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                                                                     EXHIBIT 4.3

                          REGISTRATION RIGHTS AGREEMENT

                       ASPREVA PHARMACEUTICALS CORPORATION

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                                TABLE OF CONTENTS

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<S>                                                                                 <C>
1.  DEFINITIONS; REGISTRATION RIGHTS............................................     1
    1.1    Definitions..........................................................     1
    1.2    Demand Registration..................................................     3
    1.3    Corporation Registration.............................................     4
    1.4    Form S-3 Registration................................................     5
    1.5    Obligations of the Corporation.......................................     6
    1.6    Furnish Information..................................................     7
    1.7    Expenses of Demand, Corporation and S-3 Registration.................     8
    1.8    Delay of Registration................................................     8
    1.9    Indemnification......................................................     8
    1.10   Reports Under Securities Exchange Act of 1934........................    10
    1.11   Assignment of Registration Rights....................................    11
    1.12   Limitations on Subsequent Registration Rights........................    11
    1.13   Market-Standoff Agreement............................................    12

2.  MISCELLANEOUS...............................................................    12
    2.1    Entire Agreement.....................................................    12
    2.2    Recapitalizations, Etc...............................................    13
    2.3    Successors and Assigns...............................................    13
    2.4    Amendments and Waivers...............................................    13
    2.5    Notices..............................................................    13
    2.6    Severability.........................................................    13
    2.7    Delays or Omissions; Remedies Cumulative.............................    14
    2.8    Currency.............................................................    14
    2.9    Attorney's Fees......................................................    14
    2.10   Governing Law........................................................    14
    2.11   Counterparts and Fax Signatures......................................    14
    2.12   Titles and Subtitles.................................................    14
    2.13   Aggregation of Stock.................................................    15

SCHEDULE A - SCHEDULE OF INVESTORS
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                          REGISTRATION RIGHTS AGREEMENT

THIS AGREEMENT dated for reference March 5, 2004

AMONG:

            ASPREVA PHARMACEUTICALS CORPORATION, a corporation incorporated
            under the laws of Canada and having its head office at Suite 1201,
            4464 Markham Street, Victoria, B.C., Canada, V8Z 7X8, Facsimile No.
            250.744.2498 (the "Corporation")

AND:

            THE INVESTORS LISTED IN SCHEDULE A HERETO (each an "Investor" and
            together, the "Investors")

WHEREAS:

A.    The Corporation and the Investors have entered into an Investment
Agreement (the "INVESTMENT AGREEMENT") of even date herewith pursuant to which
the Corporation desires to sell to the Investors and the Investors desire to
purchase from the Corporation shares of the Corporation's Preferred shares,
Series A (the "Series A Preferred Shares").

B.    A condition to the Investors' obligations under the Investment Agreement
is that the Corporation and the Investors enter into this Agreement in order to
provide the Investors with certain rights to register Common Shares issuable
upon conversion of the Series A Preferred Shares held by the Investors.

C.    The Corporation desires to induce the Investors to purchase shares of
Series A Preferred Shares pursuant to the Investment Agreement by agreeing to
the terms and conditions set forth herein.

NOW THEREFORE THIS AGREEMENT WITNESSES that in consideration of, and in reliance
on, the premises, representations, warranties, covenants and agreements set
forth in this Agreement, the parties hereby agree as follows:

1.          DEFINITIONS; REGISTRATION RIGHTS

1.1         DEFINITIONS

For purposes of this Agreement:

      (a)   "BOARD" means the Board of Directors of the Corporation, as the same
            shall be constituted from time to time;

      (b)   "COMMON SHARES" means the voting common shares in the capital of the
            Corporation;

      (c)   "EXEMPT REGISTRATION" means a registration statement relating to the
            sale of securities by the Corporation pursuant to a stock option,
            stock purchase or similar benefit plan or an SEC Rule 145
            transaction or any other registration statement that would not
            customarily provide for the sale of secondary equity shares for
            cash;

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                                     - 2 -

      (d)   "FORM S-3" means such form or a registration statement or form F-3,
            if applicable, under the Securities Act as in effect on the date
            hereof or any successor forms under the Securities Act that are
            intended to be used as a short form for the registration of
            distributions of secondary equity shares;

      (e)   "HOLDER" means any Person owning or having the right to acquire
            Registrable Securities or any assignee thereof in accordance with
            Section 1.11 of this Agreement;

      (f)   "INITIATING HOLDERS" shall have the meaning ascribed thereto in
            Section 1.2(a) of this Agreement;

      (g)   "PERSON" or "PERSON" means any individual, corporation, partnership,
            limited liability Corporation, trust, business, association or
            government or political subdivision thereof, governmental agency or
            other entity;

      (h)   "QUALIFIED IPO" shall have the meaning ascribed thereto in the
            Series A Preferred Share terms contained in the articles of the
            Corporation;

      (i)   "PREFERRED SHARES" means the class of Preferred shares, issuable in
            series, in the capital of the Corporation, including, for greater
            certainty, the Series A Preferred Shares;

      (j)   "REGISTER," "REGISTERED," and "REGISTRATION" refer to a registration
            effected by preparing and filing a registration statement or similar
            document in compliance with the Securities Act and the declaration
            or ordering of effectiveness of such registration statement or
            document;

      (k)   "REGISTRABLE SECURITIES" means (i) the Common Shares issuable or
            issued upon conversion of the Series A Preferred Shares, and (ii)
            any other Common Shares of the Corporation issued as (or issuable
            upon the conversion or exercise of any warrant, right or other
            security which is issued as) a dividend or other distribution with
            respect to, or in exchange for or in replacement of, the shares
            determined to be Registrable Securities pursuant to clause (i) and
            this clause (ii); PROVIDED, HOWEVER, that the foregoing definition
            shall exclude in all cases any Registrable Securities sold by a
            Holder in a transaction in which its rights under this Agreement are
            not assigned. Notwithstanding the foregoing, securities shall only
            be treated as Registrable Securities if and so long as they have not
            been (A) sold to or through a broker or dealer or underwriter in a
            public distribution or a public securities transaction, or (B) sold
            in a transaction exempt from the registration and prospectus
            delivery requirements of the Securities Act under Section 4(1)
            thereof so that all transfer restrictions, and restrictive legends
            with respect thereto, if any, are removed upon the consummation of
            such sale;

      (l)   The number of "REGISTRABLE SECURITIES THEN OUTSTANDING" shall equal
            the number of Common Shares outstanding which are, and the number of
            Common Shares issuable pursuant to then exercisable or convertible
            securities which are, Registrable Securities;

      (m)   "SEC" means the Securities and Exchange Commission or any other
            federal agency at the time administering the Securities Act;

      (n)   "SECURITIES ACT" means the United States Securities Act of 1933;

      (o)   "SERIES A PREFERRED SHARES" has the meaning given to it in Recital A
            above; and

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                                     - 3 -

      (p)   The symbol "$" denotes United States currency.

1.2         DEMAND REGISTRATION

      (a)   INITIATION. If the Corporation shall receive at any time after 180
            days after the Corporation's Qualified IPO, a written request from
            the Holders of at least thirty-five percent (35%) of the Registrable
            Securities then outstanding (the "INITIATING HOLDERS") that the
            Corporation file a registration statement under the Securities Act
            with respect to at least twenty percent (20%) of the Registrable
            Securities, or any lesser percentage if the anticipated aggregate
            proceeds, net of underwriting discounts and expenses, would exceed
            $5,000,000, then the Corporation shall promptly (but in no event
            later than 10 days of the receipt thereof) give notice of such
            request to all other Holders and shall, subject to the limitations
            of Section 1.2(b), use its reasonable commercial efforts to effect
            as soon as practicable the registration under the Securities Act of
            all Registrable Securities which the Initiating Holders request to
            be registered, together with any Registrable Securities of any
            Holder joining in such request as are specified in a notice given by
            any such Holder to the Corporation within 20 days after receipt of
            the Corporation's notice.

      (b)   UNDERWRITTEN OFFERING. If the Initiating Holders intend to
            distribute the Registrable Securities covered by their request by
            means of an underwriting, they shall so advise the Corporation as a
            part of their request made pursuant to this Section 1.2 and the
            Corporation shall include such information in the written notice
            referred to in Section 1.2(a). The underwriter shall be selected by
            a majority in interest of the Initiating Holders and shall be
            reasonably acceptable to the Corporation. The right of any Holder to
            include its Registrable Securities in such registration shall be
            conditioned upon such Holder's participation in such underwriting.
            All Holders proposing to distribute Registrable Securities through
            such underwriting shall (together with the Corporation as provided
            in Section 1.5(e)) enter into an underwriting agreement in customary
            form with the underwriter or underwriters selected for such
            underwriting. Notwithstanding any other provision of this Section
            1.2, if the underwriter advises the Initiating Holders in writing
            that marketing factors require a limitation of the number of shares
            to be underwritten, then the Initiating Holders shall so advise all
            Holders of Registrable Securities which would otherwise be
            underwritten pursuant hereto, and the number of shares of
            Registrable Securities that may be included in the underwriting
            shall be allocated among all participating Holders, including the
            Initiating Holders, in proportion (rounded to the nearest 100
            shares) to the amount of Registrable Securities of the Corporation
            then owned by each Holder; PROVIDED, HOWEVER, that the number of
            Registrable Securities to be included in such underwriting shall not
            be reduced unless all other securities are first entirely excluded
            from the underwriting. For purposes of the preceding apportionment,
            for any participating Holder that is a partnership, limited
            liability Corporation or corporation, the partners, retired
            partners, members, retired members and shareholders of such Holder,
            or the estates and family members of any such partners, members,
            retired partners or retired members and any trusts for the benefit
            of any of the foregoing persons shall be deemed to be a single
            "selling shareholder," and any pro-rata reduction with respect to
            such "SELLING SHAREHOLDER" shall be based upon the aggregate amount
            of shares carrying registration rights owned by all Persons included
            in such "selling shareholder," as defined in this sentence.

      (c)   CORPORATION DEFERRAL. If the Corporation shall furnish to the
            Initiating Holders a certificate signed by the Chief Executive
            Officer of the Corporation stating that in the

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            good faith judgment of the Board, it would be seriously detrimental
            to the Corporation and its shareholders for such registration
            statement to be filed and it is therefore essential to defer the
            filing of such registration statement, the Corporation shall have
            the right to defer such filing for a period of not more than 30 days
            after receipt of the request of the Initiating Holders; PROVIDED,
            HOWEVER, that the Corporation may not utilize this right more than
            twice in any 12-month period.

      (d)   MAXIMUM NUMBER OF REGISTRATIONS. The Corporation shall not be
            obligated to effect, or to take any action to effect, any
            registration pursuant to this Section 1.2 after the Corporation has
            effected two registrations pursuant to this Section 1.2 and such
            registrations have been declared or ordered effective.

      (e)   LOCKOUT PERIOD. The Corporation shall not be obligated to effect, or
            to take any action to effect, any registration pursuant to this
            Section 1.2 during the period starting with the date 60 days prior
            to the Corporation's good faith estimate of the date of filing of,
            and ending on a date 180 days after the effective date of, a
            registration subject to Sections 1.2 or 1.3 hereof; provided that if
            said registration statement is not yet effective, the Corporation
            shall be actively employing in good faith all reasonable efforts to
            cause such registration statement to be filed and to become
            effective; provided, further, that in no event shall such aggregate
            period exceed 240 days.

      (f)   SIMULTANEOUS LISTING. The Corporation shall not cause its shares to
            be listed for trading on the Toronto Stock Exchange unless its
            shares are also then listed for trading on either The Nasdaq
            National Market or the New York Stock Exchange; provided that
            Holders of at least fifty-one percent (51%) of the Registrable
            Securities then outstanding may waive in writing this requirement.
            The Holders acknowledge that the Corporation does not intend to
            cause or permit its shares to be listed for trading on The Nasdaq
            National Market or the New York Stock Exchange unless its shares are
            also then listed for trading on the Toronto Stock Exchange.

1.3         CORPORATION REGISTRATION

      (a)   INITIATION. If (but without any obligation to do so) the Corporation
            proposes to register (including for this purpose a registration
            effected by the Corporation for shareholders other than the Holders)
            any of its stock in connection with the public offering of such
            securities solely for cash (other than an Exempt Registration), the
            Corporation shall, at such time, promptly give each Holder notice of
            such registration. Upon the written request of each Holder given
            within 20 days after receipt by such Holder of the Corporation's
            notice, the Corporation shall, subject to the provisions of Section
            1.3(b), use reasonable commercial efforts to cause to be registered
            all of the Registrable Securities that each such Holder has
            requested to be registered.

      (b)   UNDERWRITTEN OFFERING. In connection with any offering involving an
            underwriting of shares of the Corporation's capital stock, the
            Corporation shall not be required under Section 1.3(a) to include
            any of the Holders' securities in such underwriting unless they
            accept the terms of the underwriting as agreed upon between the
            Corporation and the underwriters selected by it (or by other persons
            entitled to select the underwriters), and then only in such quantity
            as the underwriters determine in their sole discretion will not
            jeopardize the success of the offering by the Corporation or would
            result in a substantial risk that the price per share will be
            reduced. If the total amount of securities, including Registrable
            Securities, requested by shareholders to be included in such
            offering exceeds

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                                     - 5 -

            the amount of securities sold other than by the Corporation that the
            underwriters determine in their sole discretion is compatible with
            the success of the offering or would result in a substantial risk
            that the price per share will be reduced, then the Corporation shall
            be required to include in the offering only that number of such
            securities, including Registrable Securities, which the underwriters
            determine in their sole discretion will not jeopardize the success
            of the offering (the securities so included to be apportioned first
            to the Corporation and then pro rata (to the nearest 100 shares)
            among the selling shareholders according to the total amount of
            securities entitled to be included therein owned by each selling
            shareholder or in such other proportions as shall mutually be agreed
            to by such selling shareholders). The number of Registrable
            Securities to be included in an underwriting under this Section 1.3
            shall not be reduced unless all other securities held by
            shareholders of the Corporation other than Registrable Securities
            are first entirely excluded from the underwriting. For purposes of
            the preceding apportionment, for any participating Holder that is a
            partnership, limited liability Corporation or corporation, the
            partners, retired partners, members, retired members and
            shareholders of such Holder, or the estates and family members of
            any such partners, members, retired partners or members and any
            trusts for the benefit of any of the foregoing persons shall be
            deemed to be a single "selling shareholder," and any pro-rata
            reduction with respect to such "SELLING SHAREHOLDER" shall be based
            upon the aggregate amount of shares carrying registration rights
            owned by all Persons included in such "selling shareholder," as
            defined in this sentence.

      (c)   RIGHT TO TERMINATE REGISTRATION. The Corporation shall have the
            right to terminate or withdraw any registration initiated by it
            under this Section 1.3 prior to the effectiveness of such
            registration whether or not any Holder has elected to include
            Registrable Securities in such registration.

1.4         FORM S-3 REGISTRATION

      (a)   INITIATION. If the Corporation shall receive from any Holder or
            Holders of not less than thirty five percent (35%) of the
            Registrable Securities then outstanding a written request or
            requests that the Corporation effect a registration on Form S-3 with
            respect to at least twenty percent (20%) of the Registrable
            Securities, the Corporation will promptly give written notice of the
            proposed registration to all other Holders and as soon as
            practicable, use reasonable commercial efforts to effect such
            registration of such Holder's or Holders' Registrable Securities as
            are specified in such request, together with all or such portion of
            the Registrable Securities of any other Holder or Holders joining in
            such request as are specified in a written request given within 20
            days after receipt of such notice from the Corporation.

      (b)   LIMITATIONS. Notwithstanding Section 1.4(a), the Corporation shall
            not be obligated to effect any such registration pursuant to this
            Section 1.4: (i) if Form S-3 is not available for such offering by
            the Holders; (ii) if the Holders, together with the holders of any
            other securities of the Corporation entitled for inclusion in such
            registration, propose to sell Registrable Securities and such other
            securities (if any) at an aggregate price to the public (net of any
            underwriters' discounts or commissions) of less than $2,000,000;
            (iii) if the Corporation shall furnish to the Holders a certificate
            signed by the Chief Executive Officer of the Corporation stating
            that in the good faith judgment of the Board, it would be seriously
            detrimental to the Corporation and its shareholders for such Form
            S-3 registration to be effected at such time, in which event the
            Corporation shall have the right to defer the filing of the Form S-3
            for a period of not more than 30 days after receipt

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                                     - 6 -

            of the request of the Holder or Holders under this Section 1.4;
            PROVIDED, HOWEVER, that the Corporation shall not utilize this right
            more than twice in any 12-month period; or (iv) if the Corporation
            has, within the twelve (12) month period preceding the date of such
            request, already effected two (2) registrations on Form S-3 for
            Holders pursuant to this Section 1.4.

      (c)   S-3'S NOT DEMANDS. Registrations effected pursuant to this Section
            1.4 shall not be counted as a demand for registration effected
            pursuant to Section 1.2.

      (d)   UNDERWRITTEN OFFERINGS. The substantive provisions of Section 1.2(b)
            shall apply to the registration if it relates to an underwritten
            offering.

1.5         OBLIGATIONS OF THE CORPORATION

Whenever required under this Section 1 to effect the registration of any
Registrable Securities, the Corporation shall, as expeditiously as reasonably
possible:

      (a)   Prepare and file with the SEC a registration statement with respect
            to such Registrable Securities and use its reasonable commercial
            efforts to cause such registration statement to become effective,
            and, in the instances of a registration initiated pursuant to
            Section 1.2 or 1.4, upon the request of the Holders of a majority of
            the Registrable Securities registered thereunder, keep such
            registration statement effective for up to one hundred twenty (120)
            days. The Corporation will not be required to file, cause to be
            effective or maintain the effectiveness of any registration
            statement that contemplates a distribution of securities on a
            delayed or continuous basis pursuant to Rule 415, or any successor
            rule, under the Securities Act.

      (b)   Prepare and file with the SEC such amendments and supplements to
            such registration statement and the prospectus used in connection
            with such registration statement as may be necessary to comply with
            the provisions of the Securities Act.

      (c)   Furnish to the Holders such numbers of copies of a prospectus,
            including a preliminary prospectus, in conformity with the
            requirements of the Securities Act, and such other documents as they
            may reasonably request in order to facilitate the disposition of
            such Registrable Securities.

      (d)   Use its reasonable commercial efforts to register and qualify the
            securities covered by such registration statement under such other
            securities or Blue Sky laws of such jurisdictions as shall be
            reasonably requested by the Holders, provided that the Corporation
            shall not be required in connection therewith or as a condition
            thereto to qualify to do business or to file a general consent to
            service of process in any such states or jurisdictions where the
            Corporation is not already subject to process.

      (e)   In the event of any underwritten public offering, enter into and
            perform its obligations under an underwriting agreement with the
            managing underwriter of such offering in usual and customary form
            and consistent with the other provisions of this Agreement. Each
            Holder participating in such underwriting shall also enter into and
            perform its obligations under such an agreement.

      (f)   Promptly notify each Holder of Registrable Securities covered by the
            registration statement at any time when the Corporation becomes
            aware of the happening of any

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            event as a result of which the registration statement or the
            prospectus included in such registration statement or any supplement
            to the prospectus (as then in effect) contains any untrue statement
            of a material fact or omits to state a material fact necessary to
            make the statements therein (in the case of the prospectus, in light
            of the circumstances under which they were made) not misleading or,
            if for any other reason it shall be necessary during such time
            period to amend or supplement the registration statement or the
            prospectus in order to comply with the Securities Act, whereupon, in
            either case, each Holder shall immediately cease to use such
            registration statement or prospectus for any purpose and, as
            promptly as practicable thereafter, the Corporation shall prepare
            and file with the SEC, and furnish without charge to the appropriate
            Holders and managing underwriters, if any, a supplement or amendment
            to such registration statement or prospectus which will correct such
            statement or omission or effect such compliance and such copies
            thereof as the Holders and any underwriters may reasonably request.

      (g)   Cause all such Registrable Securities registered pursuant hereunder
            to be listed on each securities exchange or over-the-counter market
            on which similar securities issued by the Corporation are then
            listed, if applicable.

      (h)   Provide a transfer agent and registrar for such Registrable
            Securities and a CUSIP number for all such Registrable Securities,
            in each case not later than the effective date of such registration.

      (i)   Use its reasonable commercial efforts to furnish, at the request of
            any Holder requesting registration of Registrable Securities
            pursuant to this Section 1.5, on the date that such Registrable
            Securities are delivered to the underwriters for sale in connection
            with a registration pursuant to this Section 1.5, if such securities
            are being sold through underwriters, or, if such securities are not
            being sold through underwriters, on the date that the registration
            statement with respect to such securities becomes effective, (i) an
            opinion, dated such date, of the counsel representing the
            Corporation for the purposes of such registration, in form and
            substance as is customarily given to underwriters in an underwritten
            public offering, addressed to the underwriters, if any, and to the
            Holders requesting registration of Registrable Securities, and (ii)
            a letter dated such date, from the independent certified public
            accountants of the Corporation, in form and substance as is
            customarily given by independent certified public accountants to
            underwriters in an underwritten public offering, addressed to the
            underwriters, if any, and to the Holders requesting registration of
            Registrable Securities (to the extent the then applicable standards
            of professional conduct permit said letter to be addressed to the
            Holders).

1.6         FURNISH INFORMATION

It shall be a condition precedent to the obligations of the Corporation to take
any action pursuant to this Section 1 with respect to the Registrable Securities
of any selling Holder that such Holder shall furnish to the Corporation such
information regarding itself, the Registrable Securities held by it, and the
intended method of disposition of such securities as shall be required to effect
the registration of such Holder's Registrable Securities. The Corporation shall
have no obligation with respect to any registration requested pursuant to
Section 1.2 or Section 1.4 of this Agreement if, as a result of the application
of the preceding sentence, the number of shares or the anticipated aggregate
offering price of the Registrable Securities to be included in the registration
does not equal or exceed the number of shares or the anticipated aggregate
offering price required to originally trigger the Corporation's obligation to
initiate such registration as specified in Section 1.2(a) or Section 1.4(b),
whichever is applicable; provided that

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the Corporation is acting in good faith and has provided reasonable notice and
opportunity for such information to be furnished.

1.7         EXPENSES OF DEMAND, CORPORATION AND S-3 REGISTRATION

All expenses other than underwriting discounts and commissions incurred in
connection with registrations initiated pursuant to (i) the registrations under
Section 1.2, (ii) the registrations under Section 1.3, and (iii) the
registrations under Section 1.4 (collectively, the "COVERED REGISTRATIONS"),
including all registration, filing and qualification fees, printers' and
accounting fees, fees and disbursements of counsel for the Corporation, and the
fees and disbursements of one counsel for the selling Holders selected by
Holders selling a majority of the subject Registrable Securities (the
"SHAREHOLDER LEGAL FEES"), shall be borne by the Corporation; PROVIDED, HOWEVER,
that the Corporation shall not be required to pay for any expenses of any
registration proceeding begun pursuant to Section 1.2 if the registration
request is subsequently withdrawn at the request of the Holders of a majority of
the Registrable Securities to be registered (in which case all participating
Holders shall bear such expenses on a pro rata basis), unless the Holders of a
majority of the Registrable Securities agree to forfeit their right to one
demand registration pursuant to Section 1.2. The Corporation shall be obligated
to reimburse the Holders for Shareholder Legal Fees in each Covered Registration
up to a maximum amount of $25,000. All expenses incurred in connection with
registrations other than Covered Registrations shall be borne among the selling
shareholders and, if it participates in such registration, the Corporation.

1.8         DELAY OF REGISTRATION

No Holder shall have any right to obtain or seek an injunction restraining or
otherwise delaying any registration as the result of any controversy that might
arise with respect to the interpretation or implementation of this Section 1.

1.9         INDEMNIFICATION

In the event any Registrable Securities are included in a registration statement
under this Section 1:

      (a)   INDEMNIFICATION BY THE CORPORATION. To the extent permitted by law,
            the Corporation will indemnify and hold harmless each Holder, any
            underwriter (as defined in the Securities Act) for such Holder and
            each person, if any, who controls such Holder or underwriter within
            the meaning of the Securities Act or the United States Securities
            Exchange Act of 1934, as amended (the "EXCHANGE ACT"), against any
            losses, claims, damages, or liabilities (joint or several) to which
            they may become subject under the Securities Act, the Exchange Act
            or other federal or state law, insofar as such losses, claims,
            damages, or liabilities (or actions in respect thereof) arise out of
            or are based upon any of the following statements, omissions or
            violations (collectively a "VIOLATION"): (i) any untrue statement or
            alleged untrue statement of a material fact contained in such
            registration statement, including any preliminary prospectus or
            final prospectus contained therein or any amendments or supplements
            thereto; (ii) the omission or alleged omission to state therein a
            material fact required to be stated therein, or necessary to make
            the statements therein not misleading; or (iii) any violation or
            alleged violation by the Corporation of the Securities Act, the
            Exchange Act, any state securities law or any rule or regulation
            promulgated under the Securities Act, the Exchange Act or any state
            securities law; and the Corporation will pay to each such Holder,
            underwriter or controlling person, as incurred, any legal or other
            expenses reasonably incurred by them in connection with
            investigating or defending any such loss, claim, damage, liability,
            or action; provided, however, that the indemnity agreement contained
            in this Section 1.9(a)

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                                     - 9 -

            shall not apply to amounts paid in settlement of any such loss,
            claim, damage, liability, or action if such settlement is effected
            without the consent of the Corporation (which consent shall not be
            unreasonably withheld), nor shall the Corporation be liable to any
            Holder, underwriter or controlling person for any such loss, claim,
            damage, liability, or action to the extent that it arises out of or
            is based upon a Violation which occurs in reliance upon and in
            conformity with written information furnished expressly for use in
            connection with such registration by the Holder, underwriter or
            controlling person seeking indemnification hereunder or failure of
            the Holder to deliver a prospectus after sufficient quantities have
            been provided by the Corporation.

      (b)   INDEMNIFICATION BY THE HOLDERS. To the extent permitted by law, each
            selling Holder will indemnify and hold harmless the Corporation,
            each of its directors, each of its officers who has signed the
            registration statement, each Person, if any, who controls the
            Corporation within the meaning of the Securities Act, any
            underwriter, any other Holder selling securities in such
            registration statement and any controlling person of any such
            underwriter or other Holder, against any losses, claims, damages, or
            liabilities (joint or several) to which any of the foregoing persons
            may become subject, under the Securities Act, the Exchange Act or
            other federal or state law, insofar as such losses, claims, damages,
            or liabilities (or actions in respect thereto) arise out of or are
            based upon any Violation, in each case to the extent (and only to
            the extent) that such Violation occurs in reliance upon and in
            conformity with written information furnished by such Holder
            expressly for use in connection with such registration; and each
            such Holder will pay, as incurred, any legal or other expenses
            reasonably incurred by any person intended to be indemnified
            pursuant to this Section 1.9(b), in connection with investigating or
            defending any such loss, claim, damage, liability, or action;
            PROVIDED, HOWEVER, that the indemnity agreement contained in this
            Section 1.9(b) shall not apply to amounts paid in settlement of any
            such loss, claim, damage, liability or action if such settlement is
            effected without the consent of the Holder, which consent shall not
            be unreasonably withheld; PROVIDED, HOWEVER, that in no event shall
            any indemnity under this Section 1.9(b) exceed the net proceeds from
            the offering received by such Holder.

      (c)   PROCEDURES. Promptly after receipt by an indemnified party under
            this Section 1.9 of notice of the commencement of any action
            (including any governmental action), such indemnified party will, if
            a claim in respect thereof is to be made against any indemnifying
            party under this Section 1.9, deliver to the indemnifying party a
            written notice of the commencement thereof and the indemnifying
            party shall have the right to participate in, and, to the extent the
            indemnifying party so desires, jointly with any other indemnifying
            party similarly noticed, to assume the defense thereof with counsel
            mutually satisfactory to the parties; PROVIDED, HOWEVER, that an
            indemnified party (together with all other indemnified parties which
            may be represented without conflict by one counsel) shall have the
            right to retain one separate counsel, with the reasonable fees and
            expenses to be paid by the indemnifying party, if representation of
            such indemnified party by the counsel retained by the indemnifying
            party would be inappropriate due to actual or potential differing
            interests between such indemnified party and any other party
            represented by such counsel in such proceeding. The failure to
            deliver written notice to the indemnifying party within a reasonable
            time of the commencement of any such action, if materially
            prejudicial to its ability to defend such action, shall relieve such
            indemnifying party of any liability to the indemnified party under
            this Section 1.9, but the omission so to deliver written notice to
            the indemnifying party will not relieve it of any liability that it
            may have to any indemnified party otherwise than under this Section
            1.9. No indemnifying party, in the defense of any such claim or
            litigation, shall, except with

<PAGE>
                                     - 10 -

            the consent of each indemnified party, consent to entry of any
            judgment or enter into any settlement which does not include as an
            unconditional term thereof the giving by the claimant or plaintiff
            to such indemnified party of a release from all liability in respect
            to such claim or litigation. The indemnity agreements contained in
            this Section 1.9 shall not apply to amounts paid in settlement of
            any loss, claim, damage, liability or action if such settlement is
            effected without the consent of the indemnifying party, which shall
            not be unreasonably withheld.

      (d)   CONTRIBUTION. If the indemnification provided for in this Section
            1.9 is held by a court of competent jurisdiction to be unavailable
            to an indemnified party with respect to any loss, liability, claim,
            damage or expense referred to therein, then the indemnifying party,
            in lieu of indemnifying such indemnified party hereunder, shall
            contribute to the amount paid or payable by such indemnified party
            as a result of such loss, liability, claim, damage, or expense in
            such proportion as is appropriate to reflect the relative fault of
            the indemnifying party on the one hand and of the indemnified party
            on the other in connection with the statements or omissions that
            resulted in such loss, liability, claim, damage or expense as well
            as any other relevant equitable considerations; provided, that in no
            event shall any contribution by a Holder under this Section 1.9(d)
            exceed the net proceeds from the offering received by such Holder.
            The relative fault of the indemnifying party and of the indemnified
            party shall be determined by reference to, among other things,
            whether the untrue or alleged untrue statement of a material fact or
            the omission to state a material fact relates to information
            supplied by the indemnifying party or by the indemnified party and
            the parties' relative intent, knowledge, access to information, and
            opportunity to correct or prevent such statement or omission.

      (e)   UNDERWRITING AGREEMENT. Notwithstanding the foregoing, to the extent
            that the provisions on indemnification and contribution contained in
            the underwriting agreement entered into in connection with the
            underwritten public offering are in conflict with the foregoing
            provisions, the provisions in the underwriting agreement shall
            control.

      (f)   SURVIVAL. The obligations of the Corporation and Holders under this
            Section 1.9 shall survive the completion of any offering of
            Registrable Securities in a registration statement under this
            Section 1.

1.10        REPORTS UNDER SECURITIES EXCHANGE ACT OF 1934

With a view to making available to the Holders the benefits of Rule 144
promulgated under the Securities Act and any other rule or regulation of the SEC
that may at any time permit a Holder to sell securities of the Corporation to
the public without registration or pursuant to a registration on Form S-3, the
Corporation agrees to:

      (a)   make and keep public information available, as those terms are
            understood and defined in SEC Rule 144, at all times after the
            effective date of the first registration statement filed by the
            Corporation for the offering of its securities to the general public
            so long as the Corporation remains subject to the periodic reporting
            requirements under Sections 13 or 15(d) of the Exchange Act;

      (b)   file with the SEC in a timely manner all reports and other documents
            as may be required of the Corporation under the Securities Act and
            the Exchange Act; and

<PAGE>
                                     - 11 -

      (c)   furnish to any Holder, so long as the Holder owns any Registrable
            Securities, forthwith upon request: (i) a written statement by the
            Corporation that it has complied with the reporting requirements of
            SEC Rule 144, the Securities Act and the Exchange Act (at any time
            after it has become subject to such reporting requirements), or that
            it qualifies as a registrant whose securities may be resold pursuant
            to Form S-3 (at any time after it so qualifies); (ii) a copy of the
            most recent annual or quarterly report of the Corporation and such
            other reports and documents so filed by the Corporation; and (iii)
            such other information as may be reasonably requested in availing
            any Holder of any rule or regulation of the SEC which permits the
            selling of any such securities without registration or pursuant to
            such form.

1.11        ASSIGNMENT OF REGISTRATION RIGHTS

The rights to cause the Corporation to register securities granted Holders under
Sections 1.2, 1.3 and 1.4 may be assigned to a transferee or assignee in
connection with any transfer or assignment of Registrable Securities by a
Holder; provided that:

      (a)   such transfer may otherwise be effected in accordance with
            applicable securities laws and restrictions on transfer agreed upon
            by the Holder and the Corporation (including those set forth in the
            Investment Agreement);

      (b)   notice of such assignment is given to the Corporation;

      (c)   such transferee or assignee is:

            (1)   an affiliate or constituent partner, retired partner, member,
                  retired member or shareholder of such Holder or of the parent
                  entity of such Holder, or

            (2)   a spouse, ancestor or descendant of such Holder or

            (3)   a trust for the benefit of such Holder or any spouse, ancestor
                  or descendant of such Holder, or

            (4)   not a direct competitor of the Corporation, as determined in
                  good faith by the Corporation's Board of Directors, and such
                  transferee or assignee acquires from such Holder at least 20%
                  of all of the Registrable Securities then held by such
                  transferring Holder; and

      (d)   such transferee or assignee agrees to be bound by all provisions of
            this Agreement.

1.12        LIMITATIONS ON SUBSEQUENT REGISTRATION RIGHTS

From and after the date of this Agreement, the Corporation shall not, without
the prior written consent of the Holders of at least sixty percent (60%) of the
outstanding Registrable Securities, enter into any agreement with any holder or
prospective holder of any securities of the Corporation which would allow such
holder or prospective holder:

      (a)   to include such securities in any registration filed under Section
            1.2 hereof, unless under the terms of such agreement, such holder or
            prospective holder may include such securities in any such
            registration only to the extent that the inclusion of his securities
            will not reduce the amount of the Registrable Securities of the
            Holders which is included;

<PAGE>
                                     - 12 -

      (b)   to make a demand registration which could result in such
            registration statement being declared effective prior to the earlier
            of either of the dates set forth in Section 1.2(a) or within 120
            days after the effective date of any registration effected pursuant
            to Section 1.2 or

      (c)   to have or to exercise registration rights equivalent or superior to
            any of the rights granted to the Holders hereunder.

1.13        MARKET-STANDOFF AGREEMENT

      (a)   MARKET-STANDOFF AGREEMENT. In connection with the Qualified IPO of
            the Corporation's securities, each Holder hereby agrees not to sell,
            make any short sale of, loan, grant any option for the purchase of,
            or otherwise dispose of any securities of the Corporation (other
            than any disposed of in the registration and those acquired by the
            Holder in the registration or thereafter in open market
            transactions) without the prior written consent of the Corporation
            or such underwriters, as the case may be, for such period of time
            (not to exceed 180 days) from the effective date of such
            registration as may be requested by the Corporation or such managing
            underwriters and to execute an agreement reflecting the foregoing as
            may be requested by the underwriters at the time of the
            Corporation's Qualified IPO.

      (b)   LIMITATIONS. The obligations described in Section 1.13(a) shall
            apply only if all officers, directors and employees of the
            Corporation and all two-percent (2%) or greater securityholders
            enter into similar agreements. From and after the date of this
            Agreement, the Corporation shall use its reasonable commercial
            efforts to ensure that all holders of capital stock of the
            Corporation agree to be bound by terms substantially similar to
            those set forth in this Section 1.13.

      (c)   STOP-TRANSFER INSTRUCTIONS. In order to enforce the foregoing
            covenants, the Corporation may impose stop-transfer instructions
            with respect to the securities of each Holder (and the securities of
            every other person subject to the restrictions in Section 1.13(a)).

      (d)   TRANSFEREES BOUND. Each Holder agrees that prior to the
            Corporation's initial public offering it will not transfer
            securities of the Corporation unless each transferee agrees in
            writing to be bound by all of the provisions of this Section 1.13,
            provided that this Section 1.13(d) shall not apply to transfers
            pursuant to a registration statement or transfers after the
            six-month anniversary of the effective date of the Corporation's
            registration statement pursuant to its initial public offering.

2.          MISCELLANEOUS

2.1         ENTIRE AGREEMENT

This Agreement constitutes the entire agreement among the parties hereto
pertaining to the subject matter hereof, and any and all other written or oral
agreements relating to the subject matter hereof existing among any of the
parties hereto are expressly cancelled.

<PAGE>
                                     - 13 -

2.2         RECAPITALIZATIONS, ETC.

The provisions of this Agreement (including any calculation of share ownership)
shall apply, to the full extent set forth herein with respect to the Registrable
Securities and to the Common Shares, to any and all shares of capital stock of
the Corporation or any capital shares, partnership or member units or any other
security evidencing ownership interests in any successor or assign of the
Corporation (whether by merger, consolidation, sale of assets or otherwise) that
may be issued in respect of, in exchange for, or in substitution of any Common
Shares by reason of any stock dividend, split, combination, recapitalization,
liquidation, reclassification, merger, consolidation or otherwise.

2.3         SUCCESSORS AND ASSIGNS

Except as otherwise provided in this Agreement, and subject to the restriction
on transfer set forth in the Investment Agreement, the terms and conditions of
this Agreement shall inure to the benefit of and be binding upon the respective
permitted successors and assigns of the parties (including transferees of any of
the Series A Preferred Shares or any Common Shares issued upon conversion
thereof). Nothing in this Agreement, express or implied, is intended to confer
upon any party other than the parties hereto or their respective successors and
assigns any rights, remedies, obligations, or liabilities under or by reason of
this Agreement, except as expressly provided in this Agreement.

2.4         AMENDMENTS AND WAIVERS

Any term of this Agreement may be amended or waived only with the written
consent of the Corporation and the holders of at least sixty percent (60%) of
the of the Registrable Securities then outstanding. The Investors and their
successors and assigns acknowledge that by operation of this Section 2.4, the
holders of at least sixty percent (60%) of the then outstanding Registrable
Securities, when acting together with the Corporation, will have the right and
power to diminish or eliminate any rights or increase any or all obligations
under this Agreement.

2.5         NOTICES

Unless otherwise provided, any notice required or permitted by this Agreement
shall be in writing and shall be deemed sufficient upon delivery, when delivered
personally or by overnight courier or sent by telegram or confirmed fax, or if
mailed to a domestic address, 72 hours after being deposited in the U.S. or
Canadian mail, as certified or registered mail, with postage prepaid, and
addressed to the party to be notified at such party's address or fax number as
set forth below or on Exhibit A hereto or as subsequently modified by written
notice in accordance with this Section 2.5.

2.6         SEVERABILITY

If one or more provisions of this Agreement are held to be unenforceable under
applicable law, the parties agree to renegotiate such provision in good faith.
In the event that the parties cannot reach a mutually agreeable and enforceable
replacement for such provision, then:

      (a)   such provision shall be excluded from this Agreement;

      (b)   the balance of the Agreement shall be interpreted as if such
            provision were so excluded; and

      (c)   the balance of the Agreement shall be enforceable in accordance with
            its terms.

<PAGE>
                                     - 14 -

2.7         DELAYS OR OMISSIONS; REMEDIES CUMULATIVE

No delay or omission to exercise any right, power or remedy accruing to any
party under this Agreement, upon any breach or default of any other party under
this Agreement, shall impair any such right, power or remedy of such
non-breaching or non-defaulting party nor shall it be construed to be a waiver
of any such breach or default, or an acquiescence therein, or of or in any
similar breach or default thereafter occurring; nor shall any waiver of any
single breach or default be deemed a waiver of any other breach or default
theretofore or thereafter occurring. Any waiver, permit, consent or approval of
any kind or character on the part of any party of any breach or default under
this Agreement, or any waiver on the part of any party of any provisions or
conditions of this Agreement, must be in writing and shall be effective only to
the extent specifically set forth in such writing. All remedies, either under
this Agreement or by law or otherwise afforded to any party, shall be cumulative
and not alternative.

2.8         CURRENCY

All references in this Agreement to dollar amounts refer to the lawful currency
of the United States of America.

2.9         ATTORNEY'S FEES

If any action at law or in equity (including arbitration) is necessary to
enforce or interpret the terms of this Agreement, the prevailing party shall be
entitled to reasonable attorney's fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

2.10        GOVERNING LAW

This Agreement and all acts and transactions pursuant hereto shall be governed,
construed and interpreted in accordance with the laws of the Province of British
Columbia and the laws of Canada applicable therein, without giving effect to
principles of conflicts of laws.

2.11        COUNTERPARTS AND FAX SIGNATURES

This Agreement may be executed in two or more counterparts and by facsimile
signature, each of which shall be deemed an original, but all of which together
shall constitute one and the same instrument.

2.12        TITLES AND SUBTITLES

The titles and subtitles used in this Agreement are used for convenience only
and are not to be considered in construing or interpreting this Agreement.

<PAGE>
                                     - 15 -

2.13        AGGREGATION OF STOCK

All shares of the Corporation or acquired by affiliated persons (including
former and current partners, former and current members and former and current
shareholders) shall be aggregated together for the purpose of determining the
availability of any rights under this Agreement.

IN WITNESS WHEREOF the parties have executed this Agreement as of the date first
above written.

ASPREVA PHARMACEUTICALS CORPORATION

By:    /s/ RICHARD M. GLICKMAN
       -----------------------------------
Name:  Richard M. Glickman
Title: Chief Executive Officer

ASPREVA INVESTORS FUNDING SRL

By:    /s/ RONALD HUNT
       ------------------------------------
Name:  Ronald Hunt, its President

HBM BIOVENTURES (CAYMAN) LTD.

By:    /s/ JOHN ARNOLD
       -----------------------------------
Name:  John Arnold
Title: Chairman & Managing Director

<PAGE>

                                   SCHEDULE A

                              SCHEDULE OF INVESTORS

<TABLE>
<CAPTION>
          INVESTOR                              RECORD HOLDER                        NUMBER OF SHARES
-----------------------------------------------------------------------------------------------------
<S>                                     <C>                                          <C>
Aspreva Investors Funding SRL           Aspreva Investors Funding SRL                    8,755,483
-----------------------------------------------------------------------------------------------------
       HBM BioVentures                         HBM BioVentures                           1,117,721
        (Cayman) Ltd.                           (Cayman) Ltd.
</TABLE>