,

Ontario M5J 2Y1 at any time but no less than 48 hours (excluding Saturdays, Sundays and holidays) prior to the day of the Meeting,

or any adjournment thereof at which the proxy is to be used, or, by a registered Shareholder, with the Secretary or the Chairman

of the Meeting on the day of the Meeting or any adjournment thereof, or in any other manner permitted by law.

In addition, a proxy may be revoked by the Shareholder executing

another form of proxy bearing a later date and depositing same at the offices of Computershare Investor Services Inc. (Attention:

Proxy Department), 100 University Avenue, 9th Floor, Toronto, Ontario M5J 2Y1 no less than 48 hours (excluding Saturdays,

Sundays and holidays) prior to the day of the Meeting or, by a registered Shareholder, with the Secretary or the Chairman of the

Meeting at the time and place of the Meeting or any adjournment thereof or by the Shareholder personally attending the Meeting

and voting his or her shares.

EXERCISE OF DISCRETION

All Class A shares of the Corporation (the "Common Shares")

represented at the meeting by properly executed proxies will be voted and where a choice with respect to any matter to be acted

upon has been specified in the instrument of proxy, the Common Shares represented by the proxy will be voted in accordance with

such specifications. In the absence of any such specifications, the management designees, if named as proxy, will vote in

favour of all the matters set out herein. Instructions with respect to voting will be respected by the persons designated

in the enclosed form of proxy. With respect to amendments or variations to matters identified in the Notice of Meeting and with

respect to other matters that may properly come before the Meeting, such Common Shares will be voted by the persons so designated

at their discretion. At the time of printing this Circular, management of the Corporation knows of no such amendments, variations

NON-REGISTERED SHAREHOLDERS

Only registered Shareholders or the persons they appoint as their

proxies are permitted to vote at the Meeting. However, in many cases, Common Shares beneficially owned by a person (a "Non-Registered

Shareholder") are registered either:

Intermediaries are required to forward the Meeting Materials to

Non-Registered Shareholders, and often use a service Corporation for this purpose. Non-Registered Shareholders will either:

In either case, the purpose of these procedures is to permit Non-Registered

Shareholders to direct the voting of the Common Shares which they beneficially own.

Should a Non-Registered Shareholder who receives a voting instruction

form wish to vote at the Meeting in person (or have another person attend and vote on behalf of the Non-Registered Shareholder),

such Non-Registered Shareholder should print his or her own name, or that of such other person, on the voting instruction form

and return it to the Intermediary or its service Corporation. Should a Non-Registered Shareholder who receives a proxy form wish

to vote at the Meeting in person (or have another person attend and vote on behalf of the Non-Registered Shareholder), the Non-Registered

Shareholder should strike out the names of the persons set out in the proxy form and insert the name of the Non-Registered Shareholder

or such other person in the blank space provided and submit it to Computershare Investor Services Inc. at the address set out at

In all cases, Non-Registered Shareholders should carefully follow

the instructions of their Intermediary, including those regarding when, where and by what means the voting instruction form or

proxy form must be delivered.

A Non-Registered Shareholder may revoke voting instructions which

have been given to an Intermediary at any time by written notice to the Intermediary.

Shareholders registered as at July 23, 2019 (the "Record

Date") are entitled to attend and vote at the Meeting. Shareholders who wish to be represented by proxy at the Meeting

must, to entitle the person appointed by the proxy to attend and vote, deliver their proxies at the place and within the time set

forth in this Circular.

The Corporation's authorized capital consists of an unlimited

number of no par value Common Shares and an unlimited number of no par value Class B, Class C, Class D and Class E

preferred shares (collectively the "Preferred Shares"), issuable in one or more series.

The Corporation's Common Shares were consolidated on October

15, 2015 (the "Consolidation"), on the basis of one (1) post-Consolidation Common Share for every

ten (10) pre-Consolidation Common Shares, and each fractional Common Share resulting from the consolidation was rounded up (the

As at the Record Date, there were a total of 79,202,705 Common Shares

issued and outstanding and no Preferred Shares issued and outstanding. Each Common Share entitles its holder to one (1) vote.

The by-laws of the Corporation provide that during any meeting of

the Shareholders, the attendance, in person or by proxy, of the Shareholders representing ten percent (10%) of the Common Shares

shall constitute a quorum, provided that quorum shall not be less than two persons.

PRINCIPAL SHAREHOLDERS

Other than as set forth below, as at the Record Date, to the best