Exhibit 99.1

EXECUTION VERSION

ACASTI PHARMA INC.

as the Corporation

and

COMPUTERSHARE TRUST COMPANY OF CANADA

as the Warrant Agent

WARRANT INDENTURE

Providing for the Issue of Warrants

Dated as of December 3, 2013

TABLE OF CONTENTS

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WARRANT INDENTURE

THIS WARRANT INDENTURE is dated as of December 3, 2013.

BETWEEN:

ACASTI PHARMA INC., a corporation incorporated under the laws of the Province of Québec (the “ Corporation ”),

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COMPUTERSHARE TRUST COMPANY OF CANADA , a trust company existing under the laws of Canada and authorized to carry on business in all provinces of Canada (the “ Warrant Agent ”),

WHEREAS pursuant to the terms and conditions of an underwriting agreement dated November 27, 2013 (the “ Underwriting Agreement ”) the between the Corporation, Euro Pacific Canada Inc. and National Securities Corporation (collectively, the “ Underwriters ”), the Corporation proposes to issue and sell 16,000,000 units (“ Units ”) of the Corporation (the “ Offering ”), each Unit comprised of one (1) Common Share (as defined herein) and one (1) Warrant (as defined herein);

AND WHEREAS for the purpose of the Offering, the Corporation is proposing to issue 16,000,000 Warrants and up to an additional 2,400,000 Warrants (assuming the exercise of the over-allotment option (the “ Over-Allotment Option ”) granted to the Underwriters) pursuant to this Indenture;

AND WHEREAS each Warrant shall, subject to adjustment, entitle the holder thereof to acquire one (1) Common Share upon payment of the Exercise Price (as defined below) upon the terms and conditions herein set forth;

AND WHEREAS as of the date hereof the Corporation has an effective Registration Statement (as defined below) under the U.S. Securities Act (as defined below);

AND WHEREAS all acts and deeds necessary have been done and performed to make the Warrants, when created and issued as provided in this Indenture, legal, valid and binding upon the Corporation with the benefits and subject to the terms of this Indenture;

AND WHEREAS the foregoing recitals are made as representations and statements of fact by the Corporation and not by the Warrant Agent;

NOW THEREFORE , in consideration of the premises and mutual covenants hereinafter contained and other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the Corporation hereby appoints the Warrant Agent as warrant agent to hold the rights, interests and benefits contained herein for and on behalf of those persons who from time to time become the holders of Warrants issued pursuant to this Indenture and the parties hereto agree as follows:

ARTICLE 1

INTERPRETATION

In this Indenture, including the recitals and schedules hereto, and in all indentures supplemental hereto:

“ Adjustment Period ” means the period from the Effective Date up to and including the Expiry Time;

“ Applicable Legislation ” means any statute of Canada or a province thereof, and the regulations under any such named or other statute, relating to warrant indentures or to the rights, duties and obligations of warrant agents under warrant indentures, to the extent that such provisions are at the time in force and applicable to this Indenture;

“ Applicable Securities Laws ” means the applicable securities laws, regulations, rules, rulings and orders, including the applicable federal and state securities laws and regulations of the United States, including the U.S. Securities Act, together with all related rules, policies, notices, blanket rulings, orders and all other regulatory instruments of the securities regulators in the Provinces of Quebec, Ontario, Manitoba, Alberta and British Columbia, and the policies of the TSXV;

“ Auditors ” means a firm of chartered accountants duly appointed as auditors of the Corporation;

“ Authenticated ” means (a) with respect to the issuance of a Warrant Certificate, one which has been duly signed by the Corporation and authenticated by manual signature of an authorized officer of the Warrant Agent, (b) with respect to the issuance of an Uncertificated Warrant, one in respect of which the Warrant Agent has completed all Internal Procedures such that the particulars of such Uncertificated Warrant as required by Section 2.7 are entered in the register of holders of Warrants, “ Authenticate ”, “ Authenticating ” and “ Authentication ” have the appropriate correlative meanings;

“ Book Entry Only Participants ” means institutions that participate directly or indirectly in the Depository’s book entry registration system for the Warrants;

“ Book Entry Only Warrants ” means Warrants that are to be held only by or on behalf of the Depository;

“ Business Day ” means any day other than Saturday, Sunday or a statutory or civic holiday, or any other day on which the banks are open for business in Montreal, Québec or Toronto, Ontario;

“ CDS Global Warrants ” means Warrants representing all or a portion of the aggregate number of Warrants issued in the name of the Depository represented by an Uncertificated Warrant, or if requested by the Depository or the Corporation, by a Warrant Certificate;

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“ Certificated Warrant ” means a Warrant evidenced by a writing or writings substantially in the form of Schedule “A”, attached hereto;

“ Common Shares ” means, subject to Article 4, fully paid and non-assessable Class A shares of the Corporation as presently constituted;

“ Counsel ” means a barrister or solicitor or a firm of barristers and solicitors retained by the Warrant Agent or retained by the Corporation and acceptable to the Warrant Agent, which may or may not be counsel for the Corporation;

“ Current Market Price ” of the Common Shares at any date means the weighted average of the trading price per Common Share for each day there was a closing price for the five consecutive Trading Days ending on (and including) the third Trading Day immediately prior to such date on the TSXV or if on such date the Common Shares are not listed on the TSXV, on such stock exchange upon which such Common Shares are listed and as selected by the directors, or, if such Common Shares are not listed on any stock exchange then on such over-the-counter market as may be selected for such purpose by the directors or, if not on any over-the-counter-market, as determined by the directors of the Corporation;

“ Depository ” means CDS Clearing and Depository Services Inc. or such other Person as is designated in writing by the Corporation to act as depository in respect of the Warrants;

“ Dividends ” means any dividends paid by the Corporation;

“ Effective Date ” means the date of this Indenture;

“ Exchange Rate ” means the number of Common Shares subject to the right of purchase under each Warrant;

“ Exercise Date ” means, in relation to the Warrants, the Business Day on which such Warrant is validly exercised or deemed to be validly exercised in accordance with Article 3 hereof;

“ Exercise Notice ” has the meaning set forth in Section 3.2(a);

“ Exercise Price ” at any time means the price at which a whole Common Share may be purchased by the exercise of a whole Warrant, which is initially US$1.50 per Common Share, payable in U.S. funds, subject to adjustment in accordance with the provisions of Article 4;

“ Expiry Date ” means, December 3, 2018;

“ Expiry Time ” means 5:00 p.m. (Montreal time) on the Expiry Date;

“ Extraordinary Resolution ” has the meaning set forth in 7.11;

“ Issue Date ” means December 3, 2013;

“ Internal Procedures ” means in respect of the making of any one or more entries to, changes in or deletions of any one or more entries in the register at any time (including without limitation, original issuance or registration of transfer of ownership) the minimum number of the Warrant Agent’s internal procedures customary at such time for the entry, change or deletion made to be complete under the operating procedures followed at the time by the Warrant Agent;

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“ NASDAQ ” means The Nasdaq Stock Market;

“ Over-Allotment Option ” has the meaning set forth on the first page of this Warrant Indenture;

“ person ” means an individual, body corporate, partnership, trust, warrant agent, executor, administrator, legal representative or any unincorporated organization;

“ register ” means the one set of records and accounts maintained by the Warrant Agent pursuant to Section 2.9;

“ Registered Warrantholders ” means the persons who are registered owners of Warrants as such names appear on the register, and for greater certainty, shall include the Depository as well as the holders of Uncertificated Warrants appearing on the register of the Warrant Agent;

“ Registration Statement ” means a registration statement filed with the SEC under the U.S. Securities Act registering the Common Shares issuable upon the exercise of the Warrants;

“ SEC ” means the United States Securities and Exchange Commission;

“ Shareholders ” means the holders of Common Shares;

“ Tax Act ” means the Income Tax Act (Canada) and the regulations thereunder;

“ this Warrant Indenture ”, “ this Indenture ”, “ this Agreement ”, “ hereto ” “ herein ”, “ hereby ”, “ hereof ” and similar expressions mean and refer to this indenture and any indenture, deed or instrument supplemental hereto; and the expressions “ Article ”, “ Section ”, “ subsection ” and “ paragraph ” followed by a number, letter or both mean and refer to the specified article, section, subsection or paragraph of this indenture;

“ Trading Day ” means, with respect to a stock exchange, a day on which such exchange is open for the transaction of business, and with respect to an over-the-counter market, means a day on which the TSXV or Toronto Stock Exchange is open for the transaction of business;

“ Transaction Instruction ” means a written order signed by the holder or the Depository, entitled to request that one or more actions be taken, or such other form as may be reasonably acceptable to the Warrant Agent, requesting one or more such actions to be taken in respect of an Uncertificated Warrant;

“ TSXV ” means the TSX Venture Exchange;

“ Uncertificated Warrant ” means any Warrant which is not a Certificated Warrant;

“ United States ” means the United States of America, its territories and possessions, any state of the United States, and the District of Columbia;

“ U.S. Person ” has the meaning given to such term in Regulation S under the U.S. Securities Act;

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“ U.S. Securities Act ” means the United States Securities Act of 1933 , as amended;

“ Warrants ” means the Common Share purchase warrants created by and authorized by and issuable under this Indenture, to be issued and countersigned hereunder in certificated form and/or held through the book entry registration system on a no certificate issued basis, entitling the holder thereof to purchase one Common Share (subject to adjustment as herein provided) at the Exercise Price prior to the Expiry Time or means the warrants issued and Authenticated hereunder, whether by way of Warrant Certificate or Uncertificated Warrant;

“ Warrant Agency ” means the principal office of the Warrant Agent in the City of Montreal, Québec, the City of Toronto, Ontario, or such other place as may be designated in accordance with Section 3.6;

“ Warrant Agent ” means Computershare Trust Company of Canada, in its capacity as warrant agent of the Warrants, or its successors from time to time;

“ Warrant Certificate ” means a certificate, substantially in the form set forth in Schedule “A” hereto, to evidence those Warrants that will be evidenced by a certificate;

“ Warrant Exercise Period ” means the period during which the Warrantholders may exercise the Warrants, commencing on the Issue Date and ending at the Expiry Time;

“ Warrantholders ”, or “ holders ” without reference to Warrants, means the warrantholders as, and in respect of Warrants registered in the name of the Depository, including owners of Warrants who beneficially hold securities entitlements in respect of the Warrants through a Book Entry Only Participant or means, at a particular time, the Persons entered in the register hereinafter mentioned as holders of Warrants outstanding at such time;

“ Warrantholders’ Request ” means an instrument signed in one or more counterparts by Registered Warrantholders entitled to acquire in the aggregate not less than 50% of the aggregate number of Common Shares which could be acquired pursuant to all Warrants then unexercised and outstanding, requesting the Warrant Agent to take some action or proceeding specified therein; and

“ written order of the Corporation ”, “ written request of the Corporation ”, “ written consent of the Corporation ” and “ certificate of the Corporation ” mean, respectively, a written order, request, consent and certificate signed in the name of the Corporation by any one director or officer of the Corporation and may consist of one or more instruments so executed.

Words importing the singular number or masculine gender shall include the plural number or the feminine or neuter genders, and vice versa.

The division of this Indenture into Articles and Sections, the provision of a Table of Contents and the insertion of headings are for convenience of reference only and shall not affect the construction or interpretation of this Indenture or of the Warrants.

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If any day on or before which any action or notice is required to be taken or given hereunder is not a Business Day, then such action or notice shall be required to be taken or given on or before the requisite time on the next succeeding day that is a Business Day.

Time shall be of the essence of this Indenture.

Whenever any amounts of money are referred to herein, such amounts shall be deemed to be in lawful money of Canada unless otherwise expressed. References to “ US$ ” are references to United States dollars.

This Indenture, the Warrants, the Warrant Certificates (including all documents relating thereto, which by common accord have been and will be drafted in English) shall be construed in accordance with the laws of the Province of Québec and the federal laws of Canada applicable therein and shall be treated in all respects as legally-binding contracts. Each of the parties hereto, which shall include the Warrantholders, irrevocably attorns to the exclusive jurisdiction of the courts of the Province of Québec with respect to all matters arising out of this Indenture and the transactions contemplated herein.

ARTICLE 2

ISSUE OF WARRANTS

A maximum of 18,400,000 Warrants are hereby created and authorized to be issued in accordance with the terms and conditions hereof. By written order of the Corporation, the Warrant Agent shall deliver Warrant Certificates to Registered Warrantholders and record the name of the Registered Warrantholders on the Warrant register. Registration of interests in Warrants held by the Depository may be evidenced by a position appearing on the register for Warrants of the Warrant Agent for an amount representing the aggregate number of such Warrants outstanding from time to time.

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Except as may be specifically provided herein, nothing in this Indenture or in the holding of a Warrant Certificate, entitlement to a Warrant or otherwise, shall, in itself, confer or be construed as conferring upon a Warrantholder any right or interest whatsoever as a Shareholder of the Corporation, including, but not limited to, the right to vote at, to receive notice of, or to attend, meetings of Shareholders or any other proceedings of the Corporation, or the right to Dividends and other allocations.

All Warrants shall rank equally and without preference over each other, whatever may be the actual date of issue thereof.

The Warrants may be issued in both certificated and uncertificated form. All Warrants issued in certificated form shall be evidenced by the Warrant Certificates (including all replacements issued in accordance with this Indenture), substantially in the form set out in Schedule “A” hereto, which shall be dated as of the Issue Date, shall bear such distinguishing letters and numbers as the Corporation may, with the approval of the Warrant Agent, prescribe, and shall be issuable in any denomination excluding fractions. All Warrants issued to the Depository may be in either a certificated or uncertificated form, such uncertificated form being evidenced by a book position on the register of Warrantholders to be maintained by the Warrant Agent in accordance with Section 2.6.

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following which Warrants for those holders requesting such shall be issued to the beneficial owners of such Warrants or their nominees as directed by the holder. The Corporation shall provide an Officer’s Certificate giving notice to the Warrant Agent of the occurrence of any event outlined in this Section 2.6(b).

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The register shall be available for inspection by the Corporation and or any Warrantholder during the Warrant Agent’s regular business hours on a Business Day and upon payment to the Warrant Agent of its reasonable fees. Any Warrantholder exercising such right of inspection shall first provide an affidavit in form satisfactory to the Corporation and the Warrant Agent stating the name and address of the Warrantholder and agreeing not to use the information therein except in connection with an effort to call a meeting of Warrantholders or to influence the voting of Warrantholders at any meeting of Warrantholders.

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and such transfer shall be duly noted in such register by the Warrant Agent. Upon compliance with such requirements, the Warrant Agent shall issue to the transferee of a Certificated Warrant (or it shall Authenticate an Uncertificated Warrant instead, upon request), a Warrant Certificate, and to the transferee of an Uncertificated Warrant, an Uncertificated Warrant (or it shall Authenticate and deliver a Certificated Warrant instead, upon request), representing the Warrants transferred and the transferee of a Book Entry Only Warrant shall be recorded through the relevant Book Entry Only Participant in accordance with the book entry registration system as the entitlement holder in respect of such Warrants.

All Warrant Certificates surrendered pursuant to Section 3.1 or Section 3.4 shall be cancelled by the Warrant Agent and upon such circumstances all such Uncertificated Warrants shall be deemed cancelled and so noted on the register by the Warrant Agent. Upon request by the Corporation, the Warrant Agent shall furnish to the Corporation a cancellation certificate identifying the Warrant Certificates so cancelled, the number of Warrants evidenced thereby, the number of Common Shares, if any, issued pursuant to such Warrants and the details of any Warrant Certificates issued in substitution or exchange for such Warrant Certificates cancelled, if applicable.

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ARTICLE 3

EXERCISE OF WARRANTS

Subject to the provisions hereof, each Registered Warrantholder may exercise the right conferred on such holder to subscribe for and purchase one Common Share for each Warrant after the Issue Date and prior to the Expiry Time and in accordance with the conditions herein.

Notwithstanding any provision to the contrary contained in this Indenture, no Warrantholder may exercise any Warrant at any time when no Registration Statement is effective under the U.S. Securities Act, unless an exemption from the registration requirements of the U.S. Securities Act is available and such holder provides evidence of the availability of such exemption reasonably satisfactory to the Corporation and the Warrant Agent. If no Registration Statement is effective under the U.S. Securities Act at any time prior to the Expiry Time, such Warrantholder shall be notified forthwith by the Warrant Agent that such Warrantholder is entitled to a Cashless Exercise, in whole or in part, in accordance with Section 3.4.

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Notwithstanding anything herein contained, Common Shares will be issued upon exercise of a Warrant only in compliance with the securities laws of any applicable jurisdiction, including without limitation the Applicable Securities Laws, and, without limiting the generality of the foregoing, the Corporation will direct the Warrant Agent to legend any certificates representing the Common Shares if, in the opinion of counsel to the Corporation acting reasonably, such legend is necessary in order to avoid a violation of the Applicable Securities Laws or to comply with the requirements of any stock exchange on which the Common Shares are listed; provided that if, at any time, in the opinion of counsel to the Corporation, acting reasonably, such legends are no longer necessary in order to avoid a violation of any such laws, or the holder of any such legended certificate, at his or her expense, provides the Corporation with evidence in form and substance reasonably satisfactory to the Corporation (which may include an opinion of Counsel of recognized standing in form and substance reasonably satisfactory to the Corporation) to the effect that such holder is entitled to sell or otherwise transfer such Common Shares in a transaction in which such legends are not required, such legended certificates may thereafter be surrendered to the Warrant Agent in exchange for a certificate which does not bear such legends.

The Warrant Agent shall be entitled to assume that Common Shares may be issued pursuant to the exercise of any Warrant without violating any Applicable Securities Laws and without legending the certificate representing the Common Shares unless the Warrant Agent has received notice in writing from the Corporation stating otherwise and setting forth the restrictions on the exercise of the Warrants and any legend the certificates representing the Common Shares should bear.

For greater certainty, should no Registration Statement be effective under the U.S. Securities Act and no exemption from the registration requirements of the U.S. Securities Act be available such that a Warrantholder may receive freely tradable Common Shares upon exercise of Warrants, the Corporation shall permit the Cashless Exercise of the Warrants held by Warrantholders as set forth in Section 3.4 and shall not be permitted to issue legended Common Shares in lieu thereof.

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If any of the Common Shares subscribed for are to be issued to a person or persons other than the Registered Warrantholder, the Registered Warrantholder shall execute the form of transfer and will comply with such reasonable requirements as the Warrant Agent may stipulate and will pay to the Corporation or the Warrant Agent on behalf of the Corporation, all applicable transfer or similar taxes and the Corporation will not be required to issue or deliver certificates evidencing Common Shares or issue Common Shares in uncertificated form unless or until such Warrantholder shall have paid to the Corporation or the Warrant Agent on behalf of the Corporation, the amount of such tax or shall have established to the satisfaction of the Corporation and the Warrant Agent that such tax has been paid or that no tax is due.

To facilitate the exchange, transfer or exercise of Warrants and compliance with such other terms and conditions hereof as may be required, the Corporation has appointed the Warrant Agency, as the agency at which Warrants may be surrendered for exchange or transfer or at which Warrants may be exercised and the Warrant Agent has accepted such appointment. The Corporation may from time to time designate alternate or additional places as the Warrant Agency (subject to the Warrant Agent’s prior approval) and will give notice to the Warrant Agent of any proposed change of the Warrant Agency. Branch registers shall also be kept at such other place or places, if any, as the Corporation, with the approval of the Warrant Agent, may designate. The Warrant Agent will from time to time when requested to do so by the Corporation or any Registered Warrantholder, upon payment of the Warrant Agent’s reasonable charges, furnish a list of the names and addresses of Registered Warrantholders showing the number of Warrants held by each such Registered Warrantholder.

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Immediately after the Expiry Time, all rights under any Warrant in respect of which the right of acquisition provided for herein shall not have been exercised shall cease and terminate and each Warrant shall be void and of no further force or effect.

ARTICLE 4

ADJUSTMENT OF NUMBER OF COMMON SHARES AND EXERCISE PRICE

The subscription rights in effect under the Warrants for Common Shares issuable upon the exercise of the Warrants shall be subject to adjustment from time to time as follows:

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the Exercise Price in effect on the effective date of such subdivision, re-division, change, reduction, combination, consolidation or on the record date of such distribution, as the case may be, shall in the case of the events referred to in (i) or (iii) above be decreased in proportion to the number of outstanding Common Shares resulting from such subdivision, re-division, change or distribution, or shall, in the case of the events referred to in (ii) above, be increased in proportion to the number of outstanding Common Shares resulting from such reduction, combination or consolidation. Such adjustment shall be made successively whenever any event referred to in this Section 4.1(a) shall occur. Upon any adjustment of the Exercise Price pursuant to Section 4.1(a), the Exchange Rate shall be contemporaneously adjusted by multiplying the number of Common Shares theretofore obtainable on the exercise thereof by a fraction of which the numerator shall be the Exercise Price in effect immediately prior to such adjustment and the denominator shall be the Exercise Price resulting from such adjustment;

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All Common Shares or shares of any class or other securities, which a Registered Warrantholder is at the time in question entitled to receive on the exercise of its Warrant, whether or not as a result of adjustments made pursuant to this Article 4, shall, for the purposes of the interpretation of this Indenture, be deemed to be Common Shares which such Registered Warrantholder is entitled to acquire pursuant to such Warrant.

Notwithstanding anything in this Article 4, no adjustment shall be made in the acquisition rights attached to the Warrants if the issue of Common Shares is being made pursuant to this Indenture or in connection with (a) any share incentive plan or restricted share plan or share purchase plan in force from time to time for directors, officers, employees, consultants or other service providers of the Corporation; or (b) the satisfaction of existing instruments issued at the date hereof.

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In the event of any question arising with respect to the adjustments provided for in this Article 4 such question shall be conclusively determined by an independent firm of chartered accountants other than the Auditors, who shall have access to all necessary records of the Corporation, and such determination shall be binding upon the Corporation, the Warrant Agent, all holders and all other persons interested therein.

As a condition precedent to the taking of any action which would require an adjustment in any of the acquisition rights pursuant to any of the Warrants, including the number of Common Shares which are to be received upon the exercise thereof, the Corporation shall take any action which may, in the opinion of Counsel, be necessary in order that the Corporation has unissued and reserved in its authorized capital and may validly and legally issue as fully paid and non-assessable all the Common Shares which the holders of such Warrants are entitled to receive on the full exercise thereof in accordance with the provisions hereof.

The Corporation shall from time to time immediately after the occurrence of any event which requires an adjustment or readjustment as provided in Article 4, deliver a certificate of the Corporation to the Warrant Agent specifying the nature of the event requiring the same and the amount of the adjustment or readjustment necessitated thereby and setting forth in reasonable detail the method of calculation and the facts upon which such calculation is based, which certificate shall be supported by a certificate of the Corporation’s Auditors verifying such calculation. The Warrant Agent shall rely, and shall be protected in so doing, upon the certificate of the Corporation or of the Corporation’s Auditor and any other document filed by the Corporation pursuant to this Article 4 for all purposes.

The Corporation covenants with the Warrant Agent that, so long as any Warrant remains outstanding, it will give notice to the Warrant Agent and to the Registered Warrantholders of its intention to fix a record date that is prior to the Expiry Date for any matter for which an adjustment may be required pursuant to Section 4.1. Such notice shall specify the particulars of such event and the record date for such event, provided that the Corporation shall only be required to specify in the notice such particulars of the event as shall have been fixed and determined on the date on which the notice is given. The notice shall be given in each case not less than 14 days prior to such applicable record date. If notice has been given and the adjustment is not then determinable, the Corporation shall promptly, after the adjustment is determinable, file with the Warrant Agent a computation of the adjustment and give notice to the Registered Warrantholders of such adjustment computation.

The Corporation covenants with the Warrant Agent that it will not close its transfer books or take any other corporate action which might deprive the Registered Warrantholder of the opportunity to exercise its right of acquisition pursuant thereto during the period of 14 days after the giving of the certificate or notices set forth in Section 4.6 and Section 4.7.

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If the Corporation, after the date hereof, shall take any action affecting the Common Shares other than action described in Section 4.1, which in the reasonable opinion of the directors of the Corporation would materially affect the rights of Registered Warrantholders, the Exercise Price and/or the Exchange Rate, the number of Common Shares which may be acquired upon exercise of the Warrants shall be adjusted in such manner and at such time, by action of the directors of the Corporation, acting reasonably, in their sole discretion as they may determine to be equitable to the Registered Warrantholders in the circumstances, provided that no such adjustment will be made unless any requisite prior approval of any stock exchange on which the Common Shares are listed for trading has been obtained.

The Warrant Agent shall not:

No adjustments shall be made pursuant to this Article 4 if the Registered Warrantholders are entitled to participate in any event described in this Article 4 on the same terms, mutatis mutandis , as if the Registered Warrantholders had exercised their Warrants prior to, or on the effective date or record date of, such event.

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ARTICLE 5

RIGHTS OF THE CORPORATION AND COVENANTS

Subject to compliance with Applicable Securities Laws and approval of applicable regulatory authorities, the Corporation may from time to time purchase by private contract or otherwise any of the Warrants. Any such purchase shall be made at the lowest price or prices at which, in the opinion of the directors of the Corporation, such Warrants are then obtainable, plus reasonable costs of purchase, and may be made in such manner, from such persons and on such other terms as the Corporation, in its sole discretion, may determine. In the case of Certificated Warrants, Warrant Certificates representing the Warrants purchased pursuant to this Section 5.1 shall forthwith be delivered to and cancelled by the Warrant Agent. In the case of Uncertificated Warrants, the Warrants purchased pursuant to this Section 5.1 shall be reflected accordingly in accordance with procedures prescribed by the Depository under the book entry registration system. No Warrants shall be issued in replacement thereof.

The Corporation covenants with the Warrant Agent for the benefit of the Warrant Agent and the Warrantholders that so long as any Warrants remain outstanding:

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The Corporation covenants that it will pay to the Warrant Agent from time to time reasonable remuneration for its services hereunder and will pay or reimburse the Warrant Agent upon its request for all reasonable expenses, disbursements and advances incurred or made by the Warrant Agent in the administration or execution of the trusts hereby created (including the reasonable compensation and the disbursements of its Counsel and all other advisers and assistants not regularly in its employ) both before any default hereunder and thereafter until all duties of the Warrant Agent hereunder shall be finally and fully performed. Any amount owing hereunder and remaining unpaid after 30 days from the invoice date will bear interest at the then current rate charged by the Warrant Agent against unpaid invoices and shall be payable upon demand. This Section shall survive the resignation of the Warrant Agent and/ or the termination of this Indenture.

If the Corporation shall fail to perform any of its covenants contained in this Indenture, the Warrant Agent may notify the Registered Warrantholders of such failure on the part of the Corporation or may itself perform any of the covenants capable of being performed by it but, subject to Section 9.2, shall be under no obligation to perform said covenants or to notify the Registered Warrantholders of such performance by it. All sums expended or advanced by the Warrant Agent in so doing shall be repayable as provided in Section 5.3. No such performance, expenditure or advance by the Warrant Agent shall relieve the Corporation of any default hereunder or of its continuing obligations under the covenants herein contained.

The Corporation covenants and agrees that it is duly authorized to create and issue the Warrants to be issued hereunder and that the Warrants, when issued and Authenticated as herein provided, will be valid and enforceable against the Corporation in accordance with the provisions hereof and the terms hereof and that, subject to the provisions of this Indenture, the Corporation will cause the Common Shares from time to time acquired upon exercise of Warrants issued under this Indenture to be duly issued and delivered in accordance with the terms of this Indenture.

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ARTICLE 6

ENFORCEMENT

All or any of the rights conferred upon any Registered Warrantholder by any of the terms of this Indenture may be enforced by the Registered Warrantholder by appropriate proceedings but without prejudice to the right which is hereby conferred upon the Warrant Agent to proceed in its own name to enforce each and all of the provisions herein contained for the benefit of the Registered Warrantholders.

The Corporation shall have the right to enforce full payment of the Exercise Price of all Common Shares issued by the Warrant Agent to a Registered Warrantholder hereunder and shall be entitled to demand such payment from the Registered Warrantholder or alternatively to instruct the Warrant Agent to cancel the share certificates and amend the securities register accordingly.

The Warrant Agent and the Warrantholders hereby waive and release any right, cause of action or remedy now or hereafter existing in any jurisdiction against any incorporator or any past, present or future shareholder, trustee, employee or agent of the Corporation or any successor Corporation on any covenant, agreement, representation or warranty by the Corporation herein.

Upon the happening of any default hereunder:

provided that no delay or omission of the Warrant Agent or of the Registered Warrantholders to exercise any right or power accruing upon any default shall impair any such right or power or shall be construed to be a waiver of any such default or acquiescence therein and provided further that no act or omission either of the Warrant Agent or of the Registered Warrantholders in the premises shall extend to or be taken in any manner whatsoever to affect any subsequent default hereunder of the rights resulting therefrom.

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ARTICLE 7

MEETINGS OF REGISTERED WARRANTHOLDERS

The Warrant Agent may at any time and from time to time, and shall on receipt of a written request of the Corporation or of a Warrantholders’ Request and upon being indemnified and funded to its reasonable satisfaction by the Corporation or by the Registered Warrantholders signing such Warrantholders’ Request against the costs which may be incurred in connection with the calling and holding of such meeting, convene a meeting of the Registered Warrantholders. If the Warrant Agent fails to so call a meeting within seven days after receipt of such written request of the Corporation or such Warrantholders’ Request and the indemnity and funding given as aforesaid, the Corporation or such Registered Warrantholders, as the case may be, may convene such meeting. Every such meeting shall be held in the City of Montreal, Québec or at such other place as may be approved or determined by the Warrant Agent.

At least 21 days’ prior written notice of any meeting of Registered Warrantholders shall be given to the Registered Warrantholders in the manner provided for in Section 10.2 and a copy of such notice shall be sent by mail to the Warrant Agent (unless the meeting has been called by the Warrant Agent) and to the Corporation (unless the meeting has been called by the Corporation). Such notice shall state the time when and the place where the meeting is to be held, shall state briefly the general nature of the business to be transacted thereat and shall contain such information as is reasonably necessary to enable the Registered Warrantholders to make a reasoned decision on the matter, but it shall not be necessary for any such notice to set out the terms of any resolution to be proposed or any of the provisions of this Section 7.2.

An individual (who need not be a Registered Warrantholder) designated in writing by the Warrant Agent shall be chairman of the meeting and if no individual is so designated, or if the individual so designated is not present within fifteen minutes from the time fixed for the holding of the meeting, the Registered Warrantholders present in person or by proxy shall choose an individual present to be chairman.

Subject to the provisions of Section 7.11, at any meeting of the Registered Warrantholders a quorum shall consist of Registered Warrantholder(s) present in person or by proxy and entitled to purchase at least 20% of the aggregate number of Common Shares which could be acquired pursuant to all the then-outstanding Warrants. If a quorum of the Registered Warrantholders shall not be present within thirty minutes from the time fixed for holding any meeting, the meeting, if summoned by Registered Warrantholders or on a Warrantholders’ Request, shall be dissolved; but in any other case the meeting shall be adjourned to the same day in the next week (unless such day is not a Business Day, in which case it shall be adjourned to

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the next following Business Day) at the same time and place and no notice of the adjournment need be given. Any business may be brought before or dealt with at an adjourned meeting which might have been dealt with at the original meeting in accordance with the notice calling the same. No business shall be transacted at any meeting unless a quorum be present at the commencement of business. At the adjourned meeting the Registered Warrantholders present in person or by proxy shall form a quorum and may transact the business for which the meeting was originally convened, notwithstanding that they may not be entitled to acquire at least 20% of the aggregate number of Common Shares which may be acquired pursuant to all then outstanding Warrants.

The chairman of any meeting at which a quorum of the Registered Warrantholders is present may, with the consent of the meeting, adjourn any such meeting, and no notice of such adjournment need be given except such notice, if any, as the meeting may prescribe.

Every question submitted to a meeting shall be decided in the first place by a majority of the votes given on a show of hands except that votes on an Extraordinary Resolution shall be given in the manner hereinafter provided. At any such meeting, unless a poll is duly demanded as herein provided, a declaration by the chairman that a resolution has been carried or carried unanimously or by a particular majority or lost or not carried by a particular majority shall be conclusive evidence of the fact.

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The Corporation and the Warrant Agent, by their respective directors, officers agents, and employees and the Counsel for the Corporation and for the Warrant Agent may attend any meeting of the Registered Warrantholders.

In addition to all other powers conferred upon them by any other provisions of this Indenture or by law, the Registered Warrantholders at a meeting shall, subject to the provisions of Section 7.11, have the power exercisable from time to time by Extraordinary Resolution:

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Any one or more of the powers or any combination of the powers in this Indenture stated to be exercisable by the Registered Warrantholders by Extraordinary Resolution or otherwise may be exercised from time to time and the exercise of any one or more of such powers or any combination of powers from time to time shall not be deemed to exhaust the right of the Registered Warrantholders to exercise such power or powers or combination of powers then or thereafter from time to time.

Minutes of all resolutions and proceedings at every meeting of Registered Warrantholders shall be made and duly entered in books to be provided from time to time for that purpose by the Warrant Agent at the expense of the Corporation, and any such minutes as aforesaid, if signed by the chairman or the secretary of the meeting at which such resolutions were passed or proceedings had shall be prima facie evidence of the matters therein stated and, until the contrary is proved, every such meeting in respect of the proceedings of which minutes shall have been made shall be deemed to have been duly convened and held, and all resolutions passed thereat or proceedings taken shall be deemed to have been duly passed and taken.

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All actions which may be taken and all powers that may be exercised by the Registered Warrantholders at a meeting held as provided in this Article 7 may also be taken and exercised by Registered Warrantholders holding at least 66  ² ⁄ ₃ % of the aggregate number of Common Shares that could be acquired by an instrument in writing signed in one or more counterparts by such Registered Warrantholders in person or by attorney duly appointed in writing, and the expression “ Extraordinary Resolution ” when used in this Indenture shall include an instrument so signed.

Every resolution and every Extraordinary Resolution passed in accordance with the provisions of this Article 7 at a meeting of Registered Warrantholders shall be binding upon all the Warrantholders, whether present at or absent from such meeting, and every instrument in writing signed by Registered Warrantholders in accordance with Section 7.14 shall be binding upon all the Warrantholders, whether signatories thereto or not, and each and every Warrantholder and the Warrant Agent (subject to the provisions for indemnity herein contained) shall be bound to give effect accordingly to every such resolution and instrument in writing.

In determining whether Registered Warrantholders holding Warrants evidencing the entitlement to acquire the required number of Common Shares are present at a meeting of Registered Warrantholders for the purpose of determining a quorum or have concurred in any consent, waiver, Extraordinary Resolution, Warrantholders’ Request or other action under this Indenture, Warrants owned legally or beneficially by the Corporation shall be disregarded in accordance with the provisions of Section 10.7.

ARTICLE 8

SUPPLEMENTAL INDENTURES

From time to time, the Corporation (when authorized by action of the directors) and the Warrant Agent may, subject to the provisions hereof and they shall, when so directed in accordance with the provisions hereof, execute and deliver by their proper officers, indentures or instruments supplemental hereto, which thereafter shall form part hereof, for any one or more or all of the following purposes:

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In the case of the consolidation, amalgamation, arrangement, merger or transfer of the undertaking or assets of the Corporation as an entirety or substantially as an entirety to or with another entity (“ successor entity ”), the successor entity resulting from such consolidation, amalgamation, arrangement, merger or transfer (if not the Corporation) shall expressly assume, by supplemental indenture satisfactory in form to the Warrant Agent and executed and delivered to the Warrant Agent, the due and punctual performance and observance of each and every covenant and condition of this Indenture to be performed and observed by the Corporation.

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ARTICLE 9

CONCERNING THE WARRANT AGENT

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The Warrant Agent shall have power to institute and to maintain such actions and proceedings as it may consider necessary or expedient to preserve, protect or enforce its interests and the interests of the Registered Warrantholders.

The Warrant Agent shall not be required to give any bond or security in respect of the execution of the agency and powers of this Indenture or otherwise in respect of the premises.

By way of supplement to the provisions of any law for the time being relating to the Warrant Agent it is expressly declared and agreed as follows:

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The Warrant Agent hereby accepts the agency in this Indenture declared and provided for and agrees to perform the same upon the terms and conditions herein set forth and to hold and exercise the rights, privileges and benefits conferred upon it hereby in trust for and on behalf of the persons who become Warrant holders from time to time.

The Warrant Agent and any person related to the Warrant Agent shall not be appointed a receiver, a receiver and manager or liquidator of all or any part of the assets or undertaking of the Corporation.

The Warrant Agent shall not be bound to give any notice or do or take any act, action or proceeding by virtue of the powers conferred on it hereby unless and until it shall have been

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required so to do under the terms hereof; nor shall the Warrant Agent be required to take notice of any default hereunder, unless and until notified in writing of such default, which notice shall distinctly specify the default desired to be brought to the attention of the Warrant Agent and the Warrant Agent shall promptly provide the Warrantholder with any such notice and in the absence of any such notice the Warrant Agent may for all purposes of this Indenture conclusively assume that no default has been made in the observance or performance of any of the representations, warranties, covenants, agreements or conditions contained herein. Any such notice shall in no way limit any discretion herein given to the Warrant Agent to determine whether or not the Warrant Agent shall take action with respect to any default.

The Corporation acknowledges that the Warrant Agent may, in the course of providing services hereunder, collect or receive financial and other personal information about such parties and/or their representatives, as individuals, or about other individuals related to the subject matter hereof, and use such information for the following purposes:

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The Corporation acknowledges and agrees that the Warrant Agent may receive, collect, use and disclose personal information provided to it or acquired by it in the course of its acting as agent hereunder for the purposes described above and, generally, in the manner and on the terms described in its Privacy Code, which the Warrant Agent shall make available on its website or upon request, including revisions thereto. Some of this personal information may be transferred to servicers in the United States of America for data processing and /or storage. Further, the Corporation agrees that it shall not provide or cause to be provided to the Warrant Agent any personal information relating to an individual who is not a party to this Indenture unless the Corporation has assured itself that such individual understands and has consented to the aforementioned terms, uses and disclosures.

The Corporation represents and warrants that it has reporting obligations with the SEC and has delivered to the Warrant Agent an Officers’ Certificate certifying such “ reporting issuer ” status and other information as the Warrant Agent has requested, including, but not limited to, the Central Index Key that has been assigned for filing purposes. Should the Corporation cease to have an obligation to file reports with the SEC, the Corporation covenants to deliver to the Warrant Agent an Officers’ Certificate (in a form provided by the Warrant Agent) certifying a change in “ reporting issuer ” status and such other information as the Warrant Agent may require at such given time. The Corporation understands that the Warrant Agent is relying upon the foregoing representation, warranty and covenants in order to meet certain SEC obligations with respect to those clients who are filing with the SEC.

ARTICLE 10

GENERAL

Acasti Pharma Inc.

545 Promenade du Centropolis, Suite 100, Laval, Québec, Canada, H7T 0A3

Attention: Chief Financial Officer

Telecopy: (450) 687-2272

Computershare Trust Company of Canada

1500 University Street, 7 ^th Floor, Montréal, Québec, Canada, H3A 3S8

Attention: General Manager, Corporate Trust

Telecopy: (514) 982-7677

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and any such notice delivered in accordance with the foregoing shall be deemed to have been received and given on the date of delivery or, if mailed, on the fifth Business Day following the date of mailing such notice or, if telecopied, on the next Business Day following the date of transmission.

The Corporation and the Warrant Agent may deem and treat the Registered Warrantholders as the absolute owner thereof for all purposes, and the Corporation and the Warrant Agent shall not be affected by any notice or knowledge to the contrary except where the Corporation or the Warrant Agent is required to take notice by statute or by order of a court of

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competent jurisdiction. The receipt of any such Registered Warrantholder of the Common Shares which may be acquired pursuant thereto shall be a good discharge to the Corporation and the Warrant Agent for the same and neither the Corporation nor the Warrant Agent shall be bound to inquire into the title of any such holder except where the Corporation or the Warrant Agent is required to take notice by statute or by order of a court of competent jurisdiction.

This Indenture may be executed in several counterparts, each of which when so executed shall be deemed to be an original and such counterparts together shall constitute one and the same instrument and notwithstanding their date of execution they shall be deemed to be dated as of the date hereof.

Upon the earlier of:

and if all certificates or other entry on the register representing Common Shares required to be issued in compliance with the provisions hereof have been issued and delivered hereunder or to the Warrant Agent in accordance with such provisions, this Indenture shall cease to be of further effect and the Warrant Agent, on demand of and at the cost and expense of the Corporation and upon delivery to the Warrant Agent of a certificate of the Corporation stating that all conditions precedent to the satisfaction and discharge of this Indenture have been complied with, shall execute proper instruments acknowledging satisfaction of and discharging this Indenture. Notwithstanding the foregoing, the indemnities provided to the Warrant Agent by the Corporation hereunder shall remain in full force and effect and survive the termination of this Indenture.

Nothing in this Indenture or in the Warrants, expressed or implied, shall give or be construed to give to any person other than the parties hereto and the Registered Warrantholders, as the case may be, any legal or equitable right, remedy or claim under this Indenture, or under any covenant or provision herein or therein contained, all such covenants and provisions being for the sole benefit of the parties hereto and the Registered Warrantholders.

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For the purpose of disregarding any Warrants owned legally or beneficially by the Corporation in Section 7.16, the Corporation shall provide to the Warrant Agent, from time to time, a certificate of the Corporation setting forth as at the date of such certificate:

If, in any jurisdiction, any provision of this Indenture or its application to any party or circumstance is restricted, prohibited or unenforceable, such provision will, as to such jurisdiction, be ineffective only to the extent of such restriction, prohibition or unenforceability without invalidating the remaining provisions of this Indenture and without affecting the validity or enforceability of such provision in any other jurisdiction or without affecting its application to other parties or circumstances.

No party shall be liable to the other, or held in breach of this Indenture, if prevented, hindered, or delayed in the performance or observance of any provision contained herein by reason of act of God, riots, terrorism, acts of war, epidemics, governmental action or judicial order, earthquakes, or any other similar causes (including, but not limited to, mechanical, electronic or communication interruptions, disruptions or failures). Performance times under this Indenture shall be extended for a period of time equivalent to the time lost because of any delay that is excusable under this Section.

Neither of the parties hereto may assign its rights or interest under this Indenture, except as provided in Section 9.8 in the case of the Warrant Agent, or as provided in Section 8.2 in the case of the Corporation. Subject thereto, this Indenture shall enure to the benefit of and be binding upon the parties hereto and their respective successors and permitted assigns.

Should a holder of Warrants exercise any legal, statutory, contractual or other right of withdrawal or rescission that may be available to it, and the holder’s funds which were paid on exercise have already been released to the Corporation by the Warrant Agent, the Warrant Agent shall not be responsible for ensuring the exercise is cancelled and a refund is paid back to the holder. In such cases, the holder shall seek a refund directly from the Corporation and subsequently, the Corporation, upon surrender to the Corporation or the Warrant Agent of any Common Shares that may have been issued, or such other procedure as agreed to by the parties hereto, shall instruct the Warrant Agent in writing, to cancel the exercise transaction and any

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such Common Shares on the register, which may have already been issued upon the Warrant exercise. In the event that any payment is received from the Corporation by virtue of the holder being a shareholder for such Warrants that were subsequently rescinded, such payment must be returned by the Corporation to the holder and the Warrant Agent shall not be under any duty or obligation to take any steps to ensure or enforce that the funds are returned pursuant to this section, nor shall the Warrant Agent be in any other way responsible in the event that any payment is not delivered or received pursuant to this section. Notwithstanding the foregoing, in the event that the Corporation provides the refund to the Warrant Agent for distribution to the holder, the Warrant Agent shall return such funds to the holder as soon as reasonably practicable, and in so doing, the Warrant Agent shall incur no liability with respect to the delivery or non-delivery of any such funds.

The parties hereto confirm their express wish that this Indenture and all documents and agreements directly or indirectly relating thereto be drawn up in the English language. Notwithstanding such express wish, the parties agree that any such document or agreement, or any part thereof or of this Indenture, may be drawn up in the French language. Les parties aux présentes conferment leur volunté expresse que la présente convention ainsi que tous les documents et conventions s’y rattachant directement ou indirectement soient rédigés en anglais. Nonobstant cette volunté expresse, les parties aux présentes conviennent que la présente convention ainsi que tous les documents et conventions s’y rattachant directement ou indirectement, ou toute partie de ceux-ci, puissent être rédigés en français.

[Signature page follows]

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IN WITNESS WHEREOF the parties hereto have executed this Indenture under the hands of their proper officers in that behalf as of the date first written above.

Schedule “A”

CUSIP: 00430K147

ISIN: CA00430K1479

THIS IS TO CERTIFY THAT , for value received,

(the “ Warrantholder ”) is the registered holder of the number of common share purchase warrants (the “ Warrants ”) of Acasti Pharma Inc. (the “ Corporation ”) specified above, and is entitled, on exercise of these Warrants upon and subject to the terms and conditions set forth herein and in the Warrant Indenture hereinafter referred to, to purchase at any time before 5:00 p.m. (Montreal time) (the “ Expiry Time ”) on December 3, 2018 (the “ Expiry Date ”), one fully paid and non-assessable common share without par value in the capital of the Corporation as constituted on the date hereof (a “ Common Share ”) for each Warrant subject to adjustment in accordance with the terms of the Warrant Indenture.

The Warrants evidenced hereby are exercisable at or before 5:00 p.m. (Montreal time) on December 3, 2018 after which time the warrants evidenced hereby shall be deemed to be void and of no further force or effect.

The right to purchase Common Shares may only be exercised by the holder within the time set forth above by:

The surrender of this Warrant Certificate, the duly completed Exercise Form and payment as provided above will be deemed to have been effected only on personal delivery thereof to, or if sent by mail or other means of transmission on actual receipt thereof by, the Warrant Agent at its principal office as set out above.

Subject to adjustment thereof in the events and in the manner set forth in the Warrant Indenture hereinafter referred to, the exercise price payable for each Common Share upon the exercise of the Warrants shall be US$1.50 per Common Share (the “ Exercise Price ”).

Certificates for the Common Shares subscribed for will be mailed to the persons specified in the Exercise Form at their respective addresses specified therein or, if so specified in the Exercise Form, delivered to such persons at the office where this Warrant Certificate is surrendered. If fewer Common Shares are purchased than the number that can be purchased pursuant to this Warrant Certificate, the holder hereof will be entitled to receive without charge a new Warrant Certificate in respect of the balance of the Common Shares not so purchased. No fractional Common Shares will be issued upon exercise of any Warrant.

This Warrant Certificate evidences Warrants of the Corporation issued or issuable under the provisions of a warrant indenture (which indenture together with all other instruments supplemental or ancillary thereto is herein referred to as the “ Warrant Indenture ”) dated as of December 3, 2013 between the Corporation and Computershare Trust Company of Canada, as Warrant Agent, to which Warrant Indenture reference is hereby made for particulars of the rights of the holders of Warrants, the Corporation and the Warrant Agent in respect thereof and the terms and conditions on which the Warrants are issued and held, all to the same effect as if the provisions of the Warrant Indenture were herein set forth, to all of which the holder, by acceptance hereof, assents. The Corporation will furnish to the holder, on request and without charge, a copy of the Warrant Indenture.

The Warrants evidenced hereby shall not be exercised by any person during any time that no registration statement under the U.S. Securities Act registering the Common Shares issuable upon the exercise of the Warrants evidenced hereby is effective, unless an exemption from the registration requirements to the U.S. Securities Act is available and such holder provides evidence of the availability of such exemption reasonably satisfactory to the Corporation and the Warrant Agent. During such time and prior to the Expiry Time, any person holding such Warrants shall have the right to provide notice to the Corporation of their intent to exercise, at which time the Corporation shall permit such holder to exercise on a cashless basis such Warrants (provided that the Common Shares issued pursuant to such cashless exercise shall not be subject to any transfer restrictions in the United States or Canada).

On presentation at the principal office of the Warrant Agent as set out above, subject to the provisions of the Warrant Indenture and on compliance with the reasonable requirements of the Warrant Agent, one or more Warrant Certificates may be exchanged for one or more Warrant Certificates entitling the holder thereof to purchase in the aggregate an equal number of Common Shares as are purchasable under the Warrant Certificate(s) so exchanged.

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The Warrant Indenture contains provisions for the adjustment of the Exercise Price per Common Share upon the exercise of Warrants and the number of Common Shares issuable upon the exercise of Warrants in the events and in the manner set forth therein.

The Warrant Indenture also contains provisions making binding on all holders of Warrants outstanding thereunder resolutions passed at meetings of holders of Warrants held in accordance with the provisions of the Warrant Indenture and instruments in writing signed by holders of Warrants entitled to purchase a specific majority of the Common Shares that can be purchased pursuant to such Warrants.

Nothing contained in this Warrant Certificate, the Warrant Indenture or elsewhere shall be construed as conferring upon the holder hereof any right or interest whatsoever as a holder of Common Shares or any other right or interest except as herein and in the Warrant Indenture expressly provided. In the event of any discrepancy between anything contained in this Warrant Certificate and the terms and conditions of the Warrant Indenture, the terms and conditions of the Warrant Indenture shall govern.

Warrants may only be transferred in compliance with the conditions of the Warrant Indenture on the register to be kept by the Warrant Agent in Montreal, Québec, or such other registrar as the Corporation, with the approval of the Warrant Agent, may appoint at such other place or places, if any, as may be designated, upon surrender of this Warrant Certificate to the Warrant Agent or other registrar accompanied by a written instrument of transfer in form and execution satisfactory to the Warrant Agent or other registrar and upon compliance with the conditions prescribed in the Warrant Indenture and with such reasonable requirements as the Warrant Agent or other registrar may prescribe and upon the transfer being duly noted thereon by the Warrant Agent or other registrar. Time is of the essence hereof.

This Warrant Certificate will not be valid for any purpose until it has been countersigned by or on behalf of the Warrant Agent from time to time under the Warrant Indenture.

The parties hereto have declared that they have required that these presents and all other documents related hereto be in the English language. Les parties aux présentes déclarent qu’elles ont exigé que la présente convention, de même que tous les documents s’y rapportant, soient rédigés en anglais .

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IN WITNESS WHEREOF the Corporation has caused this Warrant Certificate to be duly executed as of                     , 2013.

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FORM OF TRANSFER

Computershare Trust Company of Canada

FOR VALUE RECEIVED the undersigned hereby sells, assigns and transfers to

(print name and address)

the Warrants represented by this Warrants Certificate and hereby irrevocable constitutes and appoints                      as its attorney with full power of substitution to transfer the said securities on the appropriate register of the Warrant Agent.

CERTAIN REQUIREMENTS RELATING TO TRANSFERS – READ CAREFULLY

The signature(s) of the transferor(s) must correspond with the name(s) as written upon the face of this certificate(s), in every particular, without alteration or enlargement, or any change whatsoever. The signature(s) on this form must be guaranteed in accordance with the transfer agent’s then current guidelines and requirements at the time of transfer. Notarized or witnessed signatures are not acceptable as guaranteed signatures. As at the time of transfer, you may choose one of the following methods (although subject to change in accordance with industry practice and standards):

Canada and the USA: A Medallion Signature Guarantee obtained from a member of an acceptable Medallion Signature Guarantee Program (STAMP, SEMP, NYSE MSP). Many commercial banks, savings banks, credit unions, and all broker dealers participate in a Medallion Signature Guarantee Program. The Guarantor must affix a stamp bearing the actual words “ Medallion Guaranteed ”, with the correct prefix covering the face value of the certificate.

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Canada: A Signature Guarantee obtained from the Guarantor must affix a stamp bearing the actual words “ Signature Guaranteed ”. Signature Guarantees are not accepted from Treasury Branches, Credit Unions or Caisse Populaires unless they are members of a Medallion Signature Guarantee Program. For corporate holders, corporate signing resolutions, including certificate of incumbency, are also required to accompany the transfer, unless there is a “ Signature & Authority to Sign Guarantee ” Stamp affixed to the transfer (as opposed to a “ Signature Guarantee ” Stamp) obtained from an authorized officer of a major Canadian Schedule 1 chartered bank.

Outside North America: For holders located outside North America, present the certificates(s) and/ or document(s) that require a guarantee to a local financial institution that has a corresponding Canadian or American affiliate which is a member of an acceptable Medallion Signature Guarantee Program. The corresponding affiliate will arrange for the signature to be over-guaranteed.

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The undersigned hereby exercises the right of such holder to be issued, and hereby subscribes for, Common Shares that are issuable pursuant to the exercise of such Warrants on the terms specified in such Warrant Certificate and in the Warrant Indenture.

The undersigned holder of the Warrants evidenced by this Warrant Certificate hereby exercises the right to acquire              Common Shares of Acasti Pharma Inc. for an aggregate purchase price of US$        .

Exercise Price Payable:

(A) equals US$1.50 for each Common Share, subject to adjustment

(B) If the Registration Statement ceases to be effective under the U.S. Securities Act and no exemption from the registration requirements of the U.S. Securities Act is available such that the Warrantholder may receive freely tradable Common Shares upon exercise of Warrants, the Warrants may be exercised on a “cashless” basis in accordance with Section 3.4(a) of the Warrant Indenture and the number of Common Shares received will be calculated by the Corporation in accordance with Section 3.4(c) of the Warrant Indenture.

Capitalized terms used herein have the meaning ascribed to them in the Warrant Indenture.

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The undersigned hereby irrevocably directs that the said Common Shares be issued, registered and delivered as follows:

Please print full name in which certificates representing the Common Shares are to be issued. If any Common Shares are to be issued to a person or persons other than the registered holder, the registered holder must pay to the Warrant Agent all exigible transfer taxes or other government charges, if any, and the Form of Transfer must be duly executed.

Once completed and executed, this Exercise Form must be mailed or delivered to Computershare Trust Company of Canada, c/o Corporate Trust Services, 1500 University Street, Suite 700, Montréal, Quebec H3A 3S8.

It is understood that the Corporation and Computershare Trust Company of Canada may require evidence to verify the foregoing representation.

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