THE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT
OF 1933, AS AMENDED (THE "SECURITIES ACT") OR ANY STATE SECURITIES LAW, AND MAY
NOT BE SOLD, TRANSFERRED, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE
ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT PURSUANT TO THE SECURITIES ACT OR
AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE CORPORATION THAT SUCH
REGISTRATION IS NOT REQUIRED.

UNLESS PERMITTED UNDER SECURITIES LEGISLATION, THE HOLDER OF THIS SECURITY MUST
NOT TRADE THIS SECURITY BEFORE MARCH 4, 2005.

                                  SCHEDULE "A"
                     FORM OF COMMON SHARE PURCHASE WARRANTS

                         COMMON SHARE PURCHASE WARRANTS

                        THE WARRANTS REPRESENTED BY THIS
                 CERTIFICATE WILL BE VOID AND OF NO VALUE UNLESS
                          EXERCISED ON OR BEFORE _, 20_

                              VIVENTIA BIOTECH INC.
                      (Continued under the laws of Ontario)

This is to certify that, for value received, Leslie L. Dan is the registered
holder ("HOLDER") of________________ common share purchase warrants ("WARRANTS")
each entitling the Holder to subscribe for and purchase one (1) fully paid and
non-assessable common share (a "COMMON SHARE") of Viventia Biotech Inc. (the
"CORPORATION"), on the terms set out below.

1.    EXERCISE

The Warrants may be exercised on or before 5:00 p.m. (Toronto time) on [THE DATE
WHICH IS FOUR YEARS FROM DATE OF ISSUANCE] (the "EXPIRY DATE") by the Holder by
completing the subscription form attached hereto and made a part hereof and
delivering same to the Corporate Secretary of the Corporation, at its principal
office at 10 Four Seasons Place, Suite 501, Toronto ON M9B 6H7, together with
this certificate and the appropriate sum being an amount equal to the Exercise
Price (as defined hereafter) multiplied by the number of Warrants for which
subscription is being made in the subscription form. The Corporation shall
notify each Holder in writing of any change of address of its principal office.

2.    EXERCISE PRICE

The exercise price shall be $2.00 per Warrant (the "EXERCISE PRICE") payable in
lawful money of Canada, subject to adjustment as provided herein.

3.    PAYMENT

The Common Shares subscribed for must be paid in full at the time of
subscription by certified cheque or bank draft payable in Canadian funds to or
to the order of the Corporation.


                                      (ii)

4.    SHARE CERTIFICATES

Upon compliance with the conditions as aforesaid, and subject to the provisions
under "Dilution" below, the Corporation will cause to be issued to the person or
persons in whose name or names the Common Shares so subscribed for are to be
issued, the number of Common Shares subscribed for and such person or persons
shall be deemed upon presentation and payment as aforesaid, to be the holder or
holders of record of such Common Shares. Within five (5) business days of
compliance of the conditions aforesaid, the Corporation will cause to be mailed
or delivered to the holder at the address or addresses specified in the attached
subscription form, a certificate or certificates evidencing the number of Common
Shares subscribed for. The certificate evidencing the Common Shares subscribed
for shall contain the following legend:

                  "THE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE UNITED
                  STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
                  ACT") OR ANY STATE SECURITIES LAW, AND MAY NOT BE SOLD,
                  TRANSFERRED, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE
                  ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT PURSUANT TO THE
                  SECURITIES ACT OR AN OPINION OF COUNSEL REASONABLY
                  SATISFACTORY TO THE CORPORATION THAT SUCH REGISTRATION IS NOT
                  REQUIRED.

                  UNLESS PERMITTED UNDER SECURITIES LEGISLATION, THE HOLDER OF
                  THIS SECURITY MUST NOT TRADE THIS SECURITY BEFORE MARCH 4,
                  2005."

The Corporation will pay all expenses and other charges payable in connection
with the preparation, issuance and delivery of the share certificates issuable
upon the exercise of the Warrants.

5.    EXERCISE IN WHOLE OR IN PART

The Warrants may be exercised in whole or in part, and if exercised in part, the
Corporation shall issue another certificate, in a form substantially evidencing
the remaining rights to purchase Common Shares, provided that any such right
shall terminate on the Expiry Date.

This Warrant Certificate is also exchangeable from time to time, upon surrender
hereof by the Holder, for new Warrant Certificates of like tenor representing,
in the aggregate, the same number of Warrants and/or the Warrant Certificate so
surrendered.

6.    NO RIGHTS OF SHAREHOLDER UNTIL EXERCISE

The Holder shall have no rights whatsoever as a shareholder pursuant to the
Warrants (including any right to receive dividends or other distribution to
shareholders or to vote at a general meeting of the shareholders of the
Corporation), other than in respect of Common Shares in respect of which the
Holder shall have exercised its right to purchase hereunder and which the Holder
shall have actually taken up and paid for.

7.    TRANSFERABILITY

The Warrants and all rights granted hereunder may be transferred on notice to
the Corporation and in accordance with applicable securities laws. The Holder
may at any time prior to the Expiry Date, upon surrender hereof to the
Corporation at its principal office, and upon payment of the


                                     (iii)

reasonable charges of the Corporation, exchange this Warrant certificate for
other Warrant certificates evidencing Warrants entitling the Holder and/or its
transferee to acquire in the aggregate the same number of Common Shares as may
be acquired under the Warrants.

8.    FRACTIONAL COMMON SHARES

To the extent that the Holder would otherwise have been entitled to receive, on
the exercise or deemed exercise of Warrants, 0.5 or more of a Common Share, the
Holder shall be entitled to receive one Common Share. Except as provided in the
preceding sentence, no fractional Common Shares shall be issued.

9.    NO OBLIGATION TO PURCHASE

Nothing contained herein or done pursuant hereto shall obligate the Holder to
purchase or pay for, or the Corporation to issue, any Common Shares except those
Common Shares in respect of which the Holder shall have exercised its rights to
purchase in the manner provided hereunder.

10.   COVENANTS

The Corporation covenants that so long as any Warrants evidenced hereby remain
outstanding, it shall:

      10.1 reserve and there shall remain unissued out of its authorized capital
      a sufficient number of Common Shares to satisfy the right of purchase
      provided for herein should the Holder determine to exercise its rights in
      respect of all the Common Shares available for purchase and issuance under
      outstanding Warrants, and all Common Shares which shall be issued upon the
      exercise of the right to purchase provided for herein, upon payment
      therefor of the amount at which such Common Shares may at the time be
      purchased pursuant to the provisions hereof, shall be issued as fully paid
      and non-assessable Common Shares;

      10.2 make all requisite filings under the securities legislation
      applicable to it in order that the Corporation continue as a reporting
      issuer in the Province of Ontario;

      10.3 at all times maintain its existence, subject to the express
      provisions hereof;

      10.4 use its best efforts to arrange for the additional listing and
      reservation for issuance of those Common Shares issued in connection with
      the exercise of the Warrants, and ensure that its Common Shares remain
      listed and posted for trading on the facilities of the Toronto Stock
      Exchange or another recognized Canadian stock exchange until at least the
      end of the one-year period following the Expiry Date; and

      10.5 use its best efforts to well and truly perform and carry out all of
      the acts or things to be done by it as provided in this Warrant
      Certificate.

11.   DILUTION

In this Section 11, the following terms have the following meanings:


                                      (iv)

      "COMMON SHARES" means the common shares in the capital of the Corporation,
      provided that if a change referred to in Sections 11.1 or 11.2 occurs in
      respect of or affecting the Common Shares, then thereafter "Common Shares"
      means the shares or other securities or property purchasable or receivable
      on the exercise of the Warrants as a result of any such change;

      "CURRENT MARKET PRICE" at any particular date means the weighted average
      trading price of the Common Shares on the Toronto Stock Exchange (or, if
      the Common Shares are not then listed and posted for trading on the
      Toronto Stock Exchange, on any other stock exchange in Canada on which the
      Common Shares are listed and posted for trading as may be selected for
      that purpose by the board of directors of the Corporation) during the
      twenty (20) consecutive trading days ending on a date not earlier than the
      fifth trading day before the particular date or, if the Common Shares are
      not listed and posted for trading on any stock exchange, the current
      market price of the Common Shares as determined by the board of directors
      of the Corporation, which determination shall be conclusive; and for the
      purposes hereof, "trading day" means a day on which the relevant stock
      exchange is open for business and the Common Shares may be traded on that
      exchange on that day;

      "DIVIDEND PAID IN THE ORDINARY COURSE" means a dividend paid on the Common
      Shares in any financial year of the Corporation, whether in

            (i)   cash,

            (ii)  securities of the Corporation, including rights, options or
                  warrants to purchase any securities or property of the
                  Corporation or other assets of the Corporation (but excluding
                  rights, options or warrants referred to in Section 11.2.2 and
                  rights, options or warrants referred to in parentheses in
                  Section 11.2.3.4), or

            (iii) property or other assets of the Corporation,

      in each case to the extent that the amount or value of such dividend
      together with the amount or value of all other such dividends theretofore
      paid in such financial year (any such securities, property or other assets
      so distributed to be valued at the fair market value of such securities,
      property or other assets, as the case may be, as determined by the board
      of directors of the Corporation, which determination shall be conclusive)
      does not exceed the greater of:

            (i)   150% of the greater of

                  (A)   the aggregate amount of dividends paid by the
                        Corporation on the Common Shares in the period of twelve
                        (12) consecutive months ended immediately prior to the
                        first day of such financial year; and

                  (B)   one-third of the aggregate amount of dividends paid by
                        the Corporation on the Common Shares in the period of
                        thirty-six (36) consecutive months ended immediately
                        prior to the first day of such financial year; or


                                      (v)

            (ii)  100% of the consolidated net income of the Corporation before
                  extraordinary items (but after dividends payable on all shares
                  ranking prior to, or on a parity with the Common Shares, with
                  respect to the payment of dividends) for the period of twelve
                  (12) consecutive months ended immediately prior to the first
                  day of such financial year, such consolidated net income,
                  extraordinary items and dividends to be as shown in the
                  audited consolidated financial statements of the Corporation
                  for such period of twelve (12) consecutive months or if there
                  are no audited consolidated financial statements for such
                  period, computed in accordance with generally accepted
                  accounting principles, consistent with those applied in the
                  preparation of the most recent audited consolidated financial
                  statements of the Corporation; and

      "EQUITY SHARES" means the Common Shares and any shares of any other class
      or series of the Corporation which may from time to time be authorized for
      issue if by their terms such shares confer on the holders thereof the
      right to participate in the distribution of assets upon the voluntary or
      involuntary liquidation, dissolution or winding-up of the Corporation
      beyond a fixed sum or a fixed sum plus accrued dividends.

      11.1  Adjustment in Rights

            11.1.1 If, at any time after the date hereof and prior to the Expiry
            Date, there is a reclassification of the outstanding Common Shares
            or change of the Common Shares into other shares or securities or
            any other capital reorganization of the Corporation or a
            consolidation, merger or amalgamation of the Corporation with or
            into any other corporation (any such event being called a "CAPITAL
            REORGANIZATION"), each Holder shall be entitled to receive and shall
            accept for the same aggregate consideration, upon the exercise of
            the Warrants at any time after the record date on which the holders
            of Common Shares are determined for the purpose of the Capital
            Reorganization (the "relevant record date"), in lieu of the number
            of Common Shares to which it was theretofore entitled upon such
            exercise, the kind and amount of shares or other securities of the
            Corporation or of the corporation resulting from the Capital
            Reorganization that the Holder would have been entitled to receive
            as a result of such Capital Reorganization if, on the relevant
            record date, it had been the holder of record of the number of
            Common Shares in respect of which the Warrants are then being
            exercised, and such shares or other securities shall be subject to
            adjustment thereafter in accordance with provisions which are the
            same, as nearly as may be possible, as those contained in this
            Section 11; provided that no such Capital Reorganization shall be
            implemented unless all necessary steps have been taken so that each
            Holder shall be entitled to receive the kind and amount of shares or
            other securities of the Corporation or of the corporation resulting
            from the Capital Reorganization as provided above.

            11.1.2 If, at any time after the date hereof and prior to the Expiry
            Date, any adjustment in the Exercise Price shall occur as a result
            of:

            11.1.2.1 an event referred to in Section 11.2.1;


                                      (vi)

            11.1.2.2 the fixing by the Corporation of a record date for an event
            referred to in Section 11.2.2; or

            11.1.2.3 the fixing by the Corporation of a record date for an event
            referred to in Section 11.2.3 if such event constitutes the issue or
            distribution to the holders of all of its outstanding Common Shares
            of (i) Equity Shares, or (ii) securities exchangeable for or
            convertible into Equity Shares at an exchange or conversion price
            per share less than the Current Market Price on such record date, or
            (iii) rights, options or warrants to acquire Equity Shares or
            securities exchangeable for or convertible into Equity Shares at an
            exercise, exchange or conversion price per share less than the
            Current Market Price on such record date;

      then the number of Common Shares purchasable upon the subsequent exercise
      of the Warrants shall be adjusted simultaneously with the adjustment to
      the Exercise Price provided in Section 11.2 by multiplying the number of
      Common Shares issuable upon the exercise of the Warrants immediately prior
      to such adjustment by a fraction which shall be the reciprocal of the
      fraction employed in the adjustment of the Exercise Price.

11.2  Adjustment in Exercise Price

      The Exercise Price shall be subject to adjustment from time to time as
follows:

      11.2.1 If, at any time after the date hereof and prior to the Expiry Date,
      the Corporation:

            11.2.1.1 subdivides its outstanding Common Shares into a greater
            number of shares,

            11.2.1.2 consolidates its outstanding Common Shares into a smaller
            number of shares, or

            11.2.1.3 issues Common Shares to the holders of all of its
            outstanding Common Shares by way of a stock dividend or other
            distribution other than a Dividend Paid in the Ordinary Course,

      (any of such events being called a "COMMON SHARE REORGANIZATION"), the
      Exercise Price shall be adjusted effective immediately after the record
      date on which the holders of Common Shares are determined for the purpose
      of the Common Share Reorganization (the "relevant record date") by
      multiplying the Exercise Price in effect immediately prior to the relevant
      record date by a fraction:

            (i)   the numerator of which shall be the number of Common Shares
                  outstanding on the relevant record date before giving effect
                  to the Common Share Reorganization; and


                                     (vii)

            (ii)  the denominator of which shall be the number of Common Shares
                  outstanding on the relevant record date after giving effect to
                  the Common Share Reorganization.

      11.2.2 If, at any time after the date hereof and prior to the Expiry Date,
      the Corporation fixes a record date for the issue of rights, options or
      warrants to the holders of all or substantially all of its outstanding
      Common Shares (the "relevant record date") under which such holders are
      entitled, during a period expiring not more than forty five (45) days
      after the relevant record date (the "RIGHTS PERIOD"), to subscribe for or
      purchase Common Shares at a price per share, or securities exchangeable
      for or convertible into Common Shares at an exchange or conversion price
      per share less than 95% of the Current Market Price on the relevant record
      date (any of such events being called a "RIGHTS OFFERING"), the Exercise
      Price shall be adjusted effective immediately after the end of the Rights
      Period by multiplying the Exercise Price in effect immediately prior to
      the end of the Rights Period by a fraction:

            (i)   the numerator of which shall be the aggregate of:

                  (A)   the number of Common Shares outstanding on the relevant
                        record date, and

                  (B)   the number determined by dividing (1) either (a) the
                        product of the number of Common Shares issued or
                        subscribed for during the Rights Period under the Rights
                        Offering and the price at which such Common Shares were
                        offered, or, as the case may be, (b) the product of the
                        exchange or conversion price of the securities
                        exchangeable for or convertible into Common Shares and
                        the number of Common Shares for or into which the
                        securities so offered pursuant to the Rights Offering
                        could have been exchanged or converted during the Rights
                        Period, by (2) the Current Market Price on the relevant
                        record date; and

            (ii)  the denominator of which shall be, in the case of Section
                  11.2.2(i)(B)(1)(a), the number of Common Shares outstanding on
                  the relevant record date plus the number of Common Shares
                  actually issued or subscribed for during the Rights Period
                  upon exercise of the rights, warrants or options under the
                  Rights Offering and, in the case of Section
                  11.2.2(i)(B)(1)(b), the number of Common Shares outstanding at
                  the relevant record date plus the number of Common Shares for
                  or into which the securities so offered pursuant to the Rights
                  Offering could have been exchanged or converted during the
                  Rights Period.

      If a Holder has exercised the Warrants during the period beginning
      immediately after the record date for a Rights Offering and ending on the
      last day of the Rights Period for that Rights Offering then, in addition
      to the Common Shares to which the


                                     (viii)

      Holder is otherwise entitled upon such exercise pursuant to this
      agreement, the Holder shall be entitled to that number of additional
      Common Shares which, when added to the number of Common Shares to which
      the Holder is entitled upon such exercise, equals the number of Common
      Shares to which the Holder would have been entitled upon exercise if the
      Holder had exercised the Warrants immediately after the end of the Rights
      Period and after giving effect to the adjustment of the Exercise Price
      provided for in this Section 11.2.2. Such additional Common Shares shall
      be deemed to have been issued to the Holder immediately following the end
      of the Rights Period.

      11.2.3 If, at any time after the date hereof and prior to the Expiry Date,
      the Corporation fixes a record date (the "relevant record date") for the
      issue or distribution to the holders of all of its outstanding Common
      Shares of:

            11.2.3.1 shares of any class in its capital,

            11.2.3.2 evidences of its indebtedness,

            11.2.3.3 assets or property, or

            11.2.3.4 rights, options or warrants to subscribe for or purchase
            any of the foregoing (other than rights, options or warrants to
            purchase Common Shares exercisable within 45 days of the date of
            issue of the rights, options or warrants at a price per share equal
            to or greater than 95% of the Current Market Price),

      and if such issue or distribution does not constitute a Common Share
      Reorganization, a Rights Offering or a Dividend Paid in the Ordinary
      Course (any of such events referred to in Sections 11.2.3.1 through
      11.2.3.4 being called a "Special Distribution"), the Exercise Price shall
      be adjusted immediately after the relevant record date by multiplying the
      Exercise Price in effect on the relevant record date by a fraction:

            (i)   the numerator of which shall be the difference obtained when
                  (a) the amount by which the aggregate fair market value of the
                  shares, rights, options, warrants, evidences of indebtedness
                  or assets or property, as the case may be, which are
                  distributed in the Special Distribution exceeds the fair
                  market value of the consideration, if any, received therefor
                  by the Corporation, is subtracted from (b) the product
                  obtained when the number of Common Shares outstanding on the
                  relevant record date is multiplied by the Current Market Price
                  on the relevant record date; and

            (ii)  the denominator of which shall be the product obtained when
                  the number of Common Shares outstanding on the relevant record
                  date is multiplied by the Current Market Price on the relevant
                  record date;

      provided that no such adjustment shall be made if the result of such
      adjustment


                                      (ix)

      would be to increase the Exercise Price in effect immediately before the
      relevant record date. Any determination of fair market value shall be made
      by the board of directors of the Corporation and their determination shall
      be conclusive. To the extent that any Special Distribution is not made,
      the Exercise Price shall be readjusted effective immediately to the
      Exercise Price that would then be in effect based upon the shares, rights,
      options or warrants, evidences of indebtedness, assets or property
      actually distributed.

11.3  Rules for Adjustment in Rights and Exercise Price

For the purpose of this Section 11:

      11.3.1 The adjustments provided for in this Section are cumulative and
      shall be made successively wherever an event referred to in a particular
      paragraph of this Section occurs, subject to the following provisions of
      this Section.

      11.3.2 No adjustment in the Exercise Price shall be required unless such
      adjustment would require an increase or decrease of at least 1% in the
      Exercise Price and no adjustment shall be made in the number of Common
      Shares issuable on exercise of the Warrants unless it would result in a
      change of at least one-hundredths of a Common Share; provided, however,
      that any adjustments which, by reason of this Section, are not required to
      be made shall be carried forward and taken into account in a subsequent
      adjustment and so on.

      11.3.3 Any Common Shares owned by or held for the account of the
      Corporation shall be deemed not to be outstanding for the purpose of any
      computation under Section 11.2.

      11.3.4 No adjustment to the Exercise Price shall be made in respect of any
      event described in Section 11.2 (other than the events referred to in
      Sections 11.2.1.1 and 11.2.1.2) if the Holder is entitled to participate
      in such event on the same terms as though, and to the same effect as if,
      it had exercised the Warrants in full prior to or on the effective date or
      record date of such event, provided that such participation is subject to
      all necessary regulatory approval.

      11.3.5 In any case in which this Section 11 requires that an adjustment
      become effective immediately after a record date for an event referred to
      herein, the Corporation may defer, until the occurrence of such event,
      issuing to each Holder in respect of the exercise of the Warrants after
      such record date and before the occurrence of such event the additional
      Common Shares issuable upon such exercise by reason of the adjustment
      required by such event and delivering to the Holder any distributions
      declared with respect to such additional Common Shares after such record
      date and before such event; provided, however, that the Corporation
      delivers to the Holder an appropriate instrument evidencing its right to
      receive such additional Common Shares and such distributions upon the
      occurrence of the event requiring such adjustment.


                                      (x)

      11.3.6 If the Corporation fixes a record date to determine the holders of
      Common Shares entitled to receive any dividend or distribution or fixes a
      record date to take any other action and thereafter, but before the
      distribution to shareholders of any such dividend or distribution or the
      taking of such other action, the Corporation legally abandons its plan to
      pay such dividend or distribution or take such other action, then no
      adjustment pursuant to this Section shall be required by reason of the
      fixing of such record date.

      11.3.7 If the board of directors of the Corporation does not fix a record
      date for a Common Share Reorganization, Special Distribution or Rights
      Offering, the Corporation shall be deemed to have fixed as the record date
      therefor the close of business on the day on which the board of directors
      authorizes the making of the Common Shares Reorganization, Special
      Distribution or Rights Offering, as the case may be.

      11.3.8 If any question at any time arises with respect to the Exercise
      Price or the number of Common Shares issuable upon the exercise of the
      Warrants, such question shall be conclusively determined by the auditors
      from time to time of the Corporation, or if they are unable or unwilling
      to act, by such other firm of independent chartered accountants as may be
      selected by the Corporation with the concurrence of each Holder, and any
      such determination shall be binding upon each Holder, the Corporation and
      all shareholders. If any such determination is made, the Corporation shall
      deliver a certificate to each Holder describing such determination.

      11.3.9 As a condition precedent to the taking of any action which would
      require any adjustment to the Warrants represented by this Warrant
      Certificate, including the Exercise Price, the Corporation must have taken
      all action which may be necessary in order that the Corporation shall have
      issued and reserved in its authorized capital and may validly and legally
      issue as fully-paid and non-assessable all of the Common Shares or other
      securities which each Holder is entitled to receive on the full exercise
      thereof in accordance with the provisions hereof.

      11.3.10 In the case the Corporation, after date of issuance of the
      Warrants represented by this Warrant Certificate, takes any action
      affecting the Common Shares, other than an action described in this
      Section 11, which in the opinion of the directors of the Corporation would
      materially affect the rights of the Holders, the Exercise Price will be
      adjusted in such manner, if any, and at such time by action by the
      directors of the Corporation but subject in all cases to any necessary
      regulatory approval. Failure of the taking of action by the directors of
      the Corporation so as to provide for an adjustment on or prior to the
      effective date of any action by the Corporation affecting the Common
      Shares will be conclusive evidence that the directors have determined it
      to be equitable to make no adjustment.

11.4  Notice of Adjustment in Exercise Price and Rights

      11.4.1 At least fourteen (14) days prior to the effective date or record
      date, as the case may be, of any event which requires or might require an
      adjustment pursuant to this Section 11, the Corporation shall deliver to
      each Holder a certificate of the


                                      (xi)

      Corporation specifying the particulars of such event and, if determinable,
      the required adjustment and the computation of such adjustment.

      11.4.2 In case any adjustment for which a notice in Section 11.4.1 has
      been given is not then determinable, the Corporation shall promptly after
      such adjustment is determinable deliver to each Holder a certificate of
      the Corporation containing a computation of such adjustment.

12.   CONSOLIDATION AND MERGER

      12.1 The Corporation shall not enter into any transaction whereby all or
      substantially all of its undertaking, property and assets would become the
      property of any other company, corporation or other entity (herein called
      a "successor entity") whether by way of reorganization, reconstruction,
      consolidation, merger, transfer, sale, disposition or otherwise, unless
      prior to or contemporaneously with the consummation of such transaction
      the Corporation and the successor entity shall have executed such
      instruments and done such things as, in the opinion of counsel to the
      Corporation, are necessary or advisable to establish that upon the
      consummation of such transaction,:

            12.1.1 the successor entity will have assumed all the covenants and
            obligations of the Corporation under this Warrant Certificate, and

            12.1.2 this Warrant will be a valid and binding obligation of the
            successor entity entitling each Holder, as against the successor
            entity, to all the rights of the Holder under this Warrant
            Certificate.

      12.2 Whenever the conditions of Section 12.1 shall have been duly observed
      and performed, the successor entity shall possess and from time to time
      may exercise each and every right and power of the Corporation under this
      Warrant Certificate in the name of the Corporation or otherwise and any
      act or proceeding by any provision hereof required to be done or performed
      by any employee or officer of the Corporation may be done and performed
      with like force and effect by the like employees or officers of the
      successor entity.

13.   REPRESENTATION AND WARRANTY

The Corporation hereby represents and warrants to each Holder that the
Corporation is duly authorized and has the lawful power and authority to create
and issue the Warrants represented by this Warrant Certificate and the Common
Shares issuable upon the exercise of the Warrants represented by this Warrant
Certificate and perform its obligations hereunder and that this Warrant
represents a valid, legal and binding obligation of the Corporation enforceable
in accordance with its terms.

14.   TRANSFER RESTRICTION ON COMMON SHARES

If at the time of the exercise of the Warrants, there exist trading restrictions
on the Common Shares acquired due to applicable securities legislation, the
Corporation may, on the advice of counsel, endorse the Common Shares to such
effect.


                                     (xii)

15.   MISCELLANEOUS

If the certificate representing the Warrants is lost, mutilated, destroyed or
stolen, the Corporation may, on such reasonable terms as to cost and indemnity
or otherwise as it may impose, issue a replacement certificate similar as to
denomination, tenor and date as the certificate representing the Warrant so
lost, mutilated, destroyed or stolen.

Anything in this Warrant certificate to the contrary notwithstanding, the
Warrants may be exercised, and are exercisable, only to the extent permitted by
applicable law.

16.   NOTICE

Any notice, communication, payment or demand required or permitted to be given
under this Warrant shall be deemed to have been sufficiently given to the
recipient if delivered personally, or (other than in the case of payment) if
sent by facsimile or sent by ordinary first class mail within Canada, postage
prepaid, addressed as follows:

      (a)   to the Corporation at:

      Four Seasons Place
      Suite 501
      Toronto ON M9B 6H7
      Attention: Michael Byrne, Chief Financial Officer and Corporate Secretary

      Facsimile: (416) 335-9306

      (b)   to the Holder:

      78 The Bridle Path
      Toronto, Ontario
      M3B 2B1
      Attention: Leslie Dan

      Facsimile: (416) 291-2162

Any such mailing shall be deemed to be received on the date of delivery if
delivered personally, on the next business day following the transmission by
facsimile confirmed by the sender thereof or on the third business day following
the date of mailing or, in the event of any disruption, strike or interruption
in the Canadian postal service after mailing and prior to receipt, on the third
business day following full resumption of such Canadian postal service. Either
party hereto may change its facsimile number or address for the purpose of this
Section by giving written notice of such change to the other.

17.   GOVERNING LAW

The Warrants shall be governed by the laws of the Province of Ontario.

Time shall be of the essence.


                                     (xiii)

IN WITNESS WHEREOF the Corporation has authorized this certificate to be signed
by the signature of its duly authorized officer this    day of        , 200_.

                                       VIVENTIA BIOTECH INC.

                                       By: _____________________________________
                                           Name:  Michael Byrne
                                           Title: Chief Financial Officer and
                                                  Corporate Secretary



                                 SUBSCRIPTION

TO:   VIVENTIA BIOTECH INC.
      10 FOUR SEASONS PLACE
      SUITE 501
      TORONTO ON M9B 6H7
      CANADA

      The undersigned holder of the within Warrant hereby subscribes for  _____
Common Shares of Viventia Biotech Inc. (or such number of Common Shares or other
securities to which such subscription entitles it in lieu thereof or in addition
thereto under the provisions of the Warrants) at the subscription price of $2.00
for each one (1) Warrant evidenced by and on the terms specified in the Warrants
and encloses herewith a certified cheque or bank draft payable to the order of
Viventia Biotech Inc. in payment of the subscription price.

      The undersigned hereby directs that the said Common Shares be registered
as follows:



          NAME                      ADDRESS            NUMBER OF COMMON SHARES
                                                
________________________    _______________________   _________________________

                            _______________________

SIN #___________________    _______________________


(Please print full name in which share certificates are to be issued.)

DATED this ___________________ day of _____________________, 200__.

                                             _________________________________

                                             By:___________________________
                                                LESLIE L. DAN