Ex-4.3 Form of Warrant

EXHIBIT 4.3

NEITHER THESE SECURITIES NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND, ACCORDINGLY, MAY BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS. NOTWITHSTANDING THE FOREGOING, THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OR OTHER LOAN OR FINANCING ARRANGEMENT SECURED BY SUCH SECURITIES.

INTROGEN THERAPEUTICS, INC.

WARRANT

     Introgen Therapeutics, Inc., a Delaware corporation (the “Company”), hereby certifies that, for value received, [        ] or its registered assigns (the “Holder”), is entitled to purchase from the Company up to a total of [        ] shares of common stock, $0.001 par value per share (the “Common Stock”), of the Company (each such share, a “Warrant Share” and all such shares, the “Warrant Shares”) at an exercise price equal to $7.89 per share (as adjusted from time to time as provided in Section 8, the “Exercise Price”), at any time and from time to time from and after the date hereof and through and including June 18, 2008 (the “Expiration Date”), and subject to the following terms and conditions. This Warrant (this “Warrant”) is one of a series of similar warrants issued pursuant to that certain Securities Purchase Agreement dated as of the date hereof, by and among the Company and the Purchasers identified therein (the “Purchase Agreement”). All such warrants are referred to herein, collectively, as the “Warrants.”

     1.     Definitions. In addition to the terms defined elsewhere in this Warrant, capitalized terms that are not otherwise defined herein have the meanings given to such terms in the Purchase Agreement.

     2.     Registration of Warrant. The Company shall register this Warrant, upon records to be maintained by the Company for that purpose (the “Warrant Register”), in the name of the record Holder hereof from time to time. The Company may deem and treat the registered Holder of this Warrant as the absolute owner hereof for the purpose of any exercise hereof or any distribution to the Holder, and for all other purposes, absent actual notice to the contrary.

     3.     Registration of Transfers. The Company shall register the transfer of any portion of this Warrant in the Warrant Register, upon surrender of this Warrant, with the Form of Assignment

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attached hereto duly completed and signed, to the Transfer Agent or to the Company at its address specified herein. Upon any such registration or transfer, a new warrant to purchase Common Stock, in substantially the form of this Warrant (any such new warrant, a “New Warrant”), evidencing the portion of this Warrant so transferred shall be issued to the transferee and a New Warrant evidencing the remaining portion of this Warrant not so transferred, if any, shall be issued to the transferring Holder. The acceptance of the New Warrant by the transferee thereof shall be deemed the acceptance by such transferee of all of the rights and obligations of a holder of a Warrant.

     4.          Exercise and Duration of Warrants.

          (a)     This Warrant shall be exercisable by the registered Holder at any time and from time to time on or after the date hereof to and including the Expiration Date. At 6:30 P.M., New York City time, on the Expiration Date, the portion of this Warrant not exercised prior thereto shall be and become void and of no value.

          (b)     A Holder may exercise this Warrant by delivering to the Company (i) an Exercise Notice, in the form attached hereto, appropriately completed and duly signed, and (ii) payment of the Exercise Price for the number of Warrant Shares as to which this Warrant is being exercised (which may take the form of a “cashless exercise” if so indicated in the Exercise Notice), and the date such items are delivered to the Company (as determined in accordance with the notice provisions hereof) is an “Exercise Date.” Execution and delivery of the Exercise Notice shall have the same effect as cancellation of the original Warrant and issuance of a New Warrant evidencing the right to purchase the remaining number of Warrant Shares.

     5.          Delivery of Warrant Shares.

          (a)     Upon exercise of this Warrant and surrender of the original Warrant at the offices of the Company, the Company shall promptly (but in no event later than three Trading Days after the Exercise Date) issue or cause to be issued and cause to be delivered to or upon the written order of the Holder and in such name or names as the Holder may designate, a certificate for the Warrant Shares issuable upon such exercise, free of restrictive legends unless a registration statement covering the resale of the Warrant Shares and naming the Holder as a selling stockholder thereunder is not then effective and the Warrant Shares are not freely transferable without volume restrictions pursuant to Rule 144 under the Securities Act. The Holder, or any Person so designated by the Holder to receive Warrant Shares, shall be deemed to have become holder of record of such Warrant Shares as of the Exercise Date. The Company shall, upon request of the Holder, use its best efforts to deliver Warrant Shares hereunder electronically through the Depository Trust Corporation or another established clearing corporation performing similar functions.

          (b)     This Warrant is exercisable, either in its entirety or, from time to time, for a portion of the number of Warrant Shares. Upon surrender of this Warrant following one or more partial exercises, the Company shall issue or cause to be issued, at its expense, a New Warrant evidencing the right to purchase the remaining number of Warrant Shares.

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          (c)     In addition to any other rights available to a Holder, if the Company fails to deliver to the Holder a certificate representing Warrant Shares, or to deliver the Warrant shares electronically as contemplated by Section 5(a) above, if requested by the Holder, by the third Trading Day after the date on which delivery of such certificate is required by this Warrant, and if after such third Trading Day the Holder purchases (in an open market transaction or otherwise) shares of Common Stock to deliver in satisfaction of a sale by the Holder of the Warrant Shares that the Holder anticipated receiving from the Company (a “Buy-In”), then the Company shall, within three Trading Days after the Holder’s request and in the Holder’s discretion, either (i) pay cash to the Holder in an amount equal to the Holder’s total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased (the “Buy-In Price”), at which point the Company’s obligation to deliver such certificate (and to issue such Common Stock) shall terminate, or (ii) promptly honor its obligation to deliver to the Holder a certificate or certificates representing such Common Stock and pay cash to the Holder in an amount equal to the excess (if any) of the Buy-In Price over the product of (A) such number of shares of Common Stock, times (B) the Closing Price on the date of the event giving rise to the Company’s obligation to deliver such certificate.

          (d)     The Company’s obligations to issue and deliver Warrant Shares in accordance with the terms hereof are absolute and unconditional, irrespective of any action or inaction by the Holder to enforce the same, any waiver or consent with respect to any provision hereof, the recovery of any judgment against any Person or any action to enforce the same, or any setoff, counterclaim, recoupment, limitation or termination, or any breach or alleged breach by the Holder or any other Person of any obligation to the Company or any violation or alleged violation of law by the Holder or any other Person, and irrespective of any other circumstance which might otherwise limit such obligation of the Company to the Holder in connection with the issuance of Warrant Shares. Nothing herein shall limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation, a decree of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver certificates representing shares of Common Stock upon exercise of the Warrant as required pursuant to the terms hereof.

     6.     Charges, Taxes and Expenses. Issuance of certificates for shares of Common Stock upon exercise of this Warrant shall be made without charge to the Holder for any issue or transfer tax, withholding tax, transfer agent fee or other incidental tax or expense in respect of the issuance of such certificates, all of which taxes and expenses shall be paid by the Company; provided, however, that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the registration of any certificates for Warrant Shares or Warrants in a name other than that of the Holder or an Affiliate thereof. The Holder shall be responsible for all other tax liability that may arise as a result of holding or transferring this Warrant or receiving Warrant Shares upon exercise hereof.

     7.     Reservation of Warrant Shares. The Company covenants that it will at all times reserve and keep available out of the aggregate of its authorized but unissued and otherwise unreserved Common Stock, solely for the purpose of enabling it to issue Warrant Shares upon exercise of this Warrant as herein provided, the number of Warrant Shares which are then issuable and deliverable upon the exercise of this entire Warrant, free from preemptive rights or any other contingent purchase rights of persons other than the Holder (taking into account the adjustments and

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restrictions of Section 8). The Company covenants that all Warrant Shares so issuable and deliverable shall, upon issuance and the payment of the applicable Exercise Price in accordance with the terms hereof, be duly and validly authorized, issued and fully paid and nonassessable. The Company will take all such action as may be necessary to assure that such shares of Common Stock may be issued as provided herein without violation of any applicable law or regulation or of any requirements of any securities exchange or automated quotation system upon which the Common Stock may be listed.

     8.     Certain Adjustments. The Exercise Price and number of Warrant Shares issuable upon exercise of this Warrant are subject to adjustment from time to time as set forth in this Section 8.

          (a)     Stock Dividends and Splits. If the Company, at any time while this Warrant is outstanding, (i) pays a stock dividend on its Common Stock or otherwise makes a distribution on any class of capital stock that is payable in shares of Common Stock, (ii) subdivides outstanding shares of Common Stock into a larger number of shares, or (iii) combines outstanding shares of Common Stock into a smaller number of shares, then in each such case the Exercise Price shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock outstanding immediately before such event and of which the denominator shall be the number of shares of Common Stock outstanding immediately after such event. Any adjustment made pursuant to clause (i) of this paragraph shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend or distribution, and any adjustment pursuant to clause (ii) or (iii) of this paragraph shall become effective immediately after the effective date of such subdivision or combination.

          (b)     Pro Rata Distributions. If the Company, at any time while this Warrant is outstanding, distributes to holders of Common Stock (i) evidences of its indebtedness, (ii) any security (other than a distribution of Common Stock covered by the preceding paragraph), (iii) rights or warrants to subscribe for or purchase any security, or (iv) any other asset, including cash (in each case, “Distributed Property”), then in each such case the Exercise Price in effect immediately prior to the record date fixed for determination of stockholders entitled to receive such distribution shall be adjusted (effective on such record date) to equal the product of such Exercise Price times a fraction of which the denominator shall be the average of the Closing Prices for the five Trading Days immediately prior to (but not including) such record date and of which the numerator shall be such average less the then fair market value of the Distributed Property distributed in respect of one outstanding share of Common Stock, as determined (except in the case of cash) by the Company’s independent certified public accountants that regularly examine the financial statements of the Company (an “Appraiser”). In such event, the Holder, after receipt of the determination by the Appraiser, shall have the right to select an additional appraiser (which shall be a nationally recognized accounting firm), in which case such fair market value shall be deemed to equal the average of the values determined by each of the Appraiser and such appraiser.

          (c)     Fundamental Transactions. If, at any time while this Warrant is outstanding, (i) the Company effects any merger or consolidation of the Company with or into another Person, (ii) the Company effects any sale of all or substantially all of its assets in one or a series of related

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transactions, (iii) any tender offer or exchange offer (whether by the Company or another Person) is completed pursuant to which holders of Common Stock are permitted to tender or exchange their shares for other securities, cash or property, or (iv) the Company effects any reclassification of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is effectively converted into or exchanged for other securities, cash or property (in any such case, a “Fundamental Transaction”), then (x) if the consideration to be received in such Fundamental Transaction does not include any equity securities, then the Warrant shall terminate immediately prior to the effectiveness of such Fundamental Transaction or (y) if the consideration to be received in such Fundamental Transaction does include equity securities (an “Equity Security Fundamental Transaction”), then the Holder shall have the right thereafter to receive, upon exercise of this Warrant, the same amount and kind of securities, cash or property as it would have been entitled to receive upon the occurrence of such Equity Security Fundamental Transaction if it had been, immediately prior to such Equity Security Fundamental Transaction, the holder of the number of Warrant Shares then issuable upon exercise in full of this Warrant (the “Alternate Consideration”). The aggregate Exercise Price for this Warrant will not be affected by any such Equity Security Fundamental Transaction, but the Company shall apportion such aggregate Exercise Price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received in an Equity Security Fundamental Transaction, then the Holder shall be given the same choice as to the Alternate Consideration it receives upon any exercise of this Warrant following such Equity Security Fundamental Transaction. At the Holder’s request, any successor to the Company or surviving entity in such Equity Security Fundamental Transaction shall issue to the Holder a new warrant consistent with the foregoing provisions and evidencing the Holder’s right to purchase the Alternate Consideration for the aggregate Exercise Price upon exercise thereof. The terms of any agreement pursuant to which an Equity Security Fundamental Transaction is effected shall include terms requiring any such successor or surviving entity to comply with the provisions of this paragraph (c) and insuring that the Warrant (or any such replacement security) will be similarly adjusted upon any subsequent transaction analogous to an Equity Security Fundamental Transaction. If any Equity Security Fundamental Transaction constitutes or results in a Change of Control, then at the request of the Holder delivered before the 90th day after such Equity Security Fundamental Transaction, the Company (or any such successor or surviving entity) will purchase the Warrant from the Holder for a purchase price, payable in cash within five Trading Days after such request (or, if later, on the effective date of the Equity Security Fundamental Transaction), equal to the Black Scholes value of the remaining unexercised portion of this Warrant on the date of such request. “Change of Control” means the occurrence of any of the following in one or a series of related transactions: (i) an acquisition after the date hereof by an individual or legal entity or “group” (as described in Rule 13d-5(b)(1) under the Exchange Act) of more than one-third of the voting rights or equity interests in the Company; (ii) a replacement of more than one-half of the members of the Company’s board of directors that is not approved by those individuals who are members of the board of directors on the date hereof (or other directors previously approved by such individuals); (iii) a merger or consolidation of the Company or any Subsidiary or a sale of more than one-third of the assets of the Company in one or a series of related transactions, unless following such transaction or series of transactions, the holders of the Company’s securities prior to the first such transaction continue to hold at least two-thirds of the voting rights and equity interests in of the surviving entity or acquirer of such assets; (iv) a recapitalization,

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reorganization or other transaction involving the Company or any Subsidiary that constitutes or results in a transfer of more than one-third of the voting rights or equity interests in the Company; (v) consummation of a “Rule 13e-3 transaction” as defined in Rule 13e-3 under the Exchange Act with respect to the Company; or (vi) the execution by the Company or its controlling stockholders of an agreement providing for or reasonably likely to result in any of the foregoing events.

          (d)     Subsequent Equity Sales.

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          (e)     Number of Warrant Shares. Simultaneously with any adjustment to the Exercise Price pursuant to paragraphs (a), (b) or (d) of this Section, the number of Warrant Shares that may be purchased upon exercise of this Warrant shall be increased or decreased proportionately, so that after such adjustment the aggregate Exercise Price payable hereunder for the increased or decreased number of Warrant Shares shall be the same as the aggregate Exercise Price in effect immediately prior to such adjustment.

          (f)     Calculations. All calculations under this Section 8 shall be made to the nearest cent or the nearest 1/100th of a share, as applicable. The number of shares of Common Stock outstanding at any given time shall not include shares owned or held by or for the account of the Company, and the disposition of any such shares shall be considered an issue or sale of Common Stock.

          (g)     Notice of Adjustments. Upon the occurrence of each adjustment pursuant to this Section 8, the Company at its expense will promptly compute such adjustment in accordance with the terms of this Warrant and prepare a certificate setting forth such adjustment, including a statement of the adjusted Exercise Price and adjusted number or type of Warrant Shares or other securities, cash or property issuable upon exercise of this Warrant (as applicable), describing the transactions giving rise to such adjustments and showing in detail the facts upon which such adjustment is based. Upon written request, the Company will promptly deliver a copy of each such certificate to the Holder and to the Company’s Transfer Agent.

          (h)     Notice of Corporate Events. If the Company (i) declares a dividend or any other distribution of cash, securities or other property in respect of its Common Stock, including without limitation any granting of rights or warrants to subscribe for or purchase any capital stock of the Company or any Subsidiary, (ii) authorizes or approves, enters into any agreement contemplating or solicits stockholder approval for any Fundamental Transaction or (iii) authorizes the voluntary dissolution, liquidation or winding up of the affairs of the Company, then the Company shall deliver to the Holder a notice describing the material terms and conditions of such transaction, at least 20 calendar days prior to the applicable record or effective date on which a Person would need to hold Common Stock in order to participate in or vote with respect to such transaction, and the Company will take all steps reasonably necessary in order to insure that the Holder is given the practical opportunity to exercise this Warrant prior to such time so as to participate in or vote with respect to such transaction; provided, however, that the failure to deliver such notice or any defect therein shall not affect the validity of the corporate action required to be described in such notice.

     9.          Payment of Exercise Price. The Holder shall pay the Exercise Price in one of the following manners:

          (a)     Cash Exercise. The Holder may deliver immediately available funds; or

          (b)     Cashless Exercise. The Holder may satisfy its obligation to pay the Exercise Price through a “cashless exercise,” in which event the Company shall issue to the Holder the number of Warrant Shares determined as follows:

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For purposes of Rule 144 promulgated under the Securities Act, it is intended, understood and acknowledged that the Warrant Shares issued in a cashless exercise transaction shall be deemed to have been acquired by the Holder, and the holding period for the Warrant Shares shall be deemed to have commenced, on the date this Warrant was originally issued pursuant to the Purchase Agreement.

     10.          Limitation on Exercise.

          (a)     Notwithstanding anything to the contrary contained herein, the number of shares of Common Stock that may be acquired by the Holder upon any exercise of this Warrant (or otherwise in respect hereof) shall be limited to the extent necessary to insure that, following such exercise (or other issuance), the total number of shares of Common Stock then beneficially owned by such Holder and its Affiliates and any other Persons whose beneficial ownership of Common Stock would be aggregated with the Holder’s for purposes of Section 13(d) of the Exchange Act does not exceed 9.999% (the “Maximum Percentage”) of the total number of issued and outstanding shares of Common Stock (including for such purpose the shares of Common Stock issuable upon such exercise). For such purposes, beneficial ownership shall be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. Each delivery of an Exercise Notice hereunder will constitute a representation by the Holder that it has evaluated the limitation set forth in this paragraph and determined that issuance of the full number of Warrant Shares requested in such Exercise Notice is permitted under this paragraph. The Company’s obligation to issue shares of Common Stock in excess of the limitation referred to in this Section shall be suspended (and shall not terminate or expire notwithstanding any contrary provisions hereof) until such time, if any, as such shares of Common Stock may be issued in compliance with such limitation. By written notice to the Company, the Holder may waive the provisions of this Section or increase or decrease the Maximum Percentage to any other percentage specified in such notice, but (i) any such waiver or increase or decrease will not be effective until the 61st day after such notice is delivered to the Company, and (ii) any such waiver or increase or decrease will apply only to the Holder and not to any other holder of Warrants.

          (b)     Notwithstanding anything to the contrary contained herein, if the Trading Market is the New York Stock Exchange, the Nasdaq National Market or any other market or

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exchange with similar applicable rules, then the maximum number of shares of Common Stock that the Company may issue pursuant to the Transaction Documents at an effective purchase price less than the Closing Price on the Trading Day immediately preceding the Closing Date equals 4,319,900 shares (the “Issuable Maximum”), unless the Company obtains the Stockholder Approval. If, at the time any Purchaser requests an exercise of any of the Warrants, the Actual Minimum (excluding any shares issued or issuable at an effective purchase price in excess of the Closing Price on the Trading Day immediately preceding the Closing Date) exceeds the Issuable Maximum and if the Company has not previously obtained the Stockholder Approval, then the Company shall issue to the Purchaser requesting such exercise a number of shares of Common Stock not exceeding such Purchaser’s pro-rata portion of the Issuable Maximum (based on such Purchaser’s share (vis-à-vis other Purchasers) of the aggregate purchase price paid under the Purchase Agreement and taking into account any Shares and Warrant Shares previously issued to such Purchaser), and the remainder of the Warrant Shares issuable in connection with such exercise or conversion (if any) shall constitute “Excess Shares” pursuant to Section 10(c) below. For the purposes hereof, “Actual Minimum” shall mean, as of any date, the maximum aggregate number of shares of Common Stock then issued or potentially issuable in the future pursuant to the Transaction Documents, including any Underlying Shares issuable upon exercise in full of all Warrants, ignoring any limits on the number of shares of Common Stock that may be owned by a Purchaser at any one time. For the purposes hereof, “Stockholder Approval” shall mean the vote of stockholders as may be required by the applicable rules and regulations of the Trading Market applicable to approve the issuance of shares of Common Stock in excess of the Issuable Maximum. No Shares or Warrant Shares shall be entitled to vote for purposes of the Stockholder Approval.

          (c)     In the event that any Purchaser’s receipt of shares of Common Stock upon exercise of this Warrant is restricted based on the Issuable Maximum, the Company shall either: (i) use its best efforts to obtain the Stockholder Approval as soon as is reasonably possible, but in any event not later than the 60th day after the event giving rise to such Excess Shares, or (ii) within five Trading Days after such event, pay cash to such Purchaser, as liquidated damages and not as a penalty, in an amount equal to the difference between the Black Scholes value of this Warrant assuming the limitations in Section 10(b) were not applicable and the Black Scholes value of this Warrant after giving effect to the limitations in Section 10(b), measured as of the date of such event or, if greater, the date of payment (such difference, the “Cash Amount”). If the Company elects the first option under the preceding sentence and the Company fails to obtain the Stockholder Approval on or prior to the 60th day after such event, then within three Trading Days after such 60th day, the Company shall pay the Cash Amount to such Purchaser, as liquidated damages and not as a penalty. In the event the Company fails to pay the Cash Amount in a timely manner, such payment until paid in full shall bear interest at the rate of 1.5% per month or such lesser maximum rate that is permitted to be paid by applicable law (prorated for partial months).

     11.     Fractional Shares. The Company shall not be required to issue or cause to be issued fractional Warrant Shares on the exercise of this Warrant. If any fraction of a Warrant Share would, except for the provisions of this Section, be issuable upon exercise of this Warrant, the number of Warrant Shares to be issued will be rounded up to the nearest whole share.

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     12.     Notices. Any and all notices or other communications or deliveries hereunder (including without limitation any Exercise Notice) shall be in writing and shall be deemed given and effective on the earliest of (i) the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number specified in this Section prior to 6:30 p.m. (New York City time) on a Trading Day, (ii) the next Trading Day after the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number specified in this Section on a day that is not a Trading Day or later than 6:30 p.m. (New York City time) on any Trading Day, (iii) the Trading Day following the date of mailing, if sent by nationally recognized overnight courier service, or (iv) upon actual receipt by the party to whom such notice is required to be given. The address for such notices or communications shall be as set forth in the Purchase Agreement.

     13.     Warrant Agent. The Company shall serve as warrant agent under this Warrant. Upon 30 days’ notice to the Holder, the Company may appoint a new warrant agent. Any corporation into which the Company or any new warrant agent may be merged or any corporation resulting from any consolidation to which the Company or any new warrant agent shall be a party or any corporation to which the Company or any new warrant agent transfers substantially all of its corporate trust or shareholders services business shall be a successor warrant agent under this Warrant without any further act. Any such successor warrant agent shall promptly cause notice of its succession as warrant agent to be mailed (by first class mail, postage prepaid) to the Holder at the Holder’s last address as shown on the Warrant Register.

     14.     Exercise at the Option of the Company. Subject to the limitations set forth in Section 10, at any time on or after June 18, 2005, the Company may require the Holder to exercise at the Exercise Price all of the Warrants if the average of the Closing Prices during any 20 consecutive Trading Days is greater than $15.78 (subject to adjustments for stock splits, recapitalizations and similar events). Within 10 Trading Days of any such 20 Trading Day period, the Company may elect its right to require the Holder to exercise the Warrant by delivering to the Holder a written notice of such election. The Holder shall exercise the Warrant within 10 calendar days of its receipt of the Company’s written notice.

     15.     Miscellaneous.

          (a)     This Warrant shall be binding on and inure to the benefit of the parties hereto and their respective successors and assigns. Subject to the preceding sentence, nothing in this Warrant shall be construed to give to any Person other than the Company and the Holder any legal or equitable right, remedy or cause of action under this Warrant. This Warrant may be amended only in writing signed by the Company and the Holder or their respective successors and assigns.

          (b)     The Company will not, by amendment of its governing documents or through any reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the Holder against impairment. Without limiting the generality of the foregoing, the Company (a) will not increase the par value of any Warrant Shares above the amount payable therefor on such

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exercise, (b) will take all such action as may be reasonably necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable Warrant Shares on the exercise of this Warrant, and (c) will not close its stockholder books or records in any manner which interferes with the timely exercise of this Warrant.

          (c)     Governing Law; Venue; Waiver of Jury Trial. The corporate laws of the State of Delaware shall govern all issues concerning the relative rights of the Company and its stockholders. All questions concerning the construction, validity, enforcement and interpretation of this Warrant shall be governed by and construed and enforced in accordance with the laws of the State of Texas. Each party hereby irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in the City of Dallas, for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein (including with respect to the enforcement of any of the Transaction Documents), and hereby irrevocably waives, and agrees not to assert in any suit, action or proceeding, any claim that it is not personally subject to the jurisdiction of any such court, that such suit, action or proceeding is improper. Each party hereby irrevocably waives personal service of process and consents to process being served in any such suit, action or proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence of delivery) to such party at the address in effect for notices to it under this Agreement and agrees that such service shall constitute good and sufficient service of process and notice thereof. Nothing contained herein shall be deemed to limit in any way any right to serve process in any manner permitted by law. The Company hereby waives all rights to a trial by jury.

          (d)     The headings herein are for convenience only, do not constitute a part of this Warrant and shall not be deemed to limit or affect any of the provisions hereof.

          (e)     In case any one or more of the provisions of this Warrant shall be invalid or unenforceable in any respect, the validity and enforceability of the remaining terms and provisions of this Warrant shall not in any way be affected or impaired thereby and the parties will attempt in good faith to agree upon a valid and enforceable provision which shall be a commercially reasonable substitute therefor, and upon so agreeing, shall incorporate such substitute provision in this Warrant.

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     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed by its authorized officer as of the date first indicated above.

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FORM OF EXERCISE NOTICE

(To be executed by the Holder to exercise the right to purchase shares of Common Stock under the foregoing Warrant)

To Introgen Therapeutics, Inc.

The undersigned is the Holder of Warrant No.          (the “Warrant”) issued by Introgen Therapeutics, Inc., a Delaware corporation (the “Company”). Capitalized terms used herein and not otherwise defined have the respective meanings set forth in the Warrant.

FORM OF ASSIGNMENT

     [To be completed and signed only upon transfer of Warrant]

     FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers unto                  the right represented by the within Warrant to purchase        shares of Common Stock of Introgen Therapeutics, Inc. to which the within Warrant relates and appoints                  attorney to transfer said right on the books of Introgen Therapeutics, Inc. with full power of substitution in the premises.

     Dated:          ,      

In the presence of: