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                                                                   EXHIBIT 10.17



                                   SCHEDULE B

                       ASPREVA PHARMACEUTICALS CORPORATION

                                                        As of 7th December, 2004
Steven Piazza,
831 Kenmore Drive,
West Chester, PA 19380
USA

Dear Steve:

                         RE: CHANGE IN CONTROL AGREEMENT

      Aspreva Pharmaceuticals Corporation (the "CORPORATION") considers it
essential to the best interests of its members to foster the continuous
employment of its senior executive officers. In this regard, the Board of
Directors of the Corporation (the "BOARD") has determined that it is in the best
interests of the Corporation and its members that appropriate steps should be
taken to reinforce and encourage management's continued attention, dedication
and availability to the Corporation in the event of a Potential Change in
Control (as defined in Section 2), without being distracted by the uncertainties
which can arise from any possible changes in control of the Corporation.

      In order to induce you to agree to remain in the employ of the
Corporation, such agreement evidenced by the employment agreement entered into
as of the date of this Agreement between you and the Corporation (the
"EMPLOYMENT AGREEMENT") and in consideration of your agreement as set forth in
Section 3 below, the Corporation agrees that you shall receive and you agree to
accept the severance and other benefits set forth in this Agreement should your
employment with the Corporation be terminated subsequent to a Change in Control
(as defined in Section 2) in full satisfaction of any and all claims that now
exist or then may exist for remuneration, fees, salary, bonuses or severance
arising out of or in connection with your employment by the Corporation or the
termination of your employment:

1.    TERM OF AGREEMENT.

      This Agreement shall be in effect for a term commencing on the Effective
Date of the Employment Agreement (as therein defined) and ending on the date of
termination of the Employment Agreement.

2.    DEFINITIONS.


      (a)   "Affiliate" means a corporation that is an affiliate of the
            Corporation under the Securities Act (British Columbia), as amended
            from time to time.

      (b)   "Change in Control" of the Corporation shall be deemed to have
            occurred:

            (i)   if a merger, amalgamation, arrangement, consolidation,
                  reorganization or transfer takes place in which Equity
                  Securities of the Corporation possessing more than 50% of the
                  total combined voting power of the


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                  Corporation's outstanding Equity Securities are acquired by a
                  person or persons different from the persons holding those
                  Equity Securities immediately prior to such transaction, and
                  the composition of the Board following such transaction is
                  such that the directors of the Corporation prior to the
                  transaction constitute less than 50% of the Board membership
                  following the transaction, except that no Change in Control
                  will be deemed to occur if such merger, amalgamation,
                  arrangement, consolidation, reorganization or transfer is with
                  any subsidiary or subsidiaries of the Corporation;

            (ii)  if any person, or any combination of persons (different from
                  those person(s) holding Equity Securities prior to the date
                  hereof) acting jointly or in concert by virtue of an
                  agreement, arrangement, commitment or understanding shall
                  acquire or hold, directly or indirectly, 50% or more of the
                  voting rights attached to all outstanding Equity Securities;
                  or

            (iii) if any person, or any combination of persons (different from
                  those person(s) holding Equity Securities prior to the date
                  hereof) acting jointly or in concert by virtue of an
                  agreement, arrangement, commitment or understanding shall
                  acquire or hold, directly or indirectly, the right to appoint
                  a majority of the directors of the Corporation; or

            (iv)  if the Corporation sells, transfers or otherwise disposes of
                  all or substantially all of its assets, except that no Change
                  of Control will be deemed to occur if such sale or disposition
                  is made to a subsidiary or subsidiaries of the Corporation.

            provided however, that a Change in Control shall not be deemed to
            have occurred if such Change in Control results solely from the
            issuance of Equity Securities in connection with a bona fide
            financing or series of financings by the Corporation.

      (c)   "Base Salary" shall mean the annual base salary, as referred to in
            Section 3 (Base Salary), and as adjusted from time to time in
            accordance with Section 5 (Annual Review), of the Employment
            Agreement.

      (d)   "Bonus" shall mean the bonus referred to in Section 6 (Performance
            Bonus) of the Employment Agreement.

      (e)   "Cause" shall have the meaning set out in Section 19 (Termination
            by the Corporation for Cause) of the Employment Agreement.

      (f)   "Date of Termination" shall mean, if your employment is terminated,
            the date specified in the Notice of Termination.

      (g)   "Equity Security" in respect of a security of the Corporation, shall
            have the meaning ascribed thereto in Part II of the Securities Act
            (British Columbia), as it existed on the date of this Agreement, and
            also means any security carrying the


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            right to convert such security into, exchange such security for, or
            entitling the holder to subscribe for, any equity security, or into
            or for any such convertible or exchangeable security or security
            carrying a subscription right.

      (h)   "Good Reason" shall mean the occurrence of one or more of the
            following events, without your express written consent, within 12
            months of Change in Control:

            (i)   a material change in your status, position, authority or
                  responsibilities that does not represent a promotion from or
                  represents an adverse change from your status, position,
                  authority or responsibilities in effect immediately prior to
                  the Change in Control;

            (ii)  a material reduction by the Corporation, in the aggregate, in
                  your Base Salary, or incentive, retirement, health benefits,
                  bonus or other compensation plans provided to you immediately
                  prior to the Change in Control, unless an equitable
                  arrangement has been made with respect to such benefits in
                  connection with a Change in Control;

            (iii) a failure by the Corporation to continue in effect any other
                  compensation plan in which you participated immediately prior
                  to the Change in Control (except for reasons of
                  non-insurability), including but not limited to, incentive,
                  retirement and health benefits, unless an equitable
                  arrangement has been made with respect to such benefits in
                  connection with a Change in Control;

            (iv)  any request by the Corporation or any affiliate of the
                  Corporation that you participate in an unlawful act; or

            (v)   any purported termination of your employment by the
                  Corporation after a Change in Control which is not effected
                  pursuant to a Notice of Termination satisfying the
                  requirements of clause (i) below and for the purposes of this
                  Agreement, no such purported termination shall be effective.

      (i)   "Notice of Termination" shall mean a notice, in writing,
            communicated to the other party in accordance with Section 6 below,
            which shall indicate the specific termination provision in this
            Agreement relied upon and shall set forth in reasonable detail the
            facts and circumstances claimed to provide a basis for termination
            of your employment under the provision so indicated.

      (j)   "Potential Change in Control" of the Corporation shall be deemed to
            have occurred if:

            (i)   the Corporation enters into an agreement, the consummation of
                  which would result in the occurrence of a Change in Control;

            (ii)  any person (including the Corporation) publicly announces an
                  intention to take or to consider taking actions which if
                  consummated would constitute a Change in Control; or

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            (iii) the Board adopts a resolution to the effect that, for the
                  purposes of this Agreement, a Potential Change in Control of
                  the Corporation has occurred.

3.    POTENTIAL CHANGE IN CONTROL.

      You agree that, in the event of a Potential Change in Control of the
Corporation occurring after the Effective Date, and until 12 months after a
Change in Control, subject to your right to terminate your employment by issuing
and delivering a Notice of Termination for Good Reason, you will continue to
diligently carry out your duties and obligations, on the terms set out in the
Employment Agreement.

4.    COMPENSATION UPON TERMINATION FOLLOWING CHANGE IN CONTROL.

      Subject to compliance by you with Section 3, upon your employment
terminating pursuant to a Notice of Termination within 12 months after a Change
in Control, the Corporation agrees that you shall receive and you agree to
accept, the following payments in full satisfaction of any and all claims you
may have or then may have against the Corporation, for remuneration, fees,
salary, benefits, bonuses or severance, arising out of or in connection with
your employment by the Corporation or the termination of your employment:

      (a)   If your employment shall be terminated by the Corporation for Cause
            or by you other than for Good Reason, the terms of the Employment
            Agreement shall govern and the Corporation shall have no further
            obligations to you under this Agreement.

      (b)   If your employment by the Corporation shall be terminated by you for
            Good Reason or by the Corporation other than for Cause, then you
            shall be entitled to the payments and benefits provided below:

            (i)   subject to the withholding of all applicable statutory
                  deductions, the Corporation shall pay you a lump sum equal to
                  12 months' Base Salary, as referred to in Section 3 (Base
                  Salary) and as adjusted from time to time in accordance with
                  Section 5 (Annual Review) of the Employment Agreement, plus
                  other sums owed for arrears of salary, vacation pay and, if
                  awarded, Bonus;

            (ii)  to the extent permitted by law and subject to the terms and
                  conditions of any benefit plans in effect from time to time,
                  the Corporation shall maintain the benefits and payments set
                  out in Section 7 (Benefits) of the Employment Agreement during
                  the 12 month period;

            (iii) the Corporation shall arrange for you to be provided with such
                  outplacement career counselling services as are reasonable and
                  appropriate, to assist you in seeking new executive level
                  employment; and

            (iv)  all incentive stock options and trust shares granted to you by
                  the Corporation under any stock option and/or trust share
                  agreement that is


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                  entered into between you and the Corporation and is
                  outstanding at the time of termination of your employment,
                  which incentive stock options and or trust shares have not yet
                  vested, shall immediately vest upon the termination of your
                  employment and shall be fully exercisable by you in accordance
                  with the terms of the agreement or agreements under which such
                  options were granted.

You shall not be required to mitigate the amount of any payment provided for in
this Section 4 by seeking other employment or otherwise, nor will any sums
actually received be deducted.

5.    BINDING AGREEMENT.

      This Agreement shall enure to the benefit of and be enforceable by your
personal or legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees. If you die while any amount would still be
payable to you under this Agreement if you had continued to live, that amount
shall be paid in accordance with the terms of this Agreement to your devisee,
legatee or other designee or, if there is no such designee, to your estate.

6.    NOTICES.

      All notices and other communications that are required or permitted by
this Agreement must be in writing and shall be hand delivered or sent by express
delivery service or certified or registered mail, postage prepaid, or by
facsimile transmission (with written confirmation copy by registered mail) to
the parties at the addresses indicated below.

                  IF TO ASPREVA:

                  Aspreva Pharmaceuticals Corporation
                  Farris, Vaughan, Wills & Murphy
                  26th Floor, 700 West Georgia Street
                  Vancouver, BC  V7Y 1B3

                  Attn:  R. Hector MacKay-Dunn


                  IF TO STEVEN PIAZZA:

                  ATTN HENRY A. GLADSTONE

                  AND
                  Steven Piazza,
                  831 Kenmore Drive,
                  West Chester, PA 19380
                  USA

Any such notice shall be deemed to have been received on the earlier of the date
actually received or the date five (5) days after the same was posted or sent.
Either party may change its address or its facsimile number by giving the other
party written notice, delivered in accordance with this Section.

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7.    MODIFICATION: AMENDMENTS: ENTIRE AGREEMENT.

      This Agreement may not be modified, waived or discharged unless such
waiver, modification or discharge is agreed to in writing and signed by you and
such officer as may be specifically designated by the Board. No waiver by either
party at any time of any breach by the other party of, or compliance with, any
condition or provision of this Agreement to be performed by such other party
will be deemed a waiver of similar or dissimilar provisions or conditions at the
same or at any prior or subsequent time. Except as set forth in your Employment
Agreement, no agreements or representations, oral or otherwise, express or
implied, with respect to the subject matter hereof have been made by either
party which are not expressly set forth in this Agreement.

8.    GOVERNING LAW.

      This Agreement shall be governed by and interpreted in accordance with the
laws of the Province of British Columbia and applicable laws of Canada and the
parties hereto attorn to the exclusive jurisdiction of the provincial and
federal courts of such province.

9.    VALIDITY.

      The invalidity or unenforceability of any provision of this Agreement
shall not affect the validity or enforceability of any other provision of this
Agreement, which shall remain in full force and effect.

10.   NO EMPLOYMENT OR SERVICE CONTRACT

      Nothing in this Agreement shall confer upon you any right to continue in
the employment of the Corporation for any period of specific duration or
interfere with or otherwise restrict in any way the rights of the Corporation or
you, which rights are hereby expressly reserved by each, to terminate your
employment at any time for any reason whatsoever, with or without cause.

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      If the foregoing sets forth our agreement on this matter, kindly sign and
return to the Corporation a copy of this letter.

                                                  Yours truly,

                                                  ASPREVA PHARMACEUTICALS
                                                  CORPORATION


                                                  By:  /s/ NOEL HALL
                                                       -------------------------
                                                       Authorized Signatory

Accepted and agreed to by Steven Piazza as of the 7th day of December, 2004


/s/ STEVEN PIAZZA
------------------------------------------
STEVEN PIAZZA